Columbia Thermostat Fund NCSRS Certified semi-annual shareholder report (management investment company)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED
MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number			811-01829

Columbia Acorn Trust
(Exact name of registrant as specified in charter)

One Financial Center, Boston, Massachusetts					02111
(Address of principal executive offices)					(Zip code)

James R. Bordewick, Jr., Esq. Columbia Management Advisors, LLC One Financial Center Boston, MA 02111
(Name and address of agent for service)

Registrant’s telephone number, including area code:				1-617-426-3750

Date of fiscal year end:	December 31

Date of reporting period:		June 30, 2009

Form N-CSR is to be used by management investment companies to file reports with the Commission not later than 10 days after the transmission to stockholders of any report that is required to be transmitted to stockholders under Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1). The Commission may use the information provided on Form N-CSR in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-CSR, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-CSR unless the Form displays a currently valid Office of Management and Budget ("OMB") control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. § 3507.

Item 1. Reports to Stockholders.

Q2 2009

Columbia Management^®

Columbia Acorn Family of Funds

Class Z Shares

Managed by Columbia Wanger Asset Management, L.P.

Semiannual Report

June 30, 2009

n Columbia^SM
Acorn® Fund

n Columbia^SM
Acorn International®

n Columbia^SM
Acorn USA®

n Columbia^SM
Acorn International Select^SM

n Columbia^SM
Acorn Select^SM

n Columbia^SM
Thermostat Fund^SM

NOT FDIC INSURED

NOT BANK ISSUED

May Lose Value

No Bank Guarantee

You are invited to the 2009 Columbia Acorn Funds Shareholder Information Meeting!

When: Wednesday, September 30, 2009
12 noon to 1 p.m. Central time

Where: Chase Bank Auditorium, Plaza Level
10 South Dearborn Street
Chicago, Illinois

A buffet lunch will be served at 11:30 a.m.

If you plan to join us in Chicago, please RSVP by September 25
by calling (800) 922-6769.

The Chase Bank Auditorium is located within the Chase Tower at the corner of Madison St. and Dearborn St. After entering the building, please take the escalators down to the plaza level and follow the signs to the Chase Bank Auditorium.

View a Replay on our Website

For those who are unable to join us in Chicago, a webcast replay of the meeting will be available from October 7 through October 31, 2009, at www.columbiafunds.com. Look under "New and Noteworthy" on our home page for more information.

The views expressed in the "Squirrel Chatter II" and "In a Nutshell" commentaries reflect the current views of the respective authors. These views are not guarantees of future performance and involve certain risks, uncertainties and assumptions that are difficult to predict so actual outcomes and results may differ significantly from the views expressed. These views are subject to change at any time based upon economic, market or other conditions and the respective authors disclaim any responsibility to update such views. These views may not be relied upon as investment advice and, because investment decisions for a Columbia Acorn Fund are based on numerous factors, may not be relied upon as an indication of trading intent on behalf of any particular Columbia Acorn Fund. References to specific company securities should not be construed as a recommendation or investment advice and there can be no assurance that as of the date of publication of this report, the securities mentioned in each Fund's portfolio are still held or that the securities sold have not been repurchased.

Robert E. Nason Remembered

Robert E. Nason

On June 27, 2009, Columbia Acorn Funds Board of Trustees chairman Robert Nason passed away. Bob was a man of great personal integrity who maintained the independence of the Board and worked to promote the interests of shareholders. He joined the Acorn Funds Board in November of 1998, became vice chairman in March 2001 and was named chairman in October of 2001. He served in that capacity until his death.

Bob was the second chairman of the Columbia Acorn Trust; he succeeded Irving Harris, who was chairman from its inception in 1970. Bob had impressive credentials, having served as CEO of the accounting firm Grant Thornton where he worked for 40 years.

Bob's tenure as Trust chairman occurred during a period of change in the regulatory environment and several changes involving the Fund's advisor. Throughout, he served shareholders well and his letters to shareholders in the Funds' annual reports were thoughtful and informative.

As regulators pushed mutual fund boards toward more independence from fund advisors, Bob successfully maintained the Columbia Acorn Board's history of independence. Under Bob's tenure, the Board hired a chief compliance officer, who vigilantly pursues shareholder interests. Several safeguards against market timing were implemented, including restrictions on frequent trading and statistical fair valuation of foreign stocks.

Also during Bob's tenure, the Trust's advisor, Columbia Wanger Asset Management (CWAM), had ownership changes and retirements of founder Ralph Wanger and portfolio manager Leah Zell. Bob and the Board saw to it that CWAM stayed the course, maintaining its time-tested investment process, developing and keeping talented investment professionals, and sustaining its autonomous and creative environment.

When cash inflows approached levels that could have threatened performance, Bob and the Board acted to increase investment minimums. Under his leadership, fee breakpoints were implemented, causing shareholders to benefit from growth and economies of scale. The Board, in addition, reduced 12b-1 fees and after intensive analysis, successfully initiated securities lending.

Bob is survived by his wife Carol, son Steven (Abbie Baynes), daughter Jill and grandchildren Sara and Ben.

We are fortunate to have known Bob and we will miss him. He was a man of great vision and we will strive to build on the momentum he created and to maintain the legacies of the Columbia Acorn Trust.

Allan Muchin

Vice Chairman of the Board of Trustees
Columbia Acorn Trust

Charles McQuaid

President and Chief Investment Officer
Columbia Wanger Asset Management, L.P.

Columbia Acorn Family of Funds

Table of Contents

Performance At A Glance					1

Description of Indexes					2

Squirrel Chatter II: Agriculture's Amazing Progress					3

Understanding Your Expenses					6

Columbia Acorn Fund

In a Nutshell					8

At a Glance					9

Major Portfolio Changes					20

Statement of Investments					23

Columbia Acorn International

In a Nutshell					10

At a Glance					11

Major Portfolio Changes					35

Statement of Investments					37

Portfolio Diversification					44

Columbia Acorn USA

In a Nutshell					12

At a Glance					13

Major Portfolio Changes					45

Statement of Investments					47

Columbia Acorn International Select

In a Nutshell					14

At a Glance					15

Major Portfolio Changes					55

Statement of Investments					57

Portfolio Diversification					60

Columbia Acorn Select

In a Nutshell					16

At a Glance					17

Major Portfolio Changes					61

Statement of Investments					62

Columbia Thermostat Fund

In a Nutshell					18

At a Glance					19

Statement of Investments					66

Columbia Acorn Family of Funds

Statements of Assets and Liabilities					68

Statements of Operations					69

Statements of Changes in Net Assets					70

Financial Highlights					74

Notes to Financial Statements					77

Management Fee Evaluation of the Senior Officer					85

Board Approval of the Advisory Agreement					90

Columbia Acorn Family of Funds Information					93

2009 Mid-Year Distributions

The following table lists the mid-year per share distributions for Columbia Acorn International, Columbia Acorn International Select and Columbia Thermostat Fund. The other Columbia Acorn Funds did not have mid-year distributions. The record date was June 9, 2009. The ex-dividend date was June 10, 2009, and the payable date was June 11, 2009.

	Short-term Capital Gains	Long-term Capital Gains	Ordinary Income		Reinvestment Price
Columbia Acorn International – Class Z	None	None	$	0.5309	$	27.62
Columbia Acorn International Select – Class Z	None	None	$	0.2359	$	19.72
Columbia Thermostat Fund – Class Z	None	None	$	0.0290	$	8.99

Columbia Acorn Family of Funds

Performance At A Glance Class Z Average Annual Total Returns through 6/30/09

	NAV on 6/30/09		2nd quarter*			Year to date*			1 year			3 years			5 years			10 years			Life of Fund
Columbia Acorn Fund (ACRNX) (6/10/70)	$	19.44		20.90	%		9.77	%		-25.83	%		-7.72	%		0.95	%		7.25	%		14.25	%
Russell 2500 Index				20.27	%		6.52	%		-26.72	%		-9.31	%		-0.93	%		3.67	%		NA
S&P 500 Index				15.93	%		3.16	%		-26.21	%		-8.22	%		-2.24	%		-2.22	%		10.11	%
Lipper Small-Cap Core Index				22.23	%		8.23	%		-25.01	%		-8.74	%		-0.93	%		4.32	%		NA
Lipper Mid-Cap Growth Index				19.10	%		13.91	%		-30.39	%		-6.29	%		0.39	%		0.29	%		NA
Columbia Acorn International (ACINX) (9/23/92)	$	27.53		33.30	%		21.31	%		-28.00	%		-3.22	%		8.47	%		6.96	%		10.50	%
S&P Global Ex-U.S. Between $500 Million and $5 Billion Index				34.15	%		24.54	%		-26.45	%		-4.02	%		7.13	%		6.80	%		7.49	%
S&P Global Ex-U.S. SmallCap Index				35.88	%		24.20	%		-29.89	%		-6.09	%		5.69	%		5.95	%		6.61	%
MSCI EAFE Index				25.43	%		7.95	%		-31.35	%		-7.98	%		2.31	%		1.18	%		5.09	%
Lipper International Small/ Mid Growth Index				33.20	%		23.05	%		-32.90	%		-7.44	%		5.22	%		6.42	%		NA
Columbia Acorn USA (AUSAX) (9/4/96)	$	17.71		19.42	%		8.05	%		-28.24	%		-10.37	%		-1.81	%		4.02	%		7.79	%
Russell 2000 Index				20.69	%		2.64	%		-25.01	%		-9.89	%		-1.71	%		2.38	%		4.71	%
Russell 2500 Index				20.27	%		6.52	%		-26.72	%		-9.31	%		-0.93	%		3.67	%		6.31	%
S&P 500 Index				15.93	%		3.16	%		-26.21	%		-8.22	%		-2.24	%		-2.22	%		4.46	%
Lipper Small-Cap Growth Index				20.60	%		13.14	%		-25.73	%		-9.04	%		-2.32	%		1.16	%		3.03	%
Columbia Acorn Int'l Select (ACFFX) (11/23/98)	$	19.70		23.44	%		9.60	%		-34.62	%		-2.25	%		7.10	%		5.54	%		7.94	%
S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index				28.70	%		14.93	%		-30.16	%		-7.29	%		4.30	%		5.24	%		5.84	%
MSCI EAFE Index				25.43	%		7.95	%		-31.35	%		-7.98	%		2.31	%		1.18	%		1.87	%
Lipper International Funds Index				25.64	%		10.11	%		-30.14	%		-6.52	%		3.35	%		2.44	%		3.15	%
Columbia Acorn Select (ACTWX) (11/23/98)	$	17.50		28.11	%		24.38	%		-32.90	%		-7.81	%		0.26	%		5.31	%		7.67	%
S&P MidCap 400 Index				18.75	%		8.47	%		-28.02	%		-7.54	%		0.36	%		4.62	%		6.05	%
S&P 500 Index				15.93	%		3.16	%		-26.21	%		-8.22	%		-2.24	%		-2.22	%		-0.49	%
Lipper Mid-Cap Growth Index				19.10	%		13.91	%		-30.39	%		-6.29	%		0.39	%		0.29	%		2.96	%
Columbia Thermostat Fund (COTZX) (9/25/02)†	$	8.79		19.33	%		7.67	%		-21.62	%		-4.28	%		0.17	%		—			3.86	%
S&P 500 Index				15.93	%		3.16	%		-26.21	%		-8.22	%		-2.24	%		—			3.75	%
Barclays Capital U.S. Aggregate Bond Index				1.78	%		1.90	%		6.05	%		6.43	%		5.01	%		—			4.59	%
Barclays Capital U.S. Intermediate Credit Bond Index				7.59	%		7.53	%		4.28	%		5.05	%		4.04	%		—			4.45	%
Lipper Flexible Portfolio Funds Index				13.00	%		7.59	%		-21.04	%		-3.36	%		1.16	%		—			5.21	%
50/50 Blended Benchmark††				8.76	%		2.95	%		-10.69	%		-0.73	%		1.63	%		—			4.48	%

*Not annualized.

Performance data quoted represents past performance and current performance may be lower or higher. Past performance is no guarantee of future results. The investment return and principal value of an investment in a Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Please visit columbiafunds.com for daily and most recent month-end updates. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC). If they were included, returns would have been lower. Class Z shares are sold only at NAV with no Rule 12b-1 fee. Only eligible investors may purchase Class Z shares of the Funds, directly or by exchange. Please see each Fund's prospectus for eligibility and other details. Class Z shares have limited eligibility and the investment minimum requirement may vary.

Performance results reflect any fee waivers or reimbursements of Fund expenses by the investment advisor and/or any of its affiliates. Absent these fee waivers or expense reimbursement arrangements, performance results would have been lower.

Annual operating expense ratios are as stated in each Fund prospectus that is current as of the date of this report and differences in expense ratios disclosed elsewhere in this report may result from including fee waivers and expense reimbursements as well as different time periods used in calculating the ratios. Columbia Acorn Fund Class Z: 0.76%. Columbia Acorn International Class Z: 0.96%. Columbia Acorn USA Class Z: 1.01%. Columbia Acorn International Select Class Z: 1.21%. Columbia Acorn Select Class Z: 0.95%. Columbia Thermostat Fund has a contractual expense waiver or reimbursement that expires April 30, 2010. Expense ratios without and with the contractual waiver, including fees and expenses associated with the Fund's investments in other investment companies, for Class Z shares are 1.05% and 0.97%, respectively. Absent the waiver or reimbursement, performance results would have been lower.

†A "fund of funds" bears its allocable share of the costs and expenses of the underlying funds in which it invests. Such funds are thus subject to two levels of fees and potentially higher expense ratios than would be associated with an investment in a fund that invests and trades directly in financial instruments under the direction of a single manager.

††The 50/50 Blended Benchmark is a custom supplemental benchmark established by the advisor.

All results shown assume reinvestment of distributions and do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption of fund shares.

Unlike mutual funds, indexes are not actively managed and do not incur fees or expenses. It is not possible to invest directly in an index. For index definitions, see Page 2.

The dates in parentheses are the inception dates for each respective Fund.

Columbia Acorn Family of Funds

Descriptions of Indexes Included in this Report

• 50/50 Blended Benchmark, established by the Fund's advisor, is an equally weighted custom composite of Columbia Thermostat Fund's primary equity and primary debt benchmarks, the S&P 500 Index and the Barclays Capital U.S. Aggregate Bond Index, respectively. The percentage of the Fund's assets allocated to underlying stock and bond portfolio funds will vary, and accordingly the composition of the Fund's portfolio will not always reflect the composition of the 50/50 Blended Benchmark.

• Barclays Capital U.S. Aggregate Bond Index is a market value-weighted index that tracks the daily price, coupon, pay-downs and total return performance of fixed-rate, publicly placed, dollar-denominated and non-convertible investment grade debt issues with at least $250 million par amount outstanding and with at least one year to final maturity.

• Barclays Capital U.S. Intermediate Credit Bond Index is the intermediate component of the Barclay's Capital U.S. Credit Index. The Barclay's Capital U.S. Credit Index includes publicly issued U.S. corporate and foreign debentures and secured notes that meet specified maturity, liquidity and quality requirements.

• Lipper Indexes include the largest funds tracked by Lipper, Inc. in the named category. Lipper Small-Cap Core Funds Index, 30 largest small-cap core funds; Lipper Mid-Cap Growth Index, 30 largest mid-cap growth funds; Lipper International Small/Mid Growth Index, 10 largest non-U.S. small/mid growth funds, including Col umbia Acorn International; Lipper Small-Cap Growth Index, 30 largest small-cap growth funds; Lipper International Funds Index, 30 largest non-U.S. funds, excluding non-U.S. small-cap funds; Lipper Flexible Portfolio Funds Index, an equal-weighted index of the 30 largest mutual funds within the Flexible Portfolio fund classification, as defined by Lipper.

• Morgan Stanley Capital International Europe, Australasia, Far East (MSCI EAFE) Index is a capitalization-weighted index that tracks the total return of common stocks in 21 developed-market countries within Europe, Australasia and the Far East.

• Russell 2000 Index measures the performance of the 2,000 smallest companies in the Russell 3000 Index, which represents approximately 8% of the total market capitalization of the Russell 3000 Index.

• Russell 2500 Index measures the performance of the 2,500 smallest companies in the Russell 3000 Index, which represents approximately 17% of the total market capitalization of the Russell 3000 Index.

• Standard & Poor's (S&P) 500 Index tracks the performance of 500 widely held, large-capitalization U.S. stocks.

• Standard & Poor's (S&P) MidCap 400 Index is a market value-weighted index that tracks the performance of 400 mid-cap U.S. companies.

• S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index is a subset of the broad market selected by the index sponsor representing the mid-cap developed market, excluding the United States.

• S&P Global Ex-U.S. SmallCap Index is an unmanaged index consisting of the bottom 20% of institutionally investable capital of developed and emerging countries, outside the United States.

• S&P Global Ex-U.S. Between $500 Million and $5 Billion Index is a subset of the broad market selected by the index sponsor representing the mid- and small-cap developed and emerging markets, excluding the United States.

Unlike mutual funds, indexes are not managed and do not incur fees or expenses. It is not possible to invest directly in an index.

Squirrel Chatter II: Agriculture's Amazing Progress

Following a conversation with two of our analysts regarding the prospects for several fertilizer companies, I decided to learn more about the history and current state of agriculture. According to Marcel Mazoyer and Laurence Roudart's, A History of World Agriculture,¹ farming began about 10,000 years ago. One would think that mankind is far down the learning curve in agriculture, and that productivity gains are ending. Surprisingly, quite the opposite is true. Most of the improvements in agriculture have occurred in the last 80 years.

Mazoyer and Roudart's history explains six dominant agricultural processes. The first two of these were employed during the first 8,000 years of agricultural history, obviously a time of very slow progress. Agriculture began with slash and burn techniques, whereby forest segments were successively burned and farmed for a few years until nutrients were depleted. Then, beginning in about 2500 B.C., farmers began using animal drawn scratch-plows and annually rotating land from planted to fallow in an attempt to maintain soil fertility. Other than in exceptionally fertile areas such as the lands replenished by the Nile River, these techniques barely enabled one farmer to feed one family.

Medieval farmers utilized better tools and techniques. They kept more animals and, with the help of wheeled carts and plows, used more animal-based fertilizers. Beginning in the sixteenth century, farmers began planting legumes to enhance nitrogen in the soil, further improving fertility by organic means and eliminating the need for fallowing. Productivity per farmer doubled with each of these developments, enabling the best farmers by the eighteenth century to feed an average of 20 people.

Farms became more mechanized after 1800, using metal plows, sowers, reapers and threshing machines. Transportation also improved allowing better fertilizers, that contained minerals like phosphate and potassium, to reach farmers. These minerals along with nitrogen helped to sustain crop yields. While mechanization doubled the acreage a farmer could cultivate, United States Department of Agriculture (USDA) data indicates that yields per acre of corn and wheat in the United States were flat from 1866, the date of data inception, well into the 1930s.

In the first half of the twentieth century, North American farmers started using motorized equipment, synthetic fertilizers and hybrid seeds. According to Giovanni Federico's, Feeding the World,² by 1950 farms in the United States and Canada had one tractor for every two farmers. Utilization of fertilizer grew six fold from 1900 to 1950. Hybrid wheat was grown on 87% of the planted acres in the United States in 1921, up from 14% in 1914. Hybrid corn crops jumped from 2% to 90% of acres planted from 1936 to 1945.³

After World War II these innovations spread. Worldwide chemical fertilizer usage grew nearly tenfold from 1950 to 2000. In most continents, over half of wheat, rice and corn acres were sown with high yield varieties by the year 2000. From 1950 to 2000, world agriculture production tripled, far outpacing population growth.⁴ USDA data indicates that from 1998 to 2008, wheat yields per acre averaged 41 bushels, triple the rate of 100 years ago, and corn yields quintupled to an average of 144 bushels. The best equipped farmers can now produce over four million pounds of grain and feed thousands!⁵

Launching a "Green Revolution" in Developing Countries

Rich countries had the means to adopt modern agricultural processes while poor regions struggled to advance. Leon Hesser's book, The Man Who Fed the World,⁶ describes how Dr. Norman Borlaug helped create the Green Revolution⁷ in many developing countries by improving plant varieties and increasing crop yields. For his efforts, Borlaug won a Nobel Peace Prize, the only one awarded in the twentieth century for work in agriculture.

Mexico redistributed land to poor peasants after its political revolution ended in 1918. However, its peasants remained poor and hungry for decades. In 1940, U.S. vice president elect, Henry Wallace, who had founded Hi-Bred Corn Company (now Pioneer Hi-Bred, a DuPont subsidiary), toured Mexico and was appalled by conditions there. He convinced the Rockefeller Foundation to sponsor efforts to adapt hybrid wheat and corn for Mexico and in 1943, the Mexican Government-Rockefeller Foundation Cooperative Agricultural Program was established.

The program hired Borlaug as its plant pathologist. Borlaug learned that a plant disease called wheat stem rust had halved Mexico's wheat production from 1939 to 1942. He set out to create high yielding hybrid wheat that was resistant to the disease. His program introduced three innovations. First, he planted successive hybrid crops in two locations each year, which both doubled the pace of progress and resulted in crops tolerant to varying conditions. Next, Borlaug crossed thousands of varieties of wheat, working to find the most resistant hybrids. He eventually developed 40 rust resistant varieties.

Third, Borlaug changed the architecture of wheat. He knew that many wheat varieties responded well to fertilizer but when yields exceeded roughly two tons per acre, plants became top-heavy and collapsed. Borlaug crossed over 20,000 varieties of wheat from around the world in his efforts to create high yielding wheat with shorter, stronger stems. He finally succeeded in 1953 by crossing rust-resistant Mexican seeds with Japanese dwarf wheat. Under ideal conditions, four tons of wheat per acre could be achieved. Mexico became self sufficient in wheat in 1956.

Having achieved success in Mexico, the Rockefeller Foundation pursued progress elsewhere, in partnership with the Ford Foundation, the United Nations and local governments. Pakistan and India were major beneficiaries. By 1970, 55% of Pakistan's wheat acreage and 35% of India's wheat acreage were sown with Mexican varieties. The Rockefeller and Ford Foundations also created the International Rice Research Institute, which began in 1960. By 1966 it developed a sturdy short-stemmed rice plant that, when fertilized sufficiently, yielded two- to three-times the rice it replaced. This rice was quickly adopted in India.

Borlaug was personally involved with the implementation of these programs. He understood that in addition to better seeds, farmers need fertilizer, credit and fair prices for their crops. Governments largely complied. As a result of the Green Revolution, many developing countries were substantial contributors to world agricultural growth.

Recent Conditions and Future Prospects

After reading so much about the amazing progress that has been made in agriculture, it was somewhat surprising to find an article in the June 2009 National Geographic titled, "The End of Plenty, The Global Food Crisis." It noted that global grain consumption exceeded production for seven of the last nine years and grain stockpiles plunged to a 20-year low of 61-days supply in 2007 prior to recovering to a meager 70-days supply in 2008. The price of wheat and corn tripled from 2005 to 2008, and the price of rice quintupled.

Demand recently grew more quickly than supply for several reasons. First, people in developing countries are becoming more prosperous and are eating more meat, causing grain consumption by livestock to rise rapidly. Second, use of ethanol as a gasoline additive or substitute has jumped. Some 30% of the 2008 U.S. corn crop was converted to ethanol instead of being available as food. Third, while world grain production hit records in 2008, growth in grain production has slowed somewhat since the year 2000 compared to prior decades.

Still, agriculture continues to find ways to meet the rising demand. Advancements in hybrid crops continue, and biotechnology is now creating crops with whole new characteristics. While conventional plant breeding is limited to crossing closely related species, biotech methods utilize genes from distant species. To date, two types of biotech crops have been commercialized, those resistant to herbicides and those resistant to insects.

Biotech crops were first made available in 1996 and by 2008 were planted in over 300 million acres, some 8% of global cropland in 25 countries, including 15 developing countries. That year, 85% of the corn crop in the United States came from biotech seeds. Farmers seem satisfied with biotech crops; nearly 100% keep planting biotech once they begin.⁸ Use of biotech versions of soybean, cotton, corn, canola and other crops increased farm income an estimated $10 billion in 2007 and biotech corn and soybean yields appear to be roughly 10% higher than conventional crops.⁹ The National Geographic story quotes a scientist with agricultural company Monsanto who predicts that biotechnology will double corn, soybean and cotton yields by 2030.

National Geographic also pointed out the downside of the Green Revolution. Yields in India have flattened since the mid-90s, and hybrid plant needs for water, fertilizer and pesticides have resulted in aquifer depletion, salinized soils and contamination of drinking water. However, new versions of biotech plants are in development, including versions likely to provide still higher yields, drought tolerance and salinized soil tolerance.

Not everyone agrees with the use of biotech crops. Critics have expressed doubts about productivity gains and have concerns about the possibility of a "Frankenfood" becoming toxic or creating an ecological disaster should some new plant become invasive. But numerous safeguards are in place, including rigorous approval processes. Countries that had prohibited biotech crops are now slowly introducing them. Increased adoption of biotech plants has had positive ecological effects, as higher yields reduce needs for additional crop acres and related deforestation, insect resistance reduces needs for pesticides, and herbicide resistance reduces fuel consumption and soil erosion by requiring less tillage.

Mankind's progress in agriculture has been truly amazing. We cannot revert back to previous agricultural processes, which are insufficient to feed a worldwide population of 6.7 billion. Instead, substantial investments in agriculture, and judicious use of new technologies, are needed to maintain impressive production gains in the future.

Columbia Acorn Funds News

Resumption of Securities Lending

Columbia Acorn Funds restarted its securities lending program during the second quarter. The domestic Funds briefly participated in securities lending in the third quarter of last year but suspended lending activities due to the turmoil in the financial markets at that time. As market conditions have stabilized somewhat, the Columbia Acorn Trust Board and Columbia Wanger Asset Management (CWAM) made the decision to begin securities lending again in June.

Securities lending has come under media scrutiny recently so we want to clearly state how CWAM administers the lending program. Fund shareholders receive all of the income generated by our lending program, net of modest fees charged by the lending agent to operate the program. The securities lending income benefits Fund shareholders by offsetting a portion of the Funds' operating expenses, which increases the Funds' total returns. The advisor charges no additional fees for administering this program.

As mentioned in our third quarter report last year, securities lending is the temporary lending of a Fund's portfolio securities to broker/dealers and other institutional investors. The Fund retains the benefits of owning the securities, including receipt of dividends or interest generated by the security. The Fund also receives a fee for the loan. The Fund may recall the loans at any time and may do so in order to vote proxies or to sell the loaned securities. Furthermore, borrowers provide the Fund with cash collateral that exceeds the value of the securities on loan. The Fund could lose money if it incurred a loss on the reinvestment of the cash collateral. To minimize this risk, cash collateral for the program is invested in the Dreyfus Government Cash Management Fund, a money market mutual fund. The securities lending agent is Goldman Sachs Agency Lending. Thus far, shareholders have received modest benefits and incurred no losses from the program.

Charles P. McQuaid

President and Chief Investment Officer
Columbia Wanger Asset Management, L.P.

The information and data provided in this analysis are derived from sources that we deem to be reliable and accurate. These views are not guarantees of future performance and involve certain risks, uncertainties and assumptions that are difficult to predict so actual outcomes and results may differ significantly from the views expressed. The views/opinions expressed in "Squirrel Chatter II" are those of the author and not of the Columbia Acorn Trust Board, are subject to change at any time based upon economic, market or other conditions, may differ from views expressed by other Columbia Management associates or other divisions of Bank of America and the respective parties disclaim any responsibility to update such views. These views may not be relied on as investment advice and, because investment decisions for a Columbia Acorn Fund are based on numerous factors, may not be relied on as an indication of trading intent on beha lf of any particular Columbia Acorn Fund.

¹ Mazoyer, Marcel and Roudart, Laurence, A History of World Agriculture, (New York, NY, Monthly Review Press, 2006).

² Federico, Giovanni, Feeding The World, (Princeton and Oxford, Princeton University Press, 2005).

³ Ibid, pg. 97.

⁴ Ibid, pgs. 55, 19.

⁵ Mazoyer, Marcel and Roudart, Laurence, op. cit., pg 11.

⁶ Hesser, Leon, The Man Who Fed The World, (Dallas, TX, Durban House, 2006).

⁷ The Green Revolution is defined by Mazoyer and Roudart as, "a variant of the contemporary agricultural revolution but without the large-scale motorization and mechanization, developed widely in the developing countries."

⁸ ISAAA Brief 39-2008: Executive Summary, "Global Status of Commercialized Biotech/GM Crops: 2008, The First Thirteen Years, 1996 to 2008," available at www.isaaa.org.

⁹ "GM crops: global, socio-economic and environmental impacts 1996-2007," a research paper written by Graham Brookes and Peter Barfoot of PG Economics Ltd, Dorchester, U.K., May 2009.

Understanding Your Expenses

As a Fund shareholder, you incur two types of costs. There are transaction costs, which generally include sales charges on purchases and may include redemption or exchange fees. There are also ongoing costs, which generally include investment advisory fees, distribution and service (Rule 12b-1) fees and other Fund expenses. The following information is intended to help you understand your ongoing costs of investing in the Columbia Acorn Funds and to compare these costs with the ongoing costs of investing in other mutual funds.

Analyzing Your Fund's Expenses

To illustrate these ongoing costs, we have provided examples and calculated the expenses paid by investors in the Class Z shares of the Columbia Acorn Funds for the last six months. The information in the following table is based on an initial investment of $1,000, which is invested at the beginning of the reporting period and held for the entire period. Expense information is calculated two ways and each method provides you with different results. The amount listed in the "Actual" column is calculated using each Fund's actual operating expenses and total return for the period. The amount listed in the "Hypothetical" column assumes that the return each year is 5% before expenses and then applies each Fund's actual expense ratio for the period to the hypothetical return. You should not use the hypothetical account values and expenses to estimate either your actual account balance at the end of the period or the expenses you paid during the reporting period. See the "Compare With Other Funds" information for details on using the hypothetical data.

January 1, 2009 – June 30, 2009

	Account value at the beginning of the period ($)				Account value at the end of the period ($)				Expenses paid during the period ($)				Fund's annualized expense ratio (%)*
*Class Z Shares*	Actual		Hypothetical		Actual		Hypothetical		Actual		Hypothetical		Actual
Columbia Acorn Fund		1,000.00		1,000.00		1,097.69		1,020.83		4.16		4.01		0.80
Columbia Acorn International		1,000.00		1,000.00		1,213.08		1,019.64		5.71		5.21		1.04
Columbia Acorn USA		1,000.00		1,000.00		1,080.48		1,019.54		5.47		5.31		1.06
Columbia Acorn International Select		1,000.00		1,000.00		1,096.00		1,018.74		6.34		6.11		1.22
Columbia Acorn Select		1,000.00		1,000.00		1,243.78		1,019.64		5.79		5.21		1.04
Columbia Thermostat Fund		1,000.00		1,000.00		1,076.71		1,023.55		1.29		1.25		0.25

Expenses paid during the period are equal to each Fund's annualized expense ratio, multiplied by the average account value over the period and then multiplied by the number of days in the Fund's most recent fiscal half-year and divided by 365.

Had the investment advisor and/or any of its affiliates not waived fees or reimbursed a portion of expenses, account value at the end of the period would have been reduced for Columbia Thermostat Fund.

It is important to note that the expense amounts shown in the table are meant to highlight only ongoing costs of investing in the Funds and do not reflect any transaction costs, such as sales charges, redemption or exchange fees. Therefore, the hypothetical examples provided may not help you determine the relative total costs of owning different funds. If these transaction costs were included, your costs would have been higher.

Columbia Thermostat Fund's expenses do not include fees and expenses incurred by the Fund from the underlying portfolio funds in which it invests.

*For the six months ended June 30, 2009.

Compare With Other Funds

Since all mutual funds are required to include the same hypothetical calculations about expenses in shareholder reports, you can use this information to compare the ongoing cost of investing in the Funds with other funds. To do so, compare the 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of other funds. As you compare hypothetical examples of other funds, it is important to note that hypothetical examples are meant to highlight the continuing costs of investing in a fund and do not reflect any transaction costs, such as sales charges, or redemption or exchange fees.

Estimating Your Actual Expenses

To estimate the expenses that you actually paid over the period, first you will need your account balance at the end of the period:

• For shareholders who receive their account statements from Columbia Management Services, Inc., your account balance is available online at columbiafunds.com or by calling Shareholder Services at (800) 922-6769.

• For shareholders who receive their account statements from their brokerage firm, contact your brokerage firm to obtain your account balance.

1. Divide your ending account balance by $1,000. For example, if an account balance was $8,600 at the end of the period, the result would be 8.6.

2. In the section of the table titled "Expenses paid during the period," locate the amount for your Fund. You will find this number is in the column labeled "Actual." Multiply this number by the result from step 1. Your answer is an estimate of the expenses you paid on your account during the period.

Columbia Acorn Fund

In a Nutshell



Charles P. McQuaid				Robert A. Mohn

Lead Portfolio Manager				Co-Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

Coach	1.4	%
ITT Educational Services	1.2	%
Southwestern Energy	1.2	%
People's United	1.1	%
Bally Technologies	1.0	%
Fugro	1.0	%
FMC Technologies	1.0	%
AmeriCredit	0.8	%
Myriad Genetics	0.6	%
OLAM International	0.4	%
Hexagon	0.4	%
Pacific Rubiales Energy	0.4	%

The stock market did well in the second quarter, jumping up from what appeared to be oversold levels. Columbia Acorn Fund returned 20.90%, earning its best quarterly gain since the fourth quarter of 1999! The Fund returned somewhat more than its primary benchmark, the Russell 2500, which rose 20.27%. During the first half of 2009, the Fund grew 9.77%, nicely outperforming the 6.52% gain of the Russell 2500. As shown on Page 1, Columbia Acorn Fund also beat most other benchmarks in both periods.

As might be expected during a market reversal, several important stocks changed direction during the second quarter. Handbag and accessories designer and retailer Coach was the Fund's largest dollar winner in the quarter, up 62% as the company cut costs and repositioned its product line, which resulted in earnings dropping less than most analysts expected. Used car lender AmeriCredit achieved second place dollar winnings for both the quarter and the half, up 131% and 77% respectively, on news of a successful refinancing. Gaming machine maker Bally Technologies scored a more than 60% gain in the second quarter, earning third place dollar winnings thanks to its strong new product pipeline. All three stocks had been down 20% to 23% in the first quarter.

In contrast, three stocks that we cited as fine performers in the first quarter ended up as Columbia Acorn Fund's largest dollar losers in the second quarter. ITT Educational Services, People's United and Myriad Genetics each fell 15% to 20%. While ITT Educational's earnings were excellent, fears about student loan financing and additional regulation resurfaced. Connecticut bank People's United reported rising credit defaults. Default rates remained under half the rates of the bank's peers, but the news was bad, and the stock dropped. Myriad fell in response to disappointing revenue growth; sales of its genetic tests appear to be more sensitive to the economy than expected. We cut positions in each by over 20% in the first half, reducing dollar losses.

Energy stocks did well in both the quarter and the half as oil prices jumped. FMC Technologies rose 20% in the quarter, and its 55% gain in the half lifted it into the Fund's largest dollar winner position. Fugro, another offshore oil service company, gained 38% in the quarter and 53% in the half, earning the fourth place dollar winner position year to date. Gas producer Southwestern Energy was also hot, rising 31% in the quarter and 34% in the half, taking fifth place in dollar gains for the half.

Foreign stocks outperformed in both the second quarter and the first half of the year. Energy stocks helped a lot; Fugro was the top foreign dollar winner in both periods. Oil producer Pacific Rubiales Energy surged more than 110% in the quarter and more than 350% in the half on expectations that production will rise rapidly. Measurement equipment company Hexagon jumped over 80% in both the quarter and the half as business appeared to be bottoming or improving in several countries. Agricultural supply chain manager OLAM International's stock surged over 70% in both periods as fears about customers' abilities to finance purchases abated. Foreign stocks were 9.5% of the Fund's assets at the end of the second quarter, up from 7.1% at the end of March.

Stocks of small- and mid-cap companies pose special risks, including possible illiquidity and greater price volatility than stocks of larger, more established companies. International investing involves special risks, including foreign taxation, currency risks, risks associated with possible differences in financial standards and other risks associated with future political and economic developments.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn Fund (ACRNX)

At a Glance

Performance data quoted represents past performance and current performance may be higher or lower. Past performance is no guarantee of future results. The investment return and principal value of an investment in the Fund will fluctuate so that Fund shares, when redeemed, may be worth more or less than their original cost. Performance results reflect any fee waivers or reimbursements of Fund expenses by the investment advisor and/or any of its affiliates. Absent these fee waivers or expense reimbursement arrangements, performance results would have been lower. Please visit columbiafunds.com for daily and most recent month-end updates.

Pretax and After-tax Average Annual Total Returns (Class Z)

through June 30, 2009

*Inception 6/10/70*	Year to date*			1 year			5 years			10 years
Returns before taxes		9.77	%		-25.83	%		0.95	%		7.25	%
Returns after taxes on distributions		9.77			-25.91			0.11			6.01
Returns after taxes on distributions and sale of fund shares		6.35			-16.70			1.01			6.09
Russell 2500 Index (pretax)**		6.52			-26.72			-0.93			3.67

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the additional tax impact of long-term gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class Z shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes.

The Fund's Class Z shares annual operating expense ratio, as stated in the current prospectus, is 0.76%.

*Year to date data is not annualized.

Columbia Acorn Fund Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn Fund Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	Coach Designer & Retailer of Branded Leather Accessories	1.4%
2.	Crown Castle International Communications Towers	1.4%
3.	Ametek Aerospace/Industrial Instruments	1.3%
4.	Donaldson Industrial Air Filtration	1.2%
5.	ITT Educational Services Post-secondary Degree Services	1.2%
6.	Expeditors International of Washington International Freight Forwarder	1.2%
7.	Southwestern Energy Oil & Gas Producer	1.2%
8.	People's United Connecticut Savings & Loan	1.1%
9.	Alexion Pharmaceuticals Biotech Focused on Orphan Diseases	1.1%
10.	Bally Technologies Slot Machines & Software	1.0%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn Fund (Class Z)

June 10, 1970 through June 30, 2009

This graph compares the results of $10,000 invested in Columbia Acorn Fund at inception on June 10, 1970 to the S&P 500 Index and to an initial $31,777 investment in the Russell 2500 Index on the index's December 31, 1978 inception date. Although the indexes are provided for use in assessing the Fund's performance, the Fund's holdings may differ significantly from those in the indexes. The indexes are unmanaged and returns for both the indexes and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $11.7 billion

*A $10,000 investment in Columbia Acorn Fund at inception appreciated to $31,777 on December 31, 1978, the inception date of the Russell 2500 Index. For comparison with the Russell 2500 Index, we assigned the index the same value as the Fund at index inception.

**Although the Fund typically invests in small- and mid-sized companies, the comparison to the S&P 500 Index is presented to show performance against a widely recognized market index over the life of the Fund.

Columbia Acorn International

In a Nutshell



P. Zachary Egan				Louis J. Mendes III

Co-Portfolio Manager				Co-Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

Serco	1.1	%
Capita Group	1.1	%
Educomp Solutions	0.9	%
Central European Distribution	0.8	%
Jain Irrigation Systems	0.7	%
RexLot Holdings	0.6	%

Columbia Acorn International rose 33.30% in the second quarter, slightly trailing the 34.15% rise of its primary benchmark, the S&P Global Ex-U.S. Between $500 Million and $5 Billion Index. Year to date, the Fund was up 21.31%, 3.23% behind its primary benchmark. Small-cap international stocks led larger-cap international stocks, as exemplified by the MSCI EAFE Index, which was up 25.43% in the quarter and 7.95% year to date.

While coming on the heels of a severe sell-off in 2008, an absolute return north of 30% in a single quarter is always pleasing. This remarkable reversal in market sentiment in the second quarter appears to reflect decreasing anxiety about our economic future, as credit markets show signs of life, in a context of attractive valuations. While the stock market has historically done a good job of anticipating changes in economic fundamentals by several quarters, it is worth noting that the majority of the companies we follow have reported few sightings of "green shoots" presaging a return to global growth. Indeed, the International Monetary Fund expects global economic activity to contract by 1.4% in 2009 before expanding 2.5% in 2010. The major exception to this has been the emerging markets of non-Japan Asia and Latin America. In these economies the sentiment is now distinctly upbeat. The rapid implementation of a sizeable governm ent stimulus package in China, and an election outcome in India perceived to endorse further economic liberalization, drove this enthusiasm.

Investments in emerging markets, which constitute about one quarter of the Fund's assets, posted the strongest returns, with the Fund's holdings in Asia ex-Japan up nearly 50% in the quarter and roughly 45% year to date. The Fund's Indian stocks were up just short of 80% in the quarter and 66% in the half year, led by Jain Irrigation Systems. Jain is the country's leading manufacturer of micro-irrigation systems and is a beneficiary of government policies that support efficient irrigation. Educomp Solutions provides multimedia educational content to Indian classrooms and is a recent addition to the portfolio. Its stock was also a big winner. Consumer stocks in developing markets, a long-time theme in the Fund, were also notable standouts: Central European Distribution, a Polish spirits company, more than doubled in the quarter after renegotiating agreements and financing related to a Russian acquisition. In the half year this st ock was up 35%. RexLot Holdings, which provides systems and services to the Chinese lottery market, tripled after several punishing quarters on evidence of tangible progress in its core business. Its stock was up 224% through June 30, 2009.

While still making a positive contribution to absolute return, the Fund's overweight position in health care stocks failed to keep up with a buoyant market. These companies' fortunes tend to be less correlated with actual or perceived changes in economic activity. Stock selection, however, was decidedly unhelpful in the pharmaceutical and biotech sectors, where after the quarter end, we made some changes. Japan was a drag on absolute return in the half year and the quarter, but keep in mind that Japan fell substantially less than most regions in 2008 and, therefore, had less ground to make up.

The Fund's holdings in the United Kingdom and Ireland fell short in the half year. The Fund held large positions in Serco and Capita Group, service providers with highly predictable revenues and considerable exposure to government contracts. Their comparatively low risk profiles proved to be a liability in an environment in which the riskiest stocks rallied the most.

On earnings adjusted for cyclicality and on other valuations measures, we believe that international small-cap stocks now trade at a modest discount to their 10-year average.

International investing involves special risks, including foreign taxation, currency risks, risks associated with possible differences in financial standards and other risks associated with future political and economic developments. Stocks of small- and mid-cap companies pose special risks, including possible illiquidity and greater price volatility than stocks of larger, more established companies. Investing in emerging markets may involve greater risks than investing in more developed countries. In addition, concentration of investments in a single region may result in greater volatility.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn International (ACINX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Class Z)

through June 30, 2009

*Inception 9/23/92*	Year to date*			1 year			5 years			10 years
Returns before taxes		21.31	%		-28.00	%		8.47	%		6.96	%
Returns after taxes on distributions		20.51			-28.47			7.59			5.95
Returns after taxes on distributions and sale of fund shares		13.85			-18.20			7.58			5.96
S&P Global Ex-U.S. Between $500 Million and $5 Billion Index (pretax)**		24.54			-26.45			7.13			6.80

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

The Fund's Class Z annual operating expense ratio, as stated in the current prospectus, is 0.96%.

*Year to date data is not annualized.

Columbia Acorn International Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn International Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	Naspers (South Africa) Media in Africa & Other Emerging Markets	1.6%
2.	OLAM International (Singapore) Agriculture Supply Chain Manager	1.5%
3.	Kansai Paint (Japan) Paint Producer in Japan, India, China & Southeast Asia	1.4%
4.	Hong Kong Exchanges and Clearing (Hong Kong) Hong Kong Equity & Derivatives Market Operator	1.3%
5.	Serco (United Kingdom) Facilities Management	1.1%
6.	Intertek Group (United Kingdom) Testing, Inspection & Certification Services	1.1%
7.	Capita Group (United Kingdom) White Collar, Back Office Outsourcing	1.1%
8.	Imtech (Netherlands) Engineering & Technical Services	1.1%
9.	Hexagon (Sweden) Measurement Equipment	1.1%
10.	Singapore Exchange (Singapore) Singapore Equity & Derivatives Market Operator	1.0%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn International (Class Z)

September 23, 1992 through June 30, 2009

This graph compares the results of $10,000 invested in Columbia Acorn International at inception on September 23, 1992 to the S&P Global Ex-U.S. Between $500 Million and $5 Billion Index. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings may differ significantly from those in the index. The index is unmanaged and returns for both the index and Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $3.3 billion

Columbia Acorn USA

In a Nutshell

Robert A. Mohn

Lead Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

FMC Technologies	2.1	%
ITT Educational Services	1.9	%
Atwood Oceanics	1.6	%
Micros Systems	1.6	%
Bally Technologies	1.6	%
AmeriCredit	1.4	%
Mettler Toleldo	1.3	%
Valley National Bancorp	1.0	%
FLIR Systems	1.0	%
Lakeland Financial	0.7	%
Cephalon	0.6	%
Myriad Genetics	0.6	%
Berkshire Hills Bancorp	0.5	%
MB Financial	0.4	%
Associated Banc-Corp	0.2	%
Immucor	0.2	%

Columbia Acorn USA ended the second quarter up 19.42%. This compares to a 20.69% gain by the Fund's primary benchmark, the Russell 2000 Index. Year to date, the Fund's 8.05% return was well ahead of the benchmark, which gained 2.64%. Small-cap stocks significantly outperformed large caps. The large-cap focused S&P 500 Index gained 15.93% in the quarter, 4.76% behind the Russell 2000 Index.

Winners for the quarter and half year came from a variety of sectors. Auto lender AmeriCredit returned from the near-dead as the market reacted favorably to its positive earnings announcement and to news that the company was able to renegotiate its bank credit lines. The stock was up 131% in the second quarter and 77% year to date. Bally Technologies, a slot machine manufacturer, gained more than 60% in the quarter, and was up 25% for the half year as the market recognized its strong new product pipeline. Atwood Oceanics, an offshore drilling contractor, was helped by the rebound in oil prices, which fueled a 53% gain in the quarter and a 69% return for the half year. FMC Technologies, an oil and gas wellhead manufacturer, also benefited from the oil price bounce, gaining 20% in the quarter and topping 55% for the half year.

Mettler Toledo had a strong second quarter, gaining 50%. This manufacturer of laboratory equipment has been hurt by the weak economy, but implemented a dramatic cost reduction program that boosted earnings. Cost controls also helped at Micros Systems, a provider of information systems for restaurants and hotels. Micros's earnings were down just a penny from the prior year. This ability to nearly maintain earnings, while operating in an extremely strained sector, got a positive nod from the market. Its stock gained 35% in the quarter and 55% for the half year.

Our health care stocks were weak in the quarter. Myriad Genetics produces genetic diagnostic tests and has seen its sales growth rate fall as patients defer elective tests to save money. Immucor, a maker of blood typing and screening products, saw its stock collapse when news broke that it was under investigation for potential anti-trust violations. Pharmaceutical company Cephalon fell on fears that pending legislation and regulatory actions could have a negative impact on pharmaceutical companies.

The largest detractor from performance in the quarter was ITT Educational Services, which was off 17%. A cloud is hanging over private education companies as proposed legislation could negatively impact these organizations.

Year to date, Fund bank holdings came up short. Community banks MB Financial, Valley National Bancorp, Berkshire Hills Bancorp, Lakeland Financial and Associated Banc-Corp all made the Fund's loser list as high default rates took down the whole group. Losses in these stocks ranged from 19% to 63%. Infrared camera manufacturer FLIR Systems also declined after failing to win a new military contract. Its stock fell 26%.

The second quarter brought springtime to the United States and to the stock and bond markets. Debt markets loosened up quite a bit during the quarter, with some corporate bond spreads dropping back below levels of one year ago. Credit markets led the stock market down last year; they may be leading us the other way in 2009.

Stocks of small- and mid-cap companies pose special risks, including possible illiquidity and greater price volatility than stocks of larger, more established companies.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn USA (AUSAX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Class Z)

through June 30, 2009

*Inception 9/4/96*	Year to date*			1 year			5 years			10 years
Returns before taxes		8.05	%		-28.24	%		-1.81	%		4.02	%
Returns after taxes on distributions		8.05			-28.24			-2.31			3.50
Returns after taxes on distributions and sale of fund shares		5.23			-18.36			-1.35			3.48
Russell 2000 Index (pretax)**		2.64			-25.01			-1.71			2.38

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

The Fund's Class Z annual operating expense ratio, as stated in the current prospectus, is 1.01%.

*Year to date data is not annualized.

Columbia Acorn USA Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn USA Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	Crown Castle International Communications Towers	2.8%
2.	ESCO Technologies Automatic Electric Meter Readers	2.6%
3.	FMC Technologies Oil & Gas Wellhead Manufacturer	2.1%
4.	Ametek Aerospace/Industrial Instruments	2.0%
5.	tw telecom Fiber Optic Telephone/Data Services	1.9%
6.	ITT Educational Services Post-secondary Degree Services	1.9%
7.	Informatica Enterprise Data Integration Software	1.7%
8.	Global Payments Credit Card Processor	1.7%
9.	Atwood Oceanics Offshore Drilling Contractor	1.6%
10.	Micros Systems Information Systems for Restaurants & Hotels	1.6%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn USA (Class Z)

September 4, 1996 through June 30, 2009

This graph compares the results of $10,000 invested in Columbia Acorn USA at inception on September 4, 1996 to the Russell 2000 Index. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings may differ significantly from those in the index. The index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $1.1 billion

Columbia Acorn International Select

In a Nutshell

Christopher J. Olson

Lead Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

Naspers	4.9	%
Serco	4.7	%
Pacific Rubiales Energy	3.3	%
Intertek Group	3.3	%
Nintendo	2.6	%
Jupiter Telecommunications	2.0	%
Hexagon	1.8	%
Cephalon	1.4	%

Columbia Acorn International Select ended the second quarter up 23.44%, underperforming its primary benchmark, the S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index, which gained 28.70%. Year to date, the Fund was up 9.60%, while its benchmark posted a 14.93% return. The Fund's less cyclical portfolio, which helped performance during the recent market crash, held the Fund back as investors rushed into riskier assets.

Pacific Rubiales Energy, an oil production and exploration company operating in Colombia, was a top contributor to Fund performance, up 110% in the second quarter and more than 350% year to date. The stock benefited from the rebound in oil prices and on expectations that its production will continue to rise rapidly. Naspers, a media company with assets in South Africa and other emerging markets, was also strong, returning 55% for the quarter and 42% year to date. Naspers announced strong results through the end of March and also benefited from its 35% holding in the rapidly growing Chinese internet company Tencent. U.K. facilities management company Serco ended the quarter up 32% and was up just over 7% year to date. In June, Serco announced a series of major contract wins that continue to drive double-digit revenue growth. Swedish measurement equipment manufacturer Hexagon was up over 80% for the quarter and the half year on ex pectations that we have seen the worst of the economic crisis. Finally, Intertek Group, a U.K. provider of testing, inspection and certification services, rose 39% in the quarter and 56% year to date as increasing government regulations continued to drive growth in its consumer products testing business.

Health care holdings were among the Fund's worst performers as investors moved away from these more defensive businesses. U.S. pharmaceutical company Cephalon, Swiss orthopedic surgery materials manufacturer, Synthes and U.S. biotech company BioMarin fell between 20% and 31% in the half. We opted to sell the Fund's positions in Synthes and BioMarin. Japan's Nintendo, a maker of gaming software and hardware, was also off for both periods, down 5% in the quarter and 27% year to date as growth in its Wii product slowed. Japanese cable service provider Jupiter Telecommunications rebounded in the second quarter with a gain of 13%, but it was not enough to offset first quarter declines. The stock was down 28% year to date as investors sold last year's strong performers to fund purchases of more cyclical stocks.

Volatility has been, and is likely to continue to be, a defining feature of the global equity markets. High debt levels, loose monetary policies, large fiscal stimulus plans, changing government regulations, rapidly evolving business environments and other factors will keep investors guessing. We will continue to focus our efforts on finding those companies that we believe can manage such turbulence and adequately reward shareholders over the long term.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn International Select (ACFFX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Class Z)

through June 30, 2009

*Inception 11/23/98*	Year to date*			1 year			5 years			10 years
Returns before taxes		9.60	%		-34.62	%		7.10	%		5.54	%
Returns after taxes on distributions		9.14			-34.89			6.77			5.34
Returns after taxes on distributions and sale of fund shares		6.24			-22.50			6.30			4.92
S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index (pretax)**		14.93			-30.16			4.30			5.24

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

The Fund's Class Z annual operating expense ratio, as stated in the current prospectus, is 1.21%.

*Year to date data is not annualized.

Columbia Acorn International Select Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn International Select Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	Naspers (South Africa) Media in Africa & Other Emerging Markets	4.9%
2.	Serco (United Kingdom) Facilities Management	4.7%
3.	Capita Group (United Kingdom) White Collar, Back Office Outsourcing	3.7%
4.	Israel Chemicals (Israel) Producer of Potash, Phosphates, Bromine, & Specialty Chemicals	3.5%
5.	Pacific Rubiales Energy (Canada) Oil Production & Exploration in Colombia	3.3%
6.	Intertek Group (United Kingdom) Testing, Inspection & Certification Services	3.3%
7.	Potash Corp. of Saskatchewan (Canada) World's Largest Producer of Potash	3.2%
8.	NHN (South Korea) South Korea's Largest Online Search Engine	2.9%
9.	Kansai Paint (Japan) Paint Producer in Japan, India, China & Southeast Asia	2.7%
10.	Alexion Pharmaceuticals (United States) Biotech Focused on Orphan Diseases	2.7%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn International Select (Class Z)

November 23, 1998 through June 30, 2009

This graph compares the results of $10,000 invested in Columbia Acorn International Select at inception on November 23, 1998 to the S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings may differ significantly from those in the index. The index and Fund returns include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $336.9 million

Columbia Acorn Select

In a Nutshell

Ben Andrews

Lead Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

ITT Educational Services	5.5	%
Pacific Rubiales Energy	5.3	%
Safeway	4.6	%
Hertz	4.1	%
Tetra Technologies	3.6	%
Expedia	3.0	%
Waste Management	2.8	%
MF Global	2.4	%
Conseco	2.4	%
Discover Financial Services	0.9	%
SBA Communications	0.8	%
Steelcase	0.8	%
Gran Tierra Energy	0.5	%
Princeton Review	0.3	%

Columbia Acorn Select gained 28.11% in the second quarter, which was 9.36% more than the Fund's primary benchmark, the S&P MidCap 400 Index, which rose 18.75%. Mid-cap stocks outperformed large caps. The S&P 500 Index was up 15.93%.

In our fourth quarter 2008 report, we mentioned positioning the portfolio in a barbell fashion. We saw many companies trading at low valuations due to a perceived bankruptcy risk, a fear driven by the tight credit markets. These undervalued, completely battered companies in the Fund's portfolio made up one side of the barbell, and at the other end we had companies that were solid franchises with little to no credit risk. If the economy kept losing ground, we felt these solid franchises would hold up better than most and the already battered companies wouldn't go down much more unless they went bankrupt (they were a much smaller dollar amount in the portfolio than the solid franchises). However, if the economy stabilized or improved, we would see the lending market re-open and bankruptcy risk lessen, causing the battered companies to explosively rise. The latter scenario describes what happened in the second quarter.

Looking at some of the Fund's top gainers in the quarter, we had five stocks that each added 2% or more return to our portfolio and each of these stocks was at the undervalued end of our barbell. They included Tetra Technologies, Pacific Rubiales Energy, Hertz, Conseco and Expedia. On the downside, ITT Educational Services cost the Fund 1.7% of performance. ITT, one of the solid franchises with little credit risk, held up well last year but pulled back as money flowed into the riskier stocks in the second quarter and as proposed legislation threatened to negatively impact the private education sector.

Columbia Acorn Select's year-to-date performance was a positive 24.38% vs. gains of 8.47% for the S&P MidCap 400 Index and 3.16% for the S&P 500 Index. Looking at the drivers of this solid outperformance, we see large gains in Pacific Rubiales Energy, MF Global, Expedia and Tetra Technologies. On the downside, Conseco, Safeway, Cephalon and Waste Management were the Fund's biggest detractors to year-to-date performance.

During the quarter we added several new names: Gran Tierra Energy, Discover Financial Services, Princeton Review, SBA Communications and Steelcase. We sold three positions: Cephalon, Knoll and Tellabs.

The credit markets continue to gradually re-open, which is positive, but many companies can still only issue credit based on federal programs and guarantees. Hopefully in the coming few quarters these programs will be unnecessary for companies to access the credit markets. Though we have rebuilt some of our capital from last year's collapse, we are still cautious; the Fund's cash levels are currently at 5% and could possibly trend higher over the coming months. Furthermore, in order to reduce risk, we've cut top position sizes to between 3% and 6% of the Fund, down from the prior 6% to 9% range. I see the fixed-income market facing challenges too that include an explosion in Treasury debt issuance. I also worry about a possible return of energy price inflation in the next couple of years.

I believe the market should grind higher in the coming months, but our economy is still weak and more excessive volatility probably lies ahead. We will continue to review and fine-tune our approach to try and get the most out of the markets as we struggle through the rough patches.

Risks include stock market fluctuations due to economic and business developments. The Fund also has potentially greater price volatility due to the Fund's concentration in a limited number of stocks of mid-size companies. The Fund is a non-diversified fund and may, therefore, have a greater risk of loss from a few issuers than a similar fund that invests more broadly. The Fund may not operate as a non-diversified fund at all times. International investments involve greater potential risks, including less regulation, currency fluctuations, economic instability and political developments.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn Select (ACTWX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Class Z)

through June 30, 2009

*Inception 11/23/98*	Year to date*			1 year			5 years			10 years
Returns before taxes		24.38	%		-32.90	%		0.26	%		5.31	%
Returns after taxes on distributions		24.38			-32.90			-0.11			4.85
Returns after taxes on distributions and sale of fund shares		15.85			-21.38			0.33			4.56
S&P MidCap 400 Index (pretax)**		8.47			-28.02			0.36			4.62

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

The Fund's Class Z annual operating expense ratio, as stated in the current prospectus, is 0.95%.

*Year to date data is not annualized.

Columbia Acorn Select Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn Select Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	ITT Educational Services Post-secondary Degree Services	5.5%
2.	Pacific Rubiales Energy (Canada) Oil Production & Exploration in Colombia	5.3%
3.	SkillSoft Web-based Learning Solutions (E-Learning)	4.8%
4.	Safeway Supermarkets	4.6%
5.	Hertz Largest U.S. Rental Car Operator	4.1%
6.	Quanta Services Electrical & Telecom Construction Services	3.9%
7.	Tetra Technologies U.S.-based Service Company with Life of Field Approach	3.6%
8.	Expedia Online Travel Services Company	3.0%
9.	Coach Designer & Retailer of Branded Leather Accessories	2.9%
10.	Career Education Post-secondary Education	2.8%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn Select (Class Z)

November 23, 1998 through June 30, 2009

This graph compares the results of $10,000 invested in Columbia Acorn Select at inception on November 23, 1998 to the S&P MidCap 400 Index. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings differ significantly from those in the index. The index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $1.5 billion

Columbia Thermostat Fund

In a Nutshell

Charles P. McQuaid

Lead Portfolio Manager

A "fund of fund" bears its allocable share of the costs and expenses of the underlying funds in which it invests. Such funds are thus subject to two levels of fees and potentially higher expense ratios than would be associated with a fund that invests and trades directly in financial instruments under the direction of a single manager.

Columbia Thermostat Fund ended the second quarter up 19.33%, outperforming the 15.93% gain in the S&P 500 Index, the Fund's primary stock benchmark, and the 1.78% return of the Barclays Capital U.S. Aggregate Bond Index, the Fund's primary bond benchmark. Year to date the Fund was up 7.67%, well ahead of the 3.16% gain of the S&P 500 Index and the 1.90% return for the Barclays Capital U.S. Aggregate Bond Index.

Among the underlying stock funds in which the Fund invests, Columbia Acorn International offered very strong performance for the quarter, up 33.30%, and half year, up 21.31%. Columbia Acorn Select also came back strong with a 28.11% second quarter gain and 24.38% year-to-date return. The Fund remained 100% invested in stock funds throughout the second quarter. The full stock exposure allowed Columbia Thermostat Fund to reap the rewards of the equity market rally that began in early March and continued through period end.

The recent market turbulence challenged the Fund's design. Had we known how far the market would plunge, we might have changed the allocation table and put more bond funds into Columbia Thermostat. Fearing sales of stock funds at or near what could have been a market bottom, we waited. The patience appears to have paid off. As we completed this report on August 10, 2009, the S&P 500 Index had topped 1,000, recovering from its low of 667. This increase triggered a reallocation on July 24, 2009, to 95% stock funds and 5% bond funds, the Fund's first reallocation since October 10, 2008. With the S&P 500 Index back within the range of the current reallocation table, Thermostat will adjust for future market moves, selling stocks on strength and buying on weakness.

Results of the Funds Owned in Columbia Thermostat Fund as of June 30, 2009

Stock Funds Fund	Weightings in category			2nd quarter			Year to date returns to 6/30/09
Columbia Acorn Fund		15	%		20.90	%		9.77	%
Columbia Acorn Select		10	%		28.11	%		24.38	%
Columbia Marsico Growth Fund		15	%		15.22	%		4.70	%
Columbia Acorn International		15	%		33.30	%		21.31	%
Columbia Dividend Income Fund		20	%		12.31	%		-0.86	%
Columbia Large Cap Enhanced Core Fund		25	%		15.74	%		1.86	%
*Weighted Average* *Equity Return/Loss*		*100*	%		*19.54*	%		*7.90*	%

Columbia Thermostat Fund did not hold bond funds in the second quarter or year-to-date periods.

The value of an investment in the Fund is based primarily on the performance of the underlying portfolio funds and the allocation of the Fund's assets among them. An investment in the underlying portfolio funds may present certain risks, including stock market fluctuations that occur in response to economic and business developments; and a greater degree of social, political and economic volatility associated with international investing. Stocks of small- and mid-cap companies pose special risks, including possible illiquidity and greater price volatility than stocks of larger, more established companies. Value stocks may also be subject to specific business risks that have caused the stocks to be out of favor. Lower-rated and medium quality debt securities are more speculative and incur more risk. International investing involves special risks, including foreign taxation, currency risks, risks associated with possible differ ences in financial standards and other risks associated with future political and economic developments. Changes in interest rates and changes in the financial strength of issuers of lower-rated bonds may also affect underlying fund performance. The Fund is also subject to the risk that the investment advisor's decisions regarding asset classes and underlying portfolio funds will not anticipate market trends successfully, resulting in a failure to preserve capital or lower total return. In addition, the Fund may buy and sell shares of the portfolio funds frequently. This may result in higher transaction costs and additional tax liability. This is not an offer of the shares of any other mutual fund mentioned herein.

Columbia Thermostat Fund (COTZX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Class Z)

through June 30, 2009

*Inception 9/25/02*	Year to date*			1 year			5 year			Life of fund
Returns before taxes		7.67	%		-21.62	%		0.17	%		3.86	%
Returns after taxes on distributions		7.55			-22.28			-1.65			2.40
Returns after taxes on distributions and sale of fund shares		4.99			-13.89			-0.44			2.84
S&P 500 Index (pretax)**		3.16			-26.21			-2.24			3.75
Barclays Capital U.S. Aggregate Bond Index (pretax)**		1.90			6.05			5.01			4.59
Barclays Capital U.S. Intermediate Credit Bond Index (pretax)		7.53			4.28			4.04			4.45
Lipper Flexible Portfolio Funds Index (pretax)		7.59			-21.04			1.16			5.21

All results shown assume reinvestment of distributions.

**The Fund's primary stock and bond benchmarks, respectively.

The Fund's Class Z annual operating expense ratio, as stated in the current prospectus, reflects a contractual expense waiver or reimbursement that expires April 30, 2010. Expense ratios without and with the contractual waiver, including fees and expenses associated with the Fund's investment in other investment companies, are 1.05% and 0.97%, respectively. Absent the waiver or reimbursement, performance results would have been lower.

*Year to date data is not annualized.

Columbia Thermostat Fund Portfolio Weightings

as a percentage of assets in each investment category, as of 6/30/09

The Growth of a $10,000 Investment in Columbia Thermostat Fund (Class Z)

September 25, 2002 through June 30, 2009

This graph compares the results of $10,000 invested in Columbia Thermostat Fund at inception on September 25, 2002 to the S&P 500 Index, the Barclays Capital U.S. Aggregate Bond Index, the Barclays Capital U.S. Intermediate Credit Bond Index and the Lipper Flexible Portfolio Funds Index. Although the indexes are provided for use in assessing the Fund's performance, the Fund's holdings differ significantly from those in the indexes. The Barclays Capital U.S. Aggregate Bond Index became the Fund's primary benchmark for debt securities effective July 1, 2008. The Fund changed to this debt benchmark because the advisor believes it is a more appropriate comparison to the Fund's investments. The Indexes are unmanaged and returns for the indexes and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distrib utions or on a sale of Fund shares.

Total Net Assets of the Fund: $125.3 million

Columbia Acorn Fund

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Information
AboveNet		0		100,000
Actuate		2,500,000		2,785,803
Art Technology Group		0		885,000
Blue Coat Systems		0		400,576
CommScope		0		1,085,000
Entegris		3,000,000		3,750,000
Eutelsat (France)		0		250,000
F5 Networks		0		665,000
Informatica		5,500,000		6,700,000
IXYS		2,035,000		2,135,000
ManTech International		180,000		225,000
Mettler Toledo		1,300,000		1,385,000
Monolithic Power Systems		315,000		645,000
Netgear		870,000		970,000
Novell		12,300,000		12,500,000
ON Semiconductor		2,914,000		3,384,000
SBA Communications		0		1,000,000
Singapore Exchange (Singapore)		3,400,000		10,000,000
VisionChina Media - ADR (China)		2,000,000		2,700,000
WNS - ADR (India)		39,325		709,260
Industrial Goods & Services
Aalberts Industries (Netherlands)		2,777,000		2,869,585
Albemarle		1,350,000		1,530,000
Carbone Lorraine (France)		189,580		515,380
Celanese		0		450,000
Drew Industries		1,324,000		1,600,000
FreightCar America		0		225,000
GrafTech International		0		1,700,000
HEICO		850,000		1,225,000
Imtech (Netherlands)		1,041,000		1,093,050
Interline Brands		2,000,000		2,600,000
M/I Homes		484,000		584,000
MOOG		1,520,000		1,660,000
Neopost (France)		0		114,000
Novozymes (Denmark)		255,000		363,000
NVR		0		60,000
OLAM International (Singapore)		15,200,000		30,000,000
Pall		1,375,000		1,675,000
Ritchie Brothers Auctioneers		200,000		437,500
Serco (United Kingdom)		607,259		3,000,000
Sociedad Quimica y Minera de Chile - ADR (Chile)		1,800,000		2,000,000
Consumer Goods & Services
American Apparel		0		830,444
Avis Budget Group		0		6,000,000
Bebe Stores		0		445,700
Charlotte Russe		0		1,706,102

	Number of Shares
	03/31/09		06/30/09
Charming Shoppes		0		2,751,621
Chico's FAS		2,850,000		7,507,000
Children's Place Retail Stores		200,000		1,061,000
Herman Miller		3,000,000		3,500,000
Hertz		0		3,000,000
Hibbett Sports		264,835		600,000
HNI		975,000		1,245,000
Hot Topic		1,987,000		3,308,890
Interface		0		646,780
J Crew Group		800,000		1,964,000
Knoll		3,300,000		4,000,000
Lifestyle International (Hong Kong)		0		3,381,400
Lululemon Athletica		0		1,800,000
New Oriental Education & Technology - ADR (China)		0		386,000
Princeton Review		2,800,000		2,974,300
Saks		0		3,100,000
Steelcase		0		2,016,856
True Religion Apparel		1,150,000		1,783,000
Urban Outfitters		3,950,000		4,020,000
Winnebago		570,000		850,000
Finance
Berkshire Hills Bancorp		100,000		234,693
CIT Group		0		7,000,000
Cullen/Frost Bankers		0		250,000
GATX		1,330,000		1,730,000
Investment Technology Group		647,502		700,000
McGrath Rentcorp		2,090,000		2,266,361
Sandy Spring Bancorp		0		178,550
TCF Financial		3,550,000		4,150,000
ViewPoint Financial		15,090		500,000
Wilmington Trust		0		1,690,000
Health Care
Alexion Pharmaceuticals		2,850,000		3,000,000
American Medical Systems		2,020,200		2,400,000
Beckman Coulter		0		300,000
Cepheid		3,100,000		4,000,000
Luminex		1,142,100		2,453,000
Medarex		4,300,000		4,800,000
NPS Pharmaceuticals		0		669,465

See accompanying notes to financial statements.

	Number of Shares
	03/31/09		06/30/09
Purchases (continued)
Energy & Minerals
Carrizo Oil & Gas		1,200,000		1,400,000
Fugro (Netherlands)		2,665,488		2,809,568
Gran Tierra Energy (Canada)		0		4,000,000
Royal Gold		0		300,000
ShawCor (Canada)		1,070,000		1,670,000
Silver Wheaton (Canada)		1,000,000		2,700,000
Tetra Technologies		1,038,000		1,198,000
Trinidad Drilling (Canada)		0		4,870,800
Other Industries
Ascendas Real Estate Investment Trust (Singapore)		0		13,069,100
Corporate Office Properties		715,000		900,000
DCT Industrial Trust		0		3,750,000
JB Hunt Transport Services		2,000,000		2,110,000
Kite Realty Group		1,900,000		2,300,000
Macerich Company		635,000		1,065,000
Red Electrica de Espana (Spain)		0		536,000
Washington Real Estate Investment Trust		0		700,000
World Fuel Services		0		200,000

	Number of Shares
	03/31/09		06/30/09
Sales
Information
Activision Blizzard		300,000		0
American Tower		2,250,000		1,750,000
Avnet		3,465,000		3,125,000
Concur Technologies		2,000,000		1,800,000
Discovery Communications		2,250,000		1,820,000
Flir Systems		5,000,000		3,276,660
Hexagon (Sweden)		6,100,000		5,200,000
Mediacom Communications		4,000,000		3,655,915
Red Hat		3,000,000		2,000,000
Rofin-Sinar Technologies		470,000		320,000
Rogers		280,000		0
SES (France)		1,250,000		893,000
Tellabs		2,800,000		0
Teradata		1,615,000		340,000
Trimble Navigation		2,840,000		2,490,000
Varian		540,897		500,000
Viad		124,674		0
Industrial Goods & Services
Administaff		2,025,000		1,935,000
American Commercial Lines		400,000		0
Aptargroup		500,000		350,000
Expeditors International of Washington		5,300,000		4,200,000
Martin Marietta Materials		850,000		700,000
Oshkosh		3,500,000		3,150,000
Pentair		2,600,000		2,300,000
TrueBlue		1,200,000		800,000
Union Tool (Japan)		130,700		0
Waste Connections		1,850,000		1,200,000
WW Grainger		1,200,000		1,000,000
Consumer Goods & Services
Abercrombie & Fitch		2,625,000		2,505,000
Coach		6,730,000		5,930,000
Expedia		5,000,000		4,700,000
GameStop		1,450,000		647,000
Intralot (Greece)		2,380,000		0
ITT Educational Services		1,442,303		1,400,000
Macy's		1,950,000		0
Nordstrom		1,200,000		0
Vail Resorts		2,265,690		1,950,000
Finance
Affiliated Managers Group		230,000		0
Cohen & Steers		1,150,000		550,000
People's United		12,063,899		8,563,899

See accompanying notes to financial statements.

Columbia Acorn Fund

Major Portfolio Changes in the Second Quarter (Unaudited), continued

	Number of Shares
	03/31/09		06/30/09
Sales (continued)
Health Care
Array Biopharma		1,509,185		0
Cephalon		1,115,000		1,000,000
Edwards Lifesciences		1,000,000		750,000
Hologic		2,800,000		1,900,000
ICU Medical		1,250,000		850,000
Kinetic Concepts		1,300,000		900,000
Lincare Holdings		1,150,000		0
Meridian Biosciences		790,000		0
Nektar Therapeutics		5,325,000		4,631,195
Rhoen-Klinikum (Germany)		1,650,000		975,300
Savient Pharmaceuticals		3,000,000		2,000,000
Seattle Genetics		4,400,000		3,834,516
Energy & Minerals
Exterran Holdings		1,055,000		502,000
Ultra Petroleum		1,300,000		975,000
Other Industries
General Growth Properties		2,200,000		0
Jiangsu Expressway (China)		34,804,000		0

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 97.3%
Information 24.7%
		> Business Software 4.8%
	6,700,000	Informatica (a)(b)	$	115,173
		Enterprise Data Integration Software
	1,150,000	Quality Systems (c)		65,504
		IT Systems for Medical Groups & Ambulatory Care Centers
	2,480,544	Micros Systems (a)		62,808
		Information Systems for Restaurants & Hotels
	12,500,000	Novell (a)		56,625
		Directory, Operating System & Identity Management Software
	1,800,000	Concur Technologies (a)		55,944
		Web Enabled Cost & Expense Management Software
	1,525,000	ANSYS (a)		47,519
		Simulation Software for Engineers & Designers
	2,000,000	Red Hat (a)		40,260
		Maintenance & Support for Open Source & Middleware
	2,425,000	Kenexa (a)(b)		28,057
		Recruiting & Workforce Management Solutions
	1,800,000	Blackbaud		27,990
		Software & Services for Non-profits
	3,050,000	Radiant Systems (a)(b)		25,315
		IT Systems for Restaurants, Convenience Stores & Retail Stores
	2,785,803	Actuate (a)(b)		13,316
		Information Delivery Software & Solutions
	1,000,000	NetSuite (a)(c)		11,810
		End to End IT Systems Solution Delivered Over the Web
	700,000	Avid Technology (a)		9,387
		Digital Nonlinear Editing Software & Systems
	885,000	Art Technology Group (a)		3,363
		Software & Tools to Optimize Websites for E-Commerce
				563,071
		> Instrumentation 3.3%
	1,385,000	Mettler Toledo (a)		106,853
		Laboratory Equipment
	3,276,660	FLIR Systems (a)		73,921
		Infrared Cameras
	2,490,000	Trimble Navigation (a)		48,879
		GPS-based Instruments
	5,200,000	Hexagon (Sweden)		47,045
		Measurement Equipment
	500,000	Dionex (a)		30,515
		Ion & Liquid Chromatography
	2,750,000	IPG Photonics (a)(b)		30,167
		Fiber Lasers
	500,000	Varian (a)		19,715
		Analytical Instruments
	1,053,965	FARO Technologies (a)(b)		16,368
		Precision Measurement Equipment
	400,000	Hamamatsu Photonics (Japan)		7,625
		Optical Sensors for Medical & Industrial Applications

Number of Shares			Value (000)
	320,000	Rofin-Sinar Technologies (a)	$	6,403
		Laser Systems
				387,491
		> Computer Hardware & Related Equipment 2.8%
	3,800,000	Amphenol		120,232
		Electronic Connectors
	2,400,000	II-VI (a)(b)		53,208
		Laser Optics & Specialty Materials
	1,340,000	Dolby Laboratories (a)		49,955
		Audio Technology for Consumer Electronics
	1,400,000	Zebra Technologies (a)		33,124
		Bar Code Printers
	800,000	Nice Systems - ADR (Israel) (a)		18,456
		Audio & Video Recording Solutions
	970,000	Netgear (a)		13,978
		Networking Products for Small Business & Home
	740,000	Belden CDT		12,358
		Specialty Cable
	944,100	Stratasys (a)		10,376
		Rapid Prototyping Systems
	340,000	Teradata (a)		7,966
		Enterprise Data Warehouse Systems
	500,000	Intermec (a)		6,450
		Bar Code & Wireless LAN Systems
				326,103
		> Mobile Communications 2.2%
	6,575,000	Crown Castle International (a)		157,931
		Communications Towers
	1,750,000	American Tower (a)		55,178
		Communications Towers in USA & Latin America
	1,000,000	SBA Communications (a)		24,540
		Communications Towers
	1,200,000	MetroPCS Communications (a)		15,972
		Discount Cellular Telephone Services
	1,500,000	Globalstar (a)		1,575
		Satellite Mobile Voice & Data Carrier
				255,196
		> Financial Processors 1.6%
	2,919,000	Global Payments		109,346
		Credit Card Processor
	10,000,000	Singapore Exchange (Singapore)		48,855
		Singapore Equity & Derivatives Market Operator
	2,125,000	Hong Kong Exchanges and Clearing (Hong Kong)		32,995
		Hong Kong Equity & Derivatives Market Operator
				191,196
		> Telephone and Data Services 1.5%
	9,500,000	tw telecom (a)(b)		97,565
		Fiber Optic Telephone/Data Services
	4,300,000	Cogent Communications (a)(b)		35,045
		Internet Data Pipelines

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Telephone and Data Services—continued
	8,165,000	PAETEC Holding (a)(b)	$	22,045
		Telephone/Data Services for Business
	2,000,000	General Communications (a)		13,860
		CATV, Web, Phone & Commercial Communications Provider in Alaska
	100,000	AboveNet (a)		8,098
		Metropolitan Fiber Communications Services
				176,613
		> CATV 1.5%
	2,250,000	Discovery Communications, Series C (a)		46,192
	1,820,000	Discovery Communications (a)		41,041
		CATV Programming
	57,000	Jupiter Telecommunications (Japan)		43,215
		Largest Cable Service Provider in Japan
	1,250,000	Liberty Global, Series C (a)		19,763
		CATV Franchises Outside the USA
	3,655,915	Mediacom Communications (a)(b)		18,682
		CATV Franchises
				168,893
		> Semiconductors & Related Equipment 1.4%
	1,035,000	Supertex (a)(b)		25,989
		Analog/Mixed-signal Semiconductors
	1,830,000	Microsemi (a)		25,254
		Analog/Mixed-signal Semiconductors
	3,384,000	ON Semiconductor (a)		23,214
		Mixed-signal & Power Management Semiconductors
	2,135,000	IXYS (b)		21,606
		Power Semiconductors
	1,765,000	Pericom Semiconductor (a)(b)		14,861
		Interface Integrated Circuits (ICs) & Frequency Control Products
	645,000	Monolithic Power Systems (a)		14,455
		High Performance Analog & Mixed Signal Integrated Circuits (ICs)
	2,110,000	Integrated Device Technology (a)		12,744
		Communications Semiconductors
	3,750,000	Entegris (a)		10,200
		Semiconductor Materials Management Products
	500,000	Littelfuse (a)		9,980
		Little Fuses
				158,303
		> Gaming Equipment & Services 1.2%
	4,025,000	Bally Technologies (a)(b)		120,428
		Slot Machines & Software
	1,000,000	Scientific Games (a)		15,770
		Lottery Services Provider
				136,198
		> Internet Related 0.9%
	2,500,000	Switch & Data Facilities (a)(b)		29,325
		Network Neutral Data Centers
	188,000	NHN (South Korea) (a)		25,977
		South Korea's Largest Online Search Engine

Number of Shares			Value (000)
	350,000	Equinix (a)	$	25,459
		Network Neutral Data Centers
	800,000	Akamai (a)		15,344
		Content Delivery Network (CDN) for Better Delivery of Online Content
	590,000	Vasco Data Security International (a)		4,313
		Online Banking Security & Enterprise Network Security
	1,000,000	TheStreet.com		2,090
		Financial Information Websites
				102,508
		> Computer Services 0.8%
	5,000,000	iGate (b)		33,100
		IT & Business Process Outsourcing Services
	1,520,000	SRA International (a)		26,691
		Government IT Services
	1,450,000	Virtusa (a)(b)		11,644
		Offshore IT Outsourcing
	4,500,000	Hackett Group (a)(b)		10,485
		IT Integration & Best Practice Research
	225,000	ManTech International (a)		9,684
		Government IT Services
	709,260	WNS - ADR (India) (a)		6,298
		Offshore BPO (Business Process Outsourcing) Services
				97,902
		> Telecommunications Equipment 0.7%
	1,085,000	CommScope (a)		28,492
		Wireless Infrastructure Equipment & Telecom Cable
	1,380,000	Polycom (a)		27,973
		Video Conferencing Equipment
	665,000	F5 Networks (a)		23,002
		Internet Traffic Management Equipment
	400,576	Blue Coat Systems (a)		6,626
		WAN Acceleration & Network Security
				86,093
		> Business Information & Marketing Services 0.6%
	2,500,000	Navigant Consulting (a)(b)		32,300
		Financial Consulting Firm
	540,000	FTI Consulting (a)		27,389
		Financial Consulting Firm
	1,240,000	InfoGROUP (a)		7,080
		Business Data for Sales Leads
				66,769
		> Electronics Distribution 0.6%
	3,125,000	Avnet (a)		65,719
		Electronic Components Distribution
				65,719
		> Contract Manufacturing 0.3%
	1,275,000	Plexus (a)		26,086
		Electronic Manufacturing Services
	18,300,000	Sanmina-SCI (a)		8,052
		Electronic Manufacturing Services
				34,138

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Satellite Broadcasting & Services 0.2%
	893,000	SES (France)	$	17,049
		Satellite Broadcasting Services
	250,000	Eutelsat (France)		6,459
		Co-leader in European Fixed Satellite Services
				23,508
		> Consumer Software 0.2%
	3,200,000	THQ (a)		22,912
		Entertainment Software
				22,912
		> Advertising 0.1%
	2,700,000	VisionChina Media - ADR (China) (a)		16,497
		Advertising on Digital Screens in China's Mass Transit System
				16,497
		> Radio —%
	1,541,000	Salem Communications (a)(b)		1,479
		Radio Stations for Religious Programming
	164,991	Saga Communications (a)		850
		Radio Stations in Small & Mid-sized Cities
	2,400,000	Spanish Broadcasting System (a)(b)		432
		Spanish Language Radio Stations
				2,761
		> TV Broadcasting —%
	2,500,000	Entravision Communications (a)		1,200
		Spanish Language TV & Radio Stations
	1,750,000	Gray Television		858
		Mid-market Affiliated TV Stations
				2,058
Information: Total				2,883,929
Industrial Goods & Services 19.4%
		> Machinery 7.8%
	4,500,000	Ametek		155,610
		Aerospace/Industrial Instruments
	4,200,000	Donaldson (b)		145,488
		Industrial Air Filtration
	2,200,000	ESCO Technologies (a)(b)		98,560
		Automatic Electric Meter Readers
	3,000,000	Clarcor (b)		87,570
		Mobile & Industrial Filters
	2,300,000	Pentair		58,926
		Pumps & Water Treatment
	1,975,000	Mine Safety Appliances (b)		47,597
		Safety Equipment
	3,150,000	Oshkosh		45,801
		Specialty Truck Manufacturer
	1,675,000	Pall		44,488
		Filtration & Fluids Clarification
	1,660,000	MOOG (a)		42,845
		Motion Control Products for Aerospace, Defense & Industrial Markets
	1,100,000	Nordson		42,526
		Dispensing Systems for Adhesives & Coatings
	1,300,000	Kaydon		42,328
		Specialized Friction & Motion Control Products

Number of Shares			Value (000)
	1,350,000	Toro	$	40,365
		Turf Maintenance Equipment
	1,225,000	HEICO (b)		35,844
		FAA Approved Aircraft Replacement Parts
	350,000	Lincoln Electric		12,614
		Welding Equipment & Consumables
	114,000	Neopost (France)		10,251
		Postage Meter Machines
	225,000	FreightCar America		3,782
		Coal Railcar Producer
				914,595
		> Industrial Materials & Specialty Chemicals 2.6%
	2,000,000	Sociedad Quimica y Minera de Chile - ADR (Chile)		72,380
		Producer of Specialty Fertilizers, Lithium & Iodine
	1,530,000	Albemarle		39,122
		Refinery Catalysts & Other Specialty Chemicals
	2,200,000	Nalco Holding Company		37,048
		Provider of Water Treatment & Process Chemicals & Services
	363,000	Novozymes (Denmark)		29,504
		Industrial Enzymes
	600,000	Greif		26,532
		Industrial Packaging
	1,600,000	Drew Industries (a)(b)		19,472
		RV & Manufactured Home Components
	15,000	Sika (Switzerland)		16,651
		Chemicals for Construction & Industrial Applications
	2,000,000	Kansai Paint (Japan)		14,319
		Paint Producer in Japan, India, China & Southeast Asia
	515,380	Carbone Lorraine (France)		14,166
		Advanced Industrial Materials
	350,000	Aptargroup		11,819
		Dispensing Systems for Consumer Products & Pharmaceuticals
	450,000	Celanese		10,688
		Commodity & Specialty Chemicals Provider
	350,000	Koppers Holdings		9,230
		Integrated Provider of Carbon Compounds
	743,100	Albany International		8,456
		Paper Machine Clothing & Advanced Textiles
				309,387
		> Other Industrial Services 2.4%
	4,200,000	Expeditors International of Washington		140,028
		International Freight Forwarder
	1,650,000	Forward Air (b)		35,178
		Freight Transportation Between Airports
	1,750,000	Mobile Mini (a)		25,672
		Portable Storage Units Leasing
	2,100,000	UTI Worldwide (a)		23,940
		Freight Forwarding & Logistics
	1,093,050	Imtech (Netherlands)		21,275
		Engineering & Technical Services
	600,000	Intertek Group (United Kingdom)		10,345
		Testing, Inspection & Certification Services

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Other Industrial Services—continued
	900,000	American Reprographics (a)	$	7,488
		Document Management & Logistics
	800,000	TrueBlue (a)		6,720
		Temporary Manual Labor
	615,000	TAL International Group		6,704
		Intermodal Freight Containers Leasing
				277,350
		> Industrial Distribution 2.2%
	2,275,000	Airgas		92,206
		Industrial Gas Distributor
	1,000,000	WW Grainger		81,880
		Industrial Distribution
	900,000	Watsco		44,037
		HVAC Distribution
	2,600,000	Interline Brands (a)(b)		35,568
		Industrial Distribution
				253,691
		> Outsourcing Services 1.5%
	2,300,000	Quanta Services (a)		53,199
		Electrical & Telecom Construction Services
	30,000,000	OLAM International (Singapore)		50,161
		Agriculture Supply Chain Manager
	1,935,000	Administaff (b)		45,027
		Professional Employer Organization
	3,000,000	Serco (United Kingdom)		20,843
		Facilities Management
	600,000	GP Strategies (a)		3,534
		Training Programs
				172,764
		> Construction 1.2%
	700,000	Martin Marietta Materials		55,216
		Aggregates
	1,700,000	Simpson Manufacturing		36,754
		Wall Joint Maker
	60,000	NVR (a)		30,144
		DC Homebuilder
	437,500	Ritchie Brothers Auctioneers (c)		10,259
		Heavy Equipment Auctioneer
	584,000	M/I Homes (a)		5,717
		Columbus-based Home Builder
				138,090
		> Waste Management 0.7%
	1,858,500	Republic Services		45,366
		Solid Waste Management
	1,200,000	Waste Connections (a)		31,092
		Solid Waste Management
				76,458
		> Electrical Components 0.4%
	1,300,000	Acuity Brands		36,465
		Commercial Lighting Fixtures
	1,000,000	Ushio (Japan)		15,947
		Industrial Light Sources
				52,412

Number of Shares			Value (000)
		> Conglomerates 0.3%
	2,869,585	Aalberts Industries (Netherlands)	$	22,578
		Flow Control & Heat Treatment
	600,000	Ibiden (Japan)		16,761
		Electronic Parts & Ceramics
				39,339
		> Steel 0.3%
	1,700,000	GrafTech International (a)		19,227
		Industrial Graphite Materials Producer
	390,000	Haynes International (a)		9,243
		Producer of High Performance Alloys
	450,000	Commercial Metals		7,214
		Vertically Integrated Steelmaker
				35,684
Industrial Goods & Services: Total				2,269,770
Consumer Goods & Services 16.1%
		> Retail 3.9%
	4,020,000	Urban Outfitters (a)		83,897
		Apparel & Home Specialty Retailer
	7,507,000	Chico's FAS (a)		73,043
		Women's Specialty Retailer
	2,505,000	Abercrombie & Fitch		63,602
		Teen Apparel Retailer
	1,964,000	J Crew Group (a)		53,067
		Multi-channel Branded Retailer
	1,061,000	Children's Place Retail Stores (a)		28,042
		Specialty Children's Retailer
	3,308,890	Hot Topic (a)(b)		24,188
		Music Inspired Retailer of Apparel, Accessories & Gifts
	1,800,000	Lululemon Athletica (a)(c)		23,454
		Premium Active Apparel Retailer
	4,250,000	Talbots (b)		22,950
		Women's Specialty Retailer
	1,706,102	Charlotte Russe (a)(b)		21,975
		Value Fashion Retailer
	647,000	GameStop (a)		14,241
		Video Game Specialty Retailer
	3,100,000	Saks (a)		13,733
		Luxury Department Store Retailer
	600,000	Hibbett Sports (a)		10,800
		Sporting Goods Retailer
	2,751,621	Charming Shoppes (a)		10,236
		Women's Specialty Plus Size Apparel Retailer
	1,371,366	Gaiam (a)(b)		7,501
		Healthy Living Catalogs & E-Commerce
	445,700	Bebe Stores		3,067
		Women's Contemporary Specialty Apparel Retailer
	830,444	American Apparel (a)		3,023
		Vertically Integrated Apparel Retailer
				456,819

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Educational Services 2.8%
	1,400,000	ITT Educational Services (a)	$	140,924
		Post-secondary Degree Services
	9,500,000	SkillSoft - ADR (a)(b)		74,100
		Web-based Learning Solutions (E-Learning)
	1,700,000	Career Education (a)		42,313
		Post-secondary Education
	1,750,301	Universal Technical Institute (a)(b)		26,132
		Vocational Training
	386,000	New Oriental Education & Technology - ADR (China) (a)		26,001
		China's Largest Private Education Service Provider
	2,974,300	Princeton Review (a)(b)		16,091
		College Preparation Courses
	2,000,000	Voyager Learning (a)(b)		6,900
		Education Services for the K-12 Market
				332,461
		> Travel 2.4%
	4,700,000	Expedia (a)		71,017
		Online Travel Services Company
	1,950,000	Vail Resorts (a)(b)		52,299
		Ski Resort Operator & Developer
	3,700,000	Gaylord Entertainment (a)(b)		47,027
		Convention Hotels
	1,700,000	Choice Hotels		45,237
		Franchisor of Budget Hotel Brands
	6,000,000	Avis Budget Group (a)(b)		33,900
		Second Largest Car Rental Company
	3,000,000	Hertz (a)		23,970
		Largest U.S. Rental Car Operator
	110,000	Pierre & Vacances (France)		7,653
		Vacation Apartment Lets
				281,103
		> Apparel 1.7%
	5,930,000	Coach		159,398
		Designer & Retailer of Branded Leather Accessories
	1,783,000	True Religion Apparel (a)(b)		39,761
		Premium Denim
				199,159
		> Nondurables 1.4%
	1,010,000	Chattem (a)(b)		68,781
		Personal Care Products
	2,500,000	Jarden (a)		46,875
		Branded Household Products
	1,700,000	Helen of Troy (a)(b)		28,543
		Hair Dryers & Curling Irons
	450,000	Energizer Holdings (a)		23,508
		Household & Personal Care Products
				167,707
		> Furniture & Textiles 1.1%
	3,500,000	Herman Miller (b)		53,690
		Office Furniture
	4,000,000	Knoll (b)		30,320
		Office Furniture
	1,245,000	HNI		22,485
		Office Furniture & Fireplaces

Number of Shares			Value (000)
	2,016,856	Steelcase	$	11,738
		Office Furniture
	646,780	Interface		4,010
		Modular & Broadloom Carpet
				122,243
		> Food & Beverage 0.6%
	1,600,000	Hansen Natural (a)		49,312
		Alternative Beverages
	2,500,000	Smart Balance (a)		17,025
		Healthy Food Products
				66,337
		> Casinos & Gaming 0.5%
	4,050,000	Pinnacle Entertainment (a)(b)		37,625
		Regional Casino Operator
	875,000	Penn National Gaming (a)		25,471
		Regional Casino Operator
				63,096
		> Leisure Products 0.4%
	1,390,000	Thor Industries		25,534
		RV & Bus Manufacturer
	1,416,000	Speedway Motorsports		19,484
		Motorsports Racetrack Owner & Operator
	850,000	Winnebago Industries		6,316
		Motor Home Maker
				51,334
		> Consumer Goods Distribution 0.4%
	2,600,000	Pool (b)		43,056
		Distributor of Swimming Pool Supplies & Equipment
	110,010	Central European Distribution (Poland) (a)		2,923
		Vodka Production & Spirits Distribution
				45,979
		> Other Consumer Services 0.4%
	1,900,000	Lifetime Fitness (a)(c)		38,019
		Sport & Fitness Club Operator
	3,381,400	Lifestyle International (Hong Kong)		4,397
		Mid to High-end Department Store Operator in Hong Kong & China
				42,416
		> Restaurants 0.3%
	550,000	P.F. Chang's China Bistro (a)		17,633
		Mandarin Style Restaurants
	2,000,000	AFC Enterprises (a)(b)		13,500
		Popeye's Restaurants
				31,133
		> Other Entertainment 0.2%
	435,000	CTS Eventim (Germany)		17,620
		Event Ticket Sales
				17,620
		> Other Durable Goods —%
	4,500,000	Champion Enterprises (a)(b)		1,440
		Manufactured Homes
				1,440
Consumer Goods & Services: Total				1,878,847

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
Finance 13.0%
		> Insurance 3.4%
	2,400,000	Assurant	$	57,816
		Specialty Insurance
	2,365,000	HCC Insurance Holdings		56,784
		Specialty Insurance
	1,300,000	Endurance Specialty Holdings		38,090
		Commercial Lines Insurance/Reinsurance
	1,748,000	Leucadia National (a)		36,865
		Insurance Holding Company
	1,450,000	Delphi Financial Group		28,174
		Workers Compensation & Group Employee Benefit Products & Services
	100,000	Markel (a)		28,170
		Specialty Insurance
	575,000	Navigators Group (a)		25,547
		Specialty Insurance
	1,000,000	Aspen Insurance		22,340
		Commercial Lines Insurance/Reinsurance
	9,420,000	Conseco (a)(b)		22,326
		Life, Long-term Care & Medical Supplement Insurance
	900,000	Tower Group		22,302
		Commercial & Personal Lines Insurance
	832,000	Willis Group		21,407
		Insurance Broker
	1,420,000	Selective Insurance Group		18,133
		Commercial & Personal Lines Insurance
	1,200,000	SeaBright Insurance Holdings (a)(b)		12,156
		Workers Compensation Insurance
	995,000	Protective Life		11,383
		Life Insurance
				401,493
		> Banks 3.3%
	3,000,000	BOK Financial		113,010
		Tulsa-based Southwest Bank
	4,150,000	TCF Financial		55,485
		Great Lakes Bank
	4,538,205	Valley National Bancorp		53,097
		New Jersey/New York Bank
	3,337,900	Associated Banc-Corp		41,724
		Midwest Bank
	1,160,000	SVB Financial Group (a)		31,575
		Bank to Venture Capitalists
	1,690,000	Wilmington Trust		23,085
		Delaware Trust Bank
	2,020,000	MB Financial (b)		20,584
		Chicago Bank
	1,200,000	TriCo Bancshares (b)		18,600
		California Central Valley Bank
	250,000	Cullen/Frost Bankers		11,530
		Texas Bank
	170,000	City National		6,261
		Bank & Asset Manager
	178,550	Sandy Spring Bancorp		2,625
		Baltimore, D.C. Bank
	1,000,000	West Coast Bancorp (b)		2,040
		Portland Community Bank

Number of Shares			Value (000)
	341,296	Green Bankshares	$	1,529
		Tennessee Bank
				381,145
		> Finance Companies 2.5%
	7,235,000	AmeriCredit (a)(b)(c)		98,034
		Auto Lending
	1,730,000	GATX		44,495
		Rail Car Lessor
	2,266,361	McGrath Rentcorp (b)		43,197
		Temporary Space & IT Rentals
	3,300,000	H&E Equipment Services (a)(b)		30,855
		Heavy Equipment Leasing
	1,545,000	World Acceptance (a)(b)		30,761
		Personal Loans
	655,000	Aaron's		19,532
		Rent to Own
	7,000,000	CIT Group		15,050
		Middle Market Lender, Equipment Leasing & Vendor Finance/Factoring
	1,650,000	CAI International (a)(b)		8,415
		International Container Leasing
	1,091,000	Marlin Business Services (a)(b)		6,110
		Small Equipment Leasing
				296,449
		> Brokerage & Money Management 2.1%
	6,448,000	SEI Investments		116,322
		Mutual Fund Administration & Investment Management
	4,235,000	Eaton Vance		113,286
		Specialty Mutual Funds
	700,000	Investment Technology Group (a)		14,273
		Electronic Trading
	550,000	Cohen & Steers (c)		8,223
		REIT Fund Manager
				252,104
		> Savings & Loans 1.7%
	8,563,899	People's United		128,801
		Connecticut Savings & Loan
	1,989,000	Washington Federal		25,857
		Savings & Loan
	450,000	Housing Development Finance (India)		22,075
		Indian Mortgage Lender
	500,000	ViewPoint Financial		7,615
		Texas Thrift
	660,000	Provident New York Bancorp		5,359
		New York State Thrift
	234,693	Berkshire Hills Bancorp		4,877
		Northeast Thrift
				194,584
Finance: Total				1,525,775
Health Care 11.7%
		> Medical Equipment & Devices 3.6%
	3,000,000	Alexion Pharmaceuticals (a)		123,360
		Biotech Focused on Orphan Diseases
	2,100,000	Illumina (a)		81,774
		Leading Tools & Service Provider for Genetic Analysis

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Medical Equipment & Devices—continued
	750,000	Edwards Lifesciences (a)	$	51,022
		Heart Valves
	700,000	Haemonetics (a)		39,900
		Blood & Plasma Collection Equipment
	2,400,000	American Medical Systems (a)		37,920
		Medical Devices to Treat Urological Conditions
	1,900,000	Hologic (a)		27,037
		Diagnostic & Medical Imaging Equipment for Women's Health
	900,000	Kinetic Concepts (a)		24,525
		Wound Healing & Tissue Repair Products
	300,000	Beckman Coulter		17,142
		In-vitro Clinical Diagnostics
	600,000	Orthofix International (a)		15,006
		Bone Fixation & Stimulation Devices
				417,686
		> Biotechnology & Drug Delivery 3.2%
	2,000,000	Myriad Genetics (a)		71,300
		Genetic Diagnostics
	1,660,000	Auxilium Pharmaceuticals (a)		52,091
		Biotech Focused on Niche Disease Areas
	3,000,000	BioMarin (a)		46,830
		Biotech Focused on Orphan Diseases
	4,800,000	Medarex (a)		40,080
		Humanized Antibodies
	3,834,516	Seattle Genetics (a)		37,271
		Antibody-based Therapies for Cancer
	400,000	United Therapeutics (a)		33,332
		Biotech Focused on Rare Diseases
	4,631,195	Nektar Therapeutics (a)(b)		30,010
		Drug Delivery Technologies
	2,000,000	Savient Pharmaceuticals (a)		27,720
		Biotech Company Focused on Niche Disease Areas
	1,781,707	InterMune (a)		27,082
		Drugs for Pulmonary Fibrosis & Hepatitis C
	669,465	NPS Pharmaceuticals (a)		3,119
		Orphan Drugs & Healthy Royalties
	97,275	Poniard (a)		581
		Cancer Biotech
	359,944	MicroDose Technologies (a)(d)		198
		Drug Inhaler Development
	1,249,999	Perlegen Sciences (a)(d)		25
		Large Scale Gene Sequencing
	187,500	Locus Pharmaceuticals, Series A-1, Pfd. (a)(d)		15
	96,644	Locus Pharmaceuticals, Series B-1, Pfd. (a)(d)		8
		High Throughput Rational Drug Design
				369,662
		> Medical Supplies 2.6%
	1,090,000	Henry Schein (a)		52,265
		Largest Distributor of Healthcare Products
	2,453,000	Luminex (a)(b)		45,479
		Life Science Tools & Molecular Diagnostics
	4,000,000	Cepheid (a)(b)		37,680
		Molecular Diagnostics

Number of Shares			Value (000)
	850,000	ICU Medical (a)(b)	$	34,978
		Intravenous Therapy Products
	1,675,000	QIAGEN (Netherlands) (a)		31,138
		Life Science Tools & Molecular Diagnostics
	486,000	Techne		31,012
		Cytokines, Antibodies & Other Reagents for Life Science
	665,000	Idexx Laboratories (a)		30,723
		Diagnostic Equipment & Services for Veterinarians
	700,000	Cooper		17,311
		Contact Lens Manufacturer
	900,000	Immucor (a)		12,384
		Automated Blood Typing Reagents
	150,000	Owens & Minor		6,573
		Distribution of Medical Supplies
				299,543
		> Health Care Services 1.8%
	2,200,000	Psychiatric Solutions (a)		50,028
		Behavioral Health Services
	1,050,000	Charles River Laboratories (a)		35,437
		Pharmaceutical Research
	1,847,035	PSS World Medical (a)		34,189
		Distributor of Medical Supplies
	700,000	MEDNAX (a)		29,491
		Physician Management for Pediatric & Anesthesia Practices
	4,250,000	eResearch Technology (a)(b)		26,393
		Clinical Research Services
	975,300	Rhoen-Klinikum (Germany)		21,566
		Health Care Services
	850,000	Healthcare Services Group		15,198
		Outsourced Services to Long-term Care Industry
				212,302
		> Pharmaceuticals 0.5%
	1,000,000	Cephalon (a)		56,650
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	2,450,000	United Drug (Ireland)		6,806
		Irish Pharmaceutical Wholesaler & Outsourcer
	151,531	Myriad Pharmaceuticals (a)		705
		Genetic Diagnostics
				64,161
Health Care: Total				1,363,354
Energy & Minerals 8.3%
		> Oil Services 3.9%
	2,809,568	Fugro (Netherlands)		116,666
		Sub-sea Oilfield Services
	3,100,000	FMC Technologies (a)		116,498
		Oil & Gas Wellhead Manufacturer
	3,200,000	Atwood Oceanics (a)		79,712
		Offshore Drilling Contractor
	1,000,000	Oceaneering International (a)		45,200
		Provider of Sub-sea Services & Manufactured Products
	1,670,000	ShawCor (Canada)		28,902
		Oil & Gas Pipeline Products

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Oil Services—continued
	4,870,800	Trinidad Drilling (Canada)	$	20,603
		Operator of Deep Land Drilling Rigs & Service Rigs throughout North America
	1,750,000	Tesco (a)		13,895
		Developing New Well Drilling Technologies
	375,000	Bristow (a)		11,111
		Largest Provider of Helicopter Services to Offshore Oil & Gas Producers
	1,198,000	Tetra Technologies (a)		9,536
		U.S.-based Service Company with Life of Field Approach
	502,000	Exterran Holdings (a)		8,052
		Natural Gas Compressor Rental & Fabrication
	2,983,500	Horizon North Logistics (Canada) (a)		2,693
		Provides Diversified Oil Service Offering in Northern Canada
				452,868
		> Oil & Gas Producers 3.8%
	3,600,000	Southwestern Energy (a)		139,860
		Oil & Gas Producer
	1,850,000	XTO Energy		70,559
		Oil & Gas Producer
	1,100,000	Range Resources		45,551
		Oil & Gas Producer
	5,110,550	Pacific Rubiales Energy (Canada) (a)		42,136
		Oil Production & Exploration in Colombia
	975,000	Ultra Petroleum (a)		38,025
		Oil & Gas Producer
	2,400,000	Tullow Oil (United Kingdom)		37,131
		Oil & Gas Producer
	1,400,000	Carrizo Oil & Gas (a)		24,010
		Oil & Gas Producer
	1,400,000	Denbury Resources (a)		20,622
		Oil Producer Using Co2 Injection
	4,000,000	Gran Tierra Energy (Canada) (a)		13,927
		Oil Exploration & Production in Colombia, Peru & Argentina
	1,200,000	TriStar Oil & Gas (Canada) (a)		11,338
		Canadian Oil & Gas Producer
	1,500,000	Vaalco Energy (a)		6,345
		Oil & Gas Producer
				449,504
		> Mining 0.5%
	2,700,000	Silver Wheaton (Canada) (a)		22,248
		Silver Mining Royalty Company
	7,725,000	Uranium One (South Africa) (a)		17,733
		Uranium Mines in Kazakhstan, the U.S. & Australia
	300,000	Royal Gold		12,510
		Precious Metals Mining Royalty Company
	1,000,000	Ivanhoe Mines (Canada) (a)		5,545
		Copper Mine Project in Mongolia
				58,036
		> Oil Refining, Marketing & Distribution 0.1%
	435,000	Oneok		12,828
		Natural Gas Distribution, Pipeline Processing & Trading
				12,828

Number of Shares			Value (000)
		> Alternative Energy —%
	1,800,000	Synthesis Energy Systems (China) (a)	$	2,070
		Owner/Operator of Gasification Plants
				2,070
Energy & Minerals: Total				975,306
Other Industries 4.1%
		> Real Estate 2.2%
	675,000	Federal Realty Investment Trust		34,776
		Shopping Centers
	850,000	Digital Realty Trust		30,473
		Technology-focused Office Buildings
	900,000	Corporate Office Properties		26,397
		Office Buildings
	900,000	American Campus Communities		19,962
		Student Housing
	1,065,000	Macerich Company (c)		18,755
		Regional Shopping Malls
	750,000	SL Green Realty		17,205
		Manhattan Office Buildings
	700,000	Washington REIT		15,659
		Washington D.C. Diversified Properties
	3,750,000	DCT Industrial Trust		15,300
		Industrial Properties
	40,000,000	Mapletree Logistics (Singapore)		15,263
		Asian Logistics Landlord
	13,069,100	Ascendas REIT (Singapore)		14,306
		Singapore Industrial Property Landlord
	1,360,000	BioMed Realty Trust		13,913
		Life Science-focused Office Buildings
	2,800	Orix JREIT (Japan)		12,817
		Diversified REIT
	1,400,000	Extra Space Storage		11,690
		Self Storage Facilities
	1,158,000	Forest City Enterprises, Class B (b)		7,515
		Commercial & Residential Property Developer
	2,300,000	Kite Realty Group		6,716
		Community Shopping Centers
	37,407	Security Capital European Realty (Luxembourg) (a)(d)(e)		—
		Self Storage Properties
				260,747
		> Transportation 1.3%
	2,110,000	JB Hunt Transport Services		64,418
		Truck & Intermodal Carrier
	2,480,000	Heartland Express		36,506
		Regional Trucker
	2,500,000	Rush Enterprises, Class A (a)(b)		29,125
	500,000	Rush Enterprises, Class B (a)(b)		4,955
		Truck Sales & Services
	625,000	American Commercial Lines (a)		9,675
		Operator of Inland Barges/Builder of Barges & Vessels
	200,000	World Fuel Services		8,246
		Global Fuel Broker
				152,925

See accompanying notes to financial statements.

Number of Shares or Principal Amount (000)			Value (000)
		> Regulated Utilities 0.6%
	1,800,000	Northeast Utilities	$	40,158
		Regulated Electric Utility
	536,000	Red Electrica de Espana (Spain)		24,251
		Spanish Power Grid
				64,409
Other Industries: Total				478,081
Total Equities: 97.3% (Cost: $10,546,278)				11,375,062
Securities Lending Collateral: 1.1%
	133,395,450	Dreyfus Government Cash Management Fund (f) (7 day yield of 0.150%)		133,395
Total Securities Lending Collateral: (Cost: $133,395)				133,395
Short-Term Obligations: 2.9%
		> Repurchase Agreement 2.5%
$	291,659	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.0001%, collateralized by U.S. Treasury obligations with various maturities to 8/17/17, market value $297,497 (repurchase proceeds $291,659)		291,659
				291,659
		> Commercial Paper 0.4%
	50,000	Toyota Motor Credit 0.26% due 7/06/09		49,998
				49,998
Total Short-Term Obligations: (Amortized Cost: $341,657)				341,657
Total Investments: 101.3% (Cost: $11,021,330)(g)(h)				11,850,114
Obligation to Return Collateral for Securities Loaned: (1.1)%				(133,395	)
Cash and Other Assets Less Liabilities: (0.2)%				(22,925	)
Total Net Assets: 100.0%			$	11,693,794

ADR = American Depositary Receipts.

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

> Notes to Statement of Investments (dollar values in thousands)

(a) Non-income producing security.

(b) An affiliated person of the Fund may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in these affiliated companies during the six months ended June 30, 2009, are as follows:

Affiliates	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 6/30/09		Value		Dividend
Actuate		1,683,760		1,102,043		-		2,785,803	$	13,316	$	-
Administaff		2,025,000		-		90,000		1,935,000		45,027		527
AFC Enterprises		1,800,000		200,000		-		2,000,000		13,500		-
AmeriCredit		7,235,000		-		-		7,235,000		98,034		-
Array Biopharma*		2,910,000		-		2,910,000		-		-		-
Avis Budget Group		-		6,000,000		-		6,000,000		33,900		-
Bally Technologies		3,750,000		275,000		-		4,025,000		120,428		-
CAI International		1,500,000		150,000		-		1,650,000		8,415		-
Carrizo Oil & Gas*		2,525,000		200,000		1,325,000		1,400,000		24,010		-
Cepheid		3,100,000		900,000		-		4,000,000		37,680		-
Champion Enterprises		4,500,000		-		-		4,500,000		1,440		-
Charlotte Russe		-		1,706,102		-		1,706,102		21,975		-
Chattem		1,010,000		-		-		1,010,000		68,781		-
Clarcor		3,000,000		-		-		3,000,000		87,570		540
Cogent Communications		4,300,000		-		-		4,300,000		35,045		-
Conseco		9,420,000		-		-		9,420,000		22,326		-
Donaldson		4,200,000		-		-		4,200,000		145,488		966
Drew Industries		1,324,000		276,000		-		1,600,000		19,472		-
Entravision Communications*		2,500,000		-		-		2,500,000		1,200		-
eResearch Technology		3,935,901		314,099		-		4,250,000		26,393		-
ESCO Technologies		2,200,000		-		-		2,200,000		98,560		-
FARO Technologies		1,275,000		-		221,035		1,053,965		16,368		-
Forest City Enterprises, Class B		1,158,000		-		-		1,158,000		7,515		-
Forward Air		1,900,000		-		250,000		1,650,000		35,178		231
Gaiam		1,200,000		171,366		-		1,371,366		7,501		-
Gaylord Entertainment		3,300,000		400,000		-		3,700,000		47,027		-
H&E Equipment Services		3,300,000		-		-		3,300,000		30,855		-
Hackett Group		4,600,000		-		100,000		4,500,000		10,485		-
HEICO		850,000		375,000		-		1,225,000		35,844		51
Helen of Troy		1,900,000		-		200,000		1,700,000		28,543		-
Herman Miller		3,000,000		500,000		-		3,500,000		53,690		528
Hot Topic		-		3,791,890		483,000		3,308,890		24,188		-
ICU Medical		1,250,000		-		400,000		850,000		34,978		-
iGate		5,000,000		-		-		5,000,000		33,100		550
II-VI		2,400,000		-		-		2,400,000		53,208		-
Informatica		5,500,000		1,200,000		-		6,700,000		115,173		-
Interline Brands		2,000,000		600,000		-		2,600,000		35,568		-
IPG Photonics		2,750,000		-		-		2,750,000		30,167		-
ITT Educational Services*		2,150,000		-		750,000		1,400,000		140,924		-
IXYS		2,035,000		100,000		-		2,135,000		21,606		-
Kenexa		2,425,000		-		-		2,425,000		28,057		-
Kite Realty Group*		1,900,000		400,000		-		2,300,000		6,716		740
Knoll		3,300,000		700,000		-		4,000,000		30,320		476
Luminex		1,110,000		1,343,000		-		2,453,000		45,479		-
Marlin Business Services		1,091,000		-		-		1,091,000		6,110		-
MB Financial		2,020,000		-		-		2,020,000		20,584		263
McGrath Rentcorp		1,890,000		376,361		-		2,266,361		43,197		838
Mediacom Communications		4,000,000		-		344,085		3,655,915		18,682		-
Mine Safety Appliances		1,975,000		-		-		1,975,000		47,597		948
Mobile Mini*		1,750,000		-		-		1,750,000		25,672		-
Navigant Consulting		2,500,000		-		-		2,500,000		32,300		-
Nektar Therapeutics		5,325,000		-		693,805		4,631,195		30,010		-
PAETEC Holdings		8,000,000		165,000		-		8,165,000		22,045		-
Pericom Semiconductor		915,000		850,000		-		1,765,000		14,861		-
Pinnacle Entertainment		4,050,000		-		-		4,050,000		37,625		-
Pool		2,600,000		-		-		2,600,000		43,056		676
Princeton Review		2,550,000		424,300		-		2,974,300		16,091		-
Quality Systems*		1,850,000		-		700,000		1,150,000		65,504		975

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

Affiliates	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 6/30/09		Value		Dividend
Radiant Systems		3,050,000		-		-		3,050,000	$	25,315	$	-
Rush Enterprises		2,750,000		250,000		-		3,000,000		34,080		-
Salem Communications		1,541,000		-		-		1,541,000		1,479		-
Savient Pharmaceuticals*		1,416,941		1,583,059		1,000,000		2,000,000		27,720		-
SeaBright Insurance Holdings		1,200,000		-		-		1,200,000		12,156		-
Seattle Genetics*		4,400,000		-		565,484		3,834,516		37,271		-
SkillSoft - ADR		9,500,000		-		-		9,500,000		74,100		-
Smart Balance*		5,000,000		-		2,500,000		2,500,000		17,025		-
Spanish Broadcasting System		2,400,000		-		-		2,400,000		432		-
Stewart Information Services*		909,420		-		909,420		-		-		-
Stratasys*		1,180,000		-		235,900		944,100		10,376		-
Supertex		1,035,000		-		-		1,035,000		25,989		-
Switch & Data Facilities		2,500,000		-		-		2,500,000		29,325		-
Talbots		4,250,000		-		-		4,250,000		22,950		-
TriCo Bancshares		1,200,000		-		-		1,200,000		18,600		312
True Religion Apparel		1,150,000		633,000		-		1,783,000		39,761		-
tw telecom		9,500,000		-		-		9,500,000		97,565		-
Universal Technical Institute		1,500,000		250,301		-		1,750,301		26,132		-
Vail Resorts		2,390,000		-		440,000		1,950,000		52,299		-
Viad*		1,032,075		-		1,032,075		-		-		73
Virtusa		1,000,000		450,000		-		1,450,000		11,644		-
Voyager Learning		2,000,000		-		-		2,000,000		6,900		-
West Coast Bancorp		837,000		163,000		-		1,000,000		2,040		18
World Acceptance		1,545,000		-		-		1,545,000		30,761		-
TOTAL OF AFFILIATED TRANSACTIONS		221,024,097		25,849,521		15,149,804		231,723,814	$	2,822,304	$	8,712

* At June 30, 2009, the Fund owned less than five percent of the company's outstanding voting shares.

The aggregate cost and value of these companies at June 30, 2009, were $3,111,124 and $2,822,304, respectively. Investments in affiliated companies represented 24.1% of the Fund's total net assets at June 30, 2009.

(c) All or a portion of this security was on loan at June 30, 2009. The total market value of securities on loan at June 30, 2009 was $129,784.

(d) Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued at their fair value determined in good faith under consistently applied procedures established by the board of trustees. At June 30, 2009, these securities amounted to $246, which represented less than 0.01% of total net assets.

Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
MicroDose Technologies	11/24/00		359,944	$	2,005	$	198
Perlegen Sciences	3/30/01		1,249,999		4,500		25
Locus Pharmaceuticals, Series A-1, Pfd.	9/05/01		187,500		7,500		15
Locus Pharmaceuticals, Series B-1, Pfd.	2/08/07		96,644		280		8
Security Capital European Realty	8/20/98-7/20/99		37,407		205		-
				$	14,490	$	246

(e) Security has no value.

(f) Investment made with cash collateral received from securities lending activity.

(g) At June 30, 2009, for federal income tax purposes cost of investments was $11,021,330 and net unrealized appreciation was $828,784 consisting of gross unrealized appreciation of $3,273,254 and gross unrealized depreciation of $2,444,470.

(h) On June 30, 2009, the market value of foreign securities represented 9.52% of total net assets. The Fund's foreign portfolio was diversified as follows:

	Value		Percentage of Net Assets
Netherlands	$	191,657		1.64
Canada		147,392		1.26
Singapore		128,585		1.10
Japan		110,684		0.95
Chile		72,380		0.62
United Kingdom		68,319		0.58
France		55,578		0.48
Sweden		47,045		0.40
China		44,568		0.38
Germany		39,186		0.34
Hong Kong		37,392		0.32
	Value		Percentage of Net Assets
Denmark	$	29,504		0.25
India		28,373		0.24
South Korea		25,977		0.22
Spain		24,251		0.21
Israel		18,456		0.16
South Africa		17,733		0.15
Switzerland		16,651		0.14
Ireland		6,806		0.06
Poland		2,923		0.02
Luxembourg		-		-
Total Foreign Portfolio	$	1,113,460		9.52

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

> Notes to Statement of Investments (dollar values in thousands)

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Equities
Total Information	$	2,654,709	$	229,220	$	-	$	2,883,929
Total Industrial Goods & Services		2,026,969		242,801		-		2,269,770
Total Consumer Goods & Services		1,802,150		29,670		-		1,831,820
Total Finance		1,503,700		22,075		-		1,525,775
Total Health Care		1,334,736		28,372		246		1,363,354
Total Energy & Minerals		821,509		153,797		-		975,306
Total Other Industries		458,471		66,637		-		525,108
Total Equities		10,602,244		772,572		246		11,375,062
Securities Lending Collateral		133,395		-		-		133,395
Short-Term Obligations		-		341,657		-		341,657
Total Investments		10,735,639		1,114,229		246		11,850,114
Total	$	10,735,639	$	1,114,229	$	246	$	11,850,114

The Fund's assets assigned to the Level 2 input category include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation.

The information in the below reconciliation represents fiscal year to date activity for any securities identified as using Level 3 inputs at either the beginning or the end of the current fiscal period.

Investments in Secruities	Balance as of December 31, 2008		Accrued Discounts/ Premiums		Realized Gain/(Loss)		Change in Unrealized Appreciation (Depreciation)			Net Purchases		Net Sales		Net transfers into Level 3		Net transfers out of Level 3		Balance as of June 30, 2009		Change in Unrealized Appreciation (Depreciation) from Investments held at June 30, 2009
Health Care
Biotechnology & Drug Delivery	$	426	$	-	$	-	$	(180	)	$	-	$	-	$	-	$	-	$	246	$	(180	)
Other Industries
Real Estate*		-		-		-		-			-		-		-		-		-		-
Total	$	426	$	-	$	-	$	(180	)	$	-	$	-	$	-	$	-	$	246	$	(180	)

* Security Capital European Realty has no value.

The change in unrealized depreciation attributable to securities owned at June 30, 2009 which were valued using significant unobservable inputs (Level 3) amounted to $180. This amount is included in net change in unrealized depreciation on the Statement of Changes in Net Assets.

For more information on valuation inputs, and their aggregation into the levels used in the tables above, please refer to the Security Valuation section in the accompanying Notes to Financial Statements.

See accompanying notes to financial statements.

Columbia Acorn International

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Asia
> Japan
Aeon Delight		1,066,100		1,243,900
Aeon Mall		880,000		1,354,000
Asics		1,748,100		2,143,500
Benesse		286,900		398,900
Daiseki		755,700		787,200
Point		418,760		519,570
Rohto Pharmaceutical		1,250,000		1,735,100
Zenrin		600,000		743,100
> China
Mindray - ADR		797,000		833,800
New Oriental Education & Technology - ADR		223,000		382,000
RexLot Holdings		151,000,000		250,000,000
Shandong Weigao		2,625,000		4,800,000
> Singapore
Ascendas REIT		0		9,821,100
Mapletree Logistics		70,000,000		76,413,000
OLAM International		27,500,000		30,000,000
Singapore Exchange		6,900,000		7,000,000
> India
Educomp Solutions		250,000		370,000
Shriram Transport Finance		1,600,000		2,135,000
> South Korea
Mirae Asset Securities		0		376,000
NHN		94,000		245,000
> Taiwan
President Chain Store		6,996,000		9,994,000
Simplo Technology		0		3,655,000
Yuanta FHC		0		45,000,000
> Hong Kong
Lifestyle International		19,000,000		20,668,600
Europe
> United Kingdom
Chemring		275,000		384,000
Cobham		3,050,000		4,434,000
N Brown Group		0		2,730,000
Serco		5,100,000		5,500,000
> Netherlands
Aalberts Industries		1,992,322		2,051,535
Fugro		628,000		661,945
Smit Internationale		228,993		244,969
Vopak		372,000		390,900
> Germany
Tognum		656,900		744,400

	Number of Shares
	03/31/09		06/30/09
> France
Carbone Lorraine		309,390		399,598
Eutelsat		0		393,000
Neopost		198,000		295,000
Pierre & Vacances		171,700		222,118
Rubis		139,900		155,900
SAFT		322,000		441,635
> Sweden
East Capital Explorer		0		750,000
> Italy
CIR		12,866,000		15,569,356
Credito Emiliano		1,500,000		2,045,000
> Denmark
Novozymes		130,000		297,000
> Spain
Red Electrica de Espana		440,000		532,000
Other Countries
> United States
Alexion Pharmaceuticals		350,000		475,000
Atwood Oceanics		1,290,000		1,340,000
Illumina		0		150,000
Ritchie Brothers Auctioneers		0		150,000
World Fuel Services		0		200,000
> Canada
CCL Industries		819,000		1,117,000
Ivanhoe Mines		0		744,000
> Australia
Cochlear		0		70,000
> South Africa
Naspers		1,723,000		1,973,000
Latin America
> Brazil
Localiza Rent A Car		5,156,000		5,500,000
Natura		1,500,000		2,000,000
> Mexico
Grupo Aeroportuario del Sureste - ADR		600,000		700,000

See accompanying notes to financial statements.

Columbia Acorn International

Major Portfolio Changes in the Second Quarter (Unaudited), continued

	Number of Shares
	03/31/09		06/30/09
Sales
Asia
> Japan
Jupiter Telecommunications		43,500		31,500
Makita		540,000		430,000
Cosel		882,000		0
NGK Insulators		690,000		0
Ryohin Keikaku		288,000		0
SYSMEX		231,000		0
T. Hasegawa		538,000		0
Union Tool		247,200		0
Yusen Air & Sea Service		614,400		0
> China
Jiangsu Expressway		28,896,000		20,563,000
Hopewell Highway Infrastructure		17,098,900		0
Sinotrans		34,508,800		0
> Singapore
ComfortDelGro		18,060,000		0
> India
United Phosphorus		8,900,000		3,449,517
> South Korea
Taewoong		360,000		298,000
Woongjin Coway		1,112,000		753,000
> Hong Kong
Hong Kong Exchanges and Clearing		3,000,000		2,700,000
Hong Kong Aircraft Engineering		709,100		0
Europe
> United Kingdom
Intermediate Capital		900,000		864,000
Randgold Resources - ADR		400,000		212,000
> Netherlands
Imtech		2,025,000		1,871,250
QIAGEN		850,000		650,000
> Germany
Rational		175,143		155,000
Rhoen-Klinikum		1,607,845		1,010,947
> France
Iliad		250,000		211,000
Norbert Dentressangle		216,215		160,701
SES		1,447,000		944,000
> Switzerland
Geberit		200,000		167,000
Kuehne & Nagel		317,000		275,000

	Number of Shares
	03/31/09		06/30/09
> Sweden
Hexagon		4,733,000		3,944,000
> Italy
Sabaf		115,295		0
> Poland
ING Bank Slaski		44,162		0
> Greece
Intralot		5,090,000		3,427,000
> Russia
Novolipetsk Steel - GDR		775,000		0
Other Countries
> United States
FMC Technologies		410,000		251,000
> South Africa
Impala Platinum Holdings		1,440,000		0
> New Zealand
Sky City Entertainment		6,320,612		868,418
Latin America
> Brazil
Porto Seguro		2,500,000		0
> Chile
Sociedad Quimica y Minera de Chile - ADR		1,129,000		862,000

See accompanying notes to financial statements.

Columbia Acorn International

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 94.4%
Asia 42.6%
		> Japan 18.4%
	6,550,000	Kansai Paint	$	46,895
		Paint Producer in Japan, India, China & Southeast Asia
	11,371	Nippon Residential Investment		27,963
		Residential REIT
	519,570	Point		27,895
		Apparel Specialty Retailer
	10,170	Seven Bank		26,592
		ATM Processing Services
	1,354,000	Aeon Mall		25,621
		Suburban Shopping Mall Developer, Owner & Operator
	3,000,000	Kamigumi		25,254
		Port Cargo Handling & Logistics
	31,500	Jupiter Telecommunications		23,882
		Largest Cable Service Provider in Japan
	4,300	Osaka Securities Exchange		20,490
		Osaka Securities Exchange
	1,243,900	Aeon Delight		20,095
		Facility Maintenance & Management
	1,735,100	Rohto Pharmaceutical		19,576
		Health & Beauty Products
	2,143,500	Asics		19,462
		Footwear & Apparel
	4,200	Orix JREIT		19,226
		Diversified REIT
	925,200	Glory		18,303
		Currency Handling Systems & Related Equipment
	640,000	Ibiden		17,878
		Electronic Parts & Ceramics
	737,000	Kintetsu World Express		17,504
		Airfreight Logistics
	787,200	Daiseki		17,284
		Waste Disposal & Recycling
	1,750,000	Suruga Bank		16,680
		Regional Bank
	553,400	Unicharm PetCare		16,520
		Pet Food & Pet Toiletries
	1,900	Nippon Building Fund		16,261
		Office REIT
	398,900	Benesse		15,943
		Education Service Provider
	950,000	Ushio		15,150
		Industrial Light Sources
	7,500	Wacom		15,135
		Computer Graphic Illustration Devices
	193,000	Nakanishi		14,187
		Dental Tools & Machinery
	3,050	Fukuoka		13,672
		Diversified REIT in Fukuoka
	643,000	Ain Pharmaciez (a)		13,332
		Dispensing Pharmacy/Drugstore Operator
	587,800	Miura		13,094
		Industrial Boiler

Number of Shares			Value (000)
	3,100,000	Chuo Mitsui Trust Holdings	$	11,765
		Trust Bank
	480,000	Olympus		11,279
		Medical Equipment (Endoscopes) & Cameras
	580,000	Hamamatsu Photonics		11,056
		Optical Sensors for Medical & Industrial Applications
	743,100	Zenrin		10,982
		Map Content Publisher
	785,000	Tamron		10,704
		Camera Lens Maker
	430,000	Makita		10,356
		Power Tools
	1,650	Nippon Accommodations Fund		7,405
		Residential REIT
	407,200	As One		7,290
		Scientific Supplies Distributor
	116,300	Toyo Tanso		4,433
		Carbon & Graphite Products for Industrial Use
	115,000	Tsumura		3,583
		Traditional Chinese/Japanese Herbal Rx Drugs (Kampo)
				612,747
		> China 5.7%
	29,166,400	China Green		30,605
		Chinese Fruit & Vegetable Grower & Processor
	382,000	New Oriental Education & Technology - ADR (b)		25,731
		China's Largest Private Education Service Provider
	833,800	Mindray - ADR		23,280
		Medical Device Manufacturer
	14,182,000	China Yurun Food		21,353
		Meat Processor in China
	250,000,000	RexLot Holdings (b)		19,661
		Lottery Equipment Supplier in China
	13,414,000	China Shipping Development		17,114
		China's Dominant Shipper for Oil & Coal
	20,563,000	Jiangsu Expressway		15,065
		Chinese Toll Road Operator
	15,300,000	Fu Ji Food & Catering Services		12,858
		Food Catering Service Provider in China
	4,800,000	Shandong Weigao		12,300
		Vertically Integrated Hospital Consumable Manufacturer
	1,000,000	VisionChina Media - ADR (b)		6,110
		Advertising on Digital Screens in China's Mass Transit System
	282,500	ZhongDe Waste Technology		5,130
		Solid Municipal Waste & Medical Waste Incinerator Manufacturer
				189,207
		> Singapore 4.2%
	30,000,000	OLAM International		50,161
		Agriculture Supply Chain Manager
	7,000,000	Singapore Exchange		34,199
		Singapore Equity & Derivatives Market Operator

See accompanying notes to financial statements.

Columbia Acorn International

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Singapore—continued
	76,413,000	Mapletree Logistics	$	29,157
		Asian Logistics Landlord
	30,000,000	CDL Hospitality Trust		17,112
		Hotel Owner/Operator
	9,821,100	Ascendas REIT		10,751
		Singapore Industrial Property Landlord
				141,380
		> India 4.2%
	370,000	Educomp Solutions (b)		29,044
		Multimedia Educational Content
	1,008,727	Asian Paints		24,675
		India's Largest Paint Company
	1,700,000	Jain Irrigation Systems		22,413
		Agricultural Micro-irrigation Systems & Food Processing
	450,000	Housing Development Finance (b)		22,075
		Indian Mortgage Lender
	1,350,000	Mundra Port & Special Economic		17,180
		Zone Indian West Coast Shipping Port
	2,135,000	Shriram Transport Finance		13,529
		Truck Financing in India
	3,449,517	United Phosphorus		10,350
		Off-patent Crop Protection Chemicals
				139,266
		> South Korea 3.9%
	245,000	NHN (b)		33,853
		South Korea's Largest Online Search Engine
	158,000	MegaStudy		28,440
		Online Education Service Provider
	298,000	Taewoong		20,955
		Niche Custom Forging
	376,000	Mirae Asset Securities		20,368
		South Korean Largest Diversified Financial Company
	753,000	Woongjin Coway		18,272
		South Korean Household Appliance Rental Service Provider
	616,000	Sung Kwang Bend		9,229
		Custom Industrial Pipes
				131,117
		> Taiwan 3.1%
	45,000,000	Yuanta FHC		30,107
		Financial Holding Company in Taiwan
	9,994,000	President Chain Store		25,580
		Taiwan's Number One Convenience Chain Store Operator
	1,322,000	Formosa International Hotels		18,475
		Hotel, Food & Beverage Operation & Hospitality Management Services
	5,844,793	Everlight Electronics		14,859
		LED Packager
	3,655,000	Simplo Technology		14,659
		World's Largest Notebook Battery Pack Supplier
				103,680

Number of Shares			Value (000)
		> Hong Kong 2.4%
	2,700,000	Hong Kong Exchanges and Clearing	$	41,924
		Hong Kong Equity & Derivatives Market Operator
	20,668,600	Lifestyle International		26,878
		Mid to High-end Department Store Operator in Hong Kong & China
	74,150,656	NagaCorp		9,788
		Casino/Entertainment Complex in Cambodia
				78,590
		> Indonesia 0.7%
	75,000,000	Perusahaan Gas Negara		23,051
		Gas Distributor & Pipeline Operator
				23,051
Asia: Total				1,419,038
Europe 34.7%
		> United Kingdom 7.0%
	5,500,000	Serco		38,212
		Facilities Management
	2,185,600	Intertek Group		37,684
		Testing, Inspection & Certification Services
	3,100,000	Capita Group		36,547
		White Collar, Back Office Outsourcing
	2,500,000	Smith & Nephew		18,534
		Medical Equipment & Supplies
	384,000	Chemring		13,727
		Defense Manufacturer of Countermeasures & Energetics
	1,000,000	Rotork		13,639
		Valve Actuators for Oil & Water Pipelines
	212,000	Randgold Resources - ADR		13,604
		Gold Mining in Western Africa
	4,000,000	RPS Group		13,190
		Environmental Consulting & Planning
	4,434,000	Cobham		12,647
		Aerospace Components
	690,000	Tullow Oil		10,675
		Oil & Gas Producer
	2,730,000	N Brown Group		9,664
		Home Shopping Women's Clothes Retailer
	1,000,000	Keller Group		9,115
		Ground Engineering
	864,000	Intermediate Capital		6,909
		European Provider of Mezzanine Capital
				234,147
		> Netherlands 6.0%
	1,871,250	Imtech		36,421
		Engineering & Technical Services
	1,372,989	Koninklijke TenCate (a)		33,254
		Advanced Textiles & Industrial Fabrics
	661,945	Fugro		27,487
		Sub-sea Oilfield Services
	1,385,000	Unit 4 Agresso (b)(a)		22,654
		Business Development Software
	390,900	Vopak (b)		19,553
		World's Largest Operator of Petroleum & Chemical Storage Terminals

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Netherlands—continued
	1,088,187	Arcadis	$	18,126
		Engineering Consultant
	2,051,535	Aalberts Industries		16,142
		Flow Control & Heat Treatment
	244,969	Smit Internationale		14,519
		Harbor & Offshore Towage & Marine Services
	650,000	QIAGEN (b)		12,064
		Life Science Tools & Molecular Diagnostics
				200,220
		> Germany 4.7%
	524,000	Wincor Nixdorf		29,385
		Retail POS Systems & ATM Machines
	700,000	CTS Eventim		28,355
		Event Ticket Sales
	200,000	Vossloh		24,056
		Rail Infrastructure & Diesel Locomotives
	1,010,947	Rhoen-Klinikum		22,354
		Health Care Services
	155,000	Rational		17,880
		Commercial Oven Manufacturer
	595,000	Elringklinger		9,925
		Automobile Components
	744,400	Tognum		9,807
		Diesel Engines for Drive & Power Generation Systems
	700,000	Takkt		7,463
		Mail Order Retailer of Office & Warehouse Durables
	354,500	Deutsche Beteiligungs		6,067
		Private Equity Investment Management
				155,292
		> France 4.6%
	295,000	Neopost		26,528
		Postage Meter Machines
	211,000	Iliad		20,495
		Alternative Internet & Telecoms Provider
	944,000	SES		18,023
		Satellite Broadcasting Services
	441,635	SAFT		17,544
		Niche Battery Manufacturer
	222,118	Pierre & Vacances		15,453
		Vacation Apartment Lets
	155,900	Rubis		11,610
		Tank Storage & Liquefied Petroleum Gas Distributor
	190,000	Eurofins Scientific		11,169
		Food Screening & Testing
	399,598	Carbone Lorraine		10,984
		Advanced Industrial Materials
	393,000	Eutelsat		10,153
		Co-leader in European Fixed Satellite Services
	160,701	Norbert Dentressangle		8,009
		Transport
	725,898	Hi-Media (b)		3,633
		Leading Online Advertiser in Europe
				153,601

Number of Shares			Value (000)
		> Switzerland 2.3%
	20,500	Sika	$	22,756
		Chemicals for Construction & Industrial Applications
	275,000	Kuehne & Nagel		21,588
		Freight Forwarding/Logistics
	167,000	Geberit		20,582
		Plumbing Supplies
	85,000	Burckhardt Compression		11,013
		Gas Compression Pumps
				75,939
		> Sweden 2.2%
	3,944,000	Hexagon		35,681
		Measurement Equipment
	3,235,000	SWECO		16,357
		Engineering Consultants
	4,572,226	Nobia (b)		16,320
		Kitchen Cabinet Manufacturing & Sales
	750,000	East Capital Explorer (b)		6,014
		Sweden-based RUS/CEE Investment Fund
				74,372
		> Finland 2.0%
	1,310,000	Stockmann		27,828
		Department Store & Fashion Retailer in Scandinavia & Russia
	1,756,000	Poyry		24,911
		Engineering Consultants
	2,170,000	Ramirent (b)		13,357
		Largest Equipment Rental Company in Scandinavia & Central Eastern Europe
				66,096
		> Ireland 1.4%
	8,100,000	United Drug		22,501
		Irish Pharmaceutical Wholesaler & Outsourcer
	600,000	Aryzta (b)		19,210
		Baked Goods
	286,000	Paddy Power		6,674
		Irish Betting Services
				48,385
		> Italy 1.2%
	15,569,356	CIR (b)		25,755
		Italian Holding Company
	2,045,000	Credito Emiliano (b)		9,815
		Italian Regional Bank
	900,615	GranitiFiandre		3,243
		Innovative Stoneware
				38,813
		> Poland 0.8%
	975,900	Central European Distribution (b)		25,930
		Vodka Production & Spirits Distribution
				25,930
		> Denmark 0.7%
	297,000	Novozymes		24,140
		Industrial Enzymes
				24,140

See accompanying notes to financial statements.

Columbia Acorn International

Statement of Investments (Unaudited), continued

Number of Shares				Value (000)
		> Spain 0.7%
	532,000	Red Electrica de Espana		$	24,070
		Spanish Power Grid
					24,070
		> Greece 0.6%
	3,427,000	Intralot			20,660
		Lottery & Gaming Systems & Services
			��		20,660
		> Czech Republic 0.5%
	114,000	Komercni Banka			15,817
		Leading Czech Republic Universal Bank
					15,817
Europe: Total					1,157,482
Other Countries 11.7%
		> United States 3.6%
	1,340,000	Atwood Oceanics (b)			33,379
		Offshore Drilling Contractor
	475,000	Alexion Pharmaceuticals (b)			19,532
		Biotech Focused on Orphan Diseases
	275,000	Oceaneering International (b)			12,430
		Provider of Sub-sea Services & Manufactured Products
	180,000	Cephalon (b)			10,197
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	251,000	FMC Technologies (b)			9,433
		Oil & Gas Wellhead Manufacturer
	300,000	Bristow (b)			8,889
		Largest Provider of Helicopter Services to Offshore Oil & Gas Producers
	200,000	World Fuel Services			8,246
		Global Fuel Broker
	460,000	BioMarin (b)			7,181
		Biotech Focused on Orphan Diseases
	150,000	Illumina (b)			5,841
		Leading Tools & Service Provider for Genetic Analysis
	150,000	Ritchie Brothers Auctioneers (c)			3,517
		Heavy Equipment Auctioneer
	324,000	Tesco (b)			2,573
		Developing New Well Drilling Technologies
					121,218
		> Canada 2.4%
	1,710,000	ShawCor			29,594
		Oil & Gas Pipeline Products
	1,117,000	CCL Industries			22,059
		Leading Global Label Manufacturer
	1,897,000	TriStar Oil & Gas (b)			17,924
		Canadian Oil & Gas Producer
	850,000	Ivanhoe Mines (b)			4,713
	744,000	Ivanhoe Mines (b)			4,166
		Copper Mine Project in Mongolia
	2,262,100	Horizon North Logistics (b)			2,042
		Provides Diversified Oil Service Offering in Northern Canada
					80,498

Number of Shares			Value (000)
		> Australia 2.3%
	7,140,000	Sino Gold (b)	$	29,624
		Gold Mining in The People's Republic of China
	536,000	Australian Stock Exchange		15,925
		Australian Equity & Derivatives Market Operator
	624,735	Perpetual Trustees		14,305
		Mutual Fund Management
	2,000,000	Billabong International		14,055
		Action Sports Apparel Brand Manager
	70,000	Cochlear		3,252
		Cochlear Implants for Hearing
				77,161
		> South Africa 2.3%
	1,973,000	Naspers		51,999
		Media in Africa & Other Emerging Markets
	4,600,000	Mr. Price		16,761
		South African Retailer of Apparel, Household & Sporting Goods
	3,049,000	Uranium One (b)		6,999
		Uranium Mines in Kazakhstan, the U.S. & Australia
				75,759
		> Israel 0.9%
	2,890,000	Israel Chemicals		28,448
		Producer of Potash, Phosphates, Bromine & Specialty Chemicals
				28,448
		> Kazakhstan 0.2%
	1,770,000	Halyk Savings Bank of Kazakhstan - GDR (b)		7,369
		Largest Retail Bank & Insurer in Kazakhstan
				7,369
		> New Zealand —%
	868,418	Sky City Entertainment		1,499
		Casino/Entertainment Complex
				1,499
Other Countries: Total				391,952
Latin America 5.4%
		> Brazil 2.8%
	5,500,000	Localiza Rent A Car		33,963
		Car Rental
	4,300,000	Suzano (b)		33,268
		Brazilian Pulp & Paper Producer
	2,000,000	Natura		26,394
		Direct Retailer of Cosmetics
				93,625
		> Mexico 1.7%
	18,000,000	Urbi Desarrollos Urbanos (b)		27,338
		Affordable Housing Builder
	700,000	Grupo Aeroportuario del Sureste - ADR		27,300
		Mexican Airport Operator
				54,638

See accompanying notes to financial statements.

Number of Shares or Principal Amount (000)			Value (000)
		> Chile 0.9%
	862,000	Sociedad Quimica y Minera de Chile - ADR	$	31,196
		Producer of Specialty Fertilizers, Lithium & Iodine
				31,196
Latin America: Total				179,459
Total Equities: 94.4% (Cost: $2,898,869)				3,147,931
Securities Lending Collateral: 0.1%
	1,944,000	Dreyfus Government Cash Management Fund (d) (7 day yield of 0.150%)		1,944
Total Securities Lending Collateral: (Cost: $1,944)				1,944
Short-Term Obligations: 4.9%
		> Repurchase Agreement 4.4%
$	146,027	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.0001%, collateralized by U.S. Government Agency obligations with various maturities to 3/15/16, market value $148,951 (repurchase proceeds $146,027)		146,027
				146,027
		> Commercial Paper 0.5%
	16,800	Toyota Motor Credit 0.26% due 7/06/09		16,800
				16,800
Total Short-Term Obligations: (Amortized Cost: $162,827)				162,827
Total Investments: 99.4% (Cost: $3,063,640)(e)(f)				3,312,702
Obligation to Return Collateral for Securities Loaned: (0.1)%				(1,944	)
Cash and Other Assets Less Liabilities: 0.7%				22,744
Total Net Assets: 100.0%			$	3,333,502

ADR = American Depositary Receipts.

GDR = Global Depositary Receipts.

See accompanying notes to financial statements.

Columbia Acorn International

Statement of Investments (Unaudited), continued

> Notes to Statement of Investments (dollar values in thousands)

(a) An affiliated person of the Fund may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in these affiliated companies during the six months ended June 30, 2009, are as follows:

Affiliates	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 6/30/09		Value		Dividend
Ain Pharmaciez		643,000		-		-		643,000	$	13,332	$	185
Koninklijke TenCate		1,556,239		78,456		261,706		1,372,989		33,254		725
Unit 4 Aggresso		1,385,000		-		-		1,385,000		22,654		-
Total of Affiliated Transactions		3,584,239		78,456		261,706		3,400,989	$	69,240	$	910

The aggregate cost and value of these companies at June 30, 2009, were $59,544 and $69,240, respectively. Investments in affiliated companies represented 2.1% of total net assets at June 30, 2009.

(b) Non-income producing security.

(c) All or a portion of this security was on loan at June 30, 2009. The total market value of securities on loan at June 30, 2009 was $1,905.

(d) Investment made with cash collateral received from securities lending activity.

(e) At June 30, 2009, for federal income tax purposes cost of investments was $3,063,640, and net unrealized apppreciation was $249,062 consisting of gross unrealized appreciation of $722,387 and gross unrealized depreciation of $473,325.

(f) On June 30, 2009, the Fund's total investments were denominated in currencies as follows:

Currency	Value		Percentage of Net Assets
Euro	$	712,267		21.4
Japanese Yen		612,747		18.4
U.S. Dollar		450,674		13.5
British Pound		220,543		6.6
Hong Kong Dollar		207,546		6.2
Other currencies less than 5% of total net assets		1,108,925		33.3
	$	3,312,702		99.4

At June 30, 2009, the Fund had entered into the following forward foreign currency exchange contracts:

Forward Foreign Currency Contracts to Buy	Forward Foreign Currency Contracts to Sell	Principal Amount in Foreign Currency		Principal Amount in U.S. Dollar		Settlement Date	Unrealized Appreciation
AUD	USD		6,917	$	5,000	7/15/2009	$	569
AUD	USD		13,288		10,000	8/14/2009		674
CAD	USD		24,233		20,000	7/15/2009		835
CAD	USD		17,589		15,000	8/14/2009		125
JPY	USD		1,977,760		20,000	7/15/2009		533
JPY	USD		2,452,150		25,000	9/15/2009		476
				$	95,000		$	3,212
Forward Foreign Currency Contracts to Buy	Forward Foreign Currency Contracts to Sell	Principal Amount in Foreign Currency		Principal Amount in U.S. Dollar		Settlement Date	Unrealized (Depreciation)
AUD	USD		18,581	$	15,000	9/15/2009	$	(110	)
CAD	USD		33,561		30,000	9/15/2009		(1,134	)
JPY	USD		2,384,325		25,000	8/14/2009		(238	)
USD	EUR		33,940		45,000	7/15/2009		(2,614	)
USD	EUR		36,714		50,000	8/14/2009		(1,503	)
USD	EUR		49,938		70,000	9/15/2009		(47	)
				$	235,000		$	(5,646	)

The counterparty for all forward foreign currency exchange contracts is State Street Bank and Trust Company.

AUD = Australian Dollar

CAD = Canadian Dollar

EUR = Euro

JPY = Japanese Yen

USD = United States Dollar

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)		Total
Equities
Total Asia	$	55,121	$	1,363,917		$	-	$	1,419,038
Total Europe		39,534		1,117,948			-		1,157,482
Total Other Countries		208,715		183,237			-		391,952
Total Latin America		179,459		-			-		179,459
Total Equities		482,829		2,665,102			-		3,147,931
Securities Lending Collateral		1,944		-			-		1,944
Short-Term Obligations		-		162,827			-		162,827
Total Investments	$	484,773	$	2,827,929		$	-	$	3,312,702
Net Forward Foreign Currency Exchange Contracts	$	-	$	(2,434	)	$	-	$	(2,434	)
Total	$	484,773	$	2,825,495		$	-	$	3,310,268

The Fund's assets assigned to the Level 2 input category include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation.

Investments in Secruities	Balance as of December 31, 2008		Accrued Discounts/ Premiums		Realized Gain/(Loss)		Change in Unrealized Appreciation (Depreciation)		Net Purchases		Net Sales		Net transfers into Level 3		Net transfers out of Level 3			Balance as of June 30, 2009		Change in Unrealized Appreciation (Depreciation) from Investments held at June 30, 2009
Asia
Hong Kong	$	312	$	-	$	-	$	-	$	-	$	-	$	-	$	(312	)	$	-	$	-
Total	$	312	$	-	$	-	$	-	$	-	$	-	$	-	$	(312	)	$	-	$	-

See accompanying notes to financial statements.

Columbia Acorn International

Portfolio Diversification

At June 30, 2009, the Fund's portfolio investments as a percentage of net assets were diversified as follows:

	Value (000)		Percentage of Net Assets
> Industrial Goods & Services
Industrial Materials & Specialty Chemicals	$	253,329		7.6
Other Industrial Services		251,676		7.5
Machinery		197,273		5.9
Outsourcing Services		124,920		3.7
Electrical Components		63,501		1.9
Conglomerates		34,020		1.0
Construction		33,214		1.0
Medical Equipment & Devices		14,187		0.4
Industrial Distribution		7,290		0.2
Waste Management		5,130		0.2
		984,540		29.4
> Consumer Goods & Services
Retail		118,853		3.6
Other Consumer Services		89,533		2.7
Nondurables		84,549		2.5
Food & Beverage		84,026		2.5
Apparel		61,345		1.8
Casinos & Gaming		58,282		1.7
Travel		49,416		1.5
Other Entertainment		46,830		1.4
Consumer Goods Distribution		25,930		0.8
Educational Services		25,731		0.8
Furniture & Textiles		16,320		0.5
Consumer Electronics		10,704		0.3
		671,519		20.1
> Information
Financial Processors		76,123		2.3
Computer Hardware & Related Equipment		59,179		1.8
Internet Related		54,348		1.6
TV Broadcasting		51,999		1.6
Instrumentation		46,737		1.4
Publishing		40,026		1.2
Satellite Broadcasting & Services		28,176		0.8
CATV		23,882		0.7
Business Software		22,654		0.7
Semiconductors & Related Equipment		14,859		0.4
Business Information & Marketing Services		13,190		0.4
Advertising		9,743		0.3
		440,916		13.2
> Other Industries
Real Estate		168,885		5.1
Transportation		115,507		3.5
Conglomerates		25,755		0.8
Regulated Utilities		24,070		0.7
		334,217		10.1

	Value (000)			Percentage of Net Assets
> Energy & Minerals
Oil Services	$	125,827			3.8
Mining		59,106			1.8
Oil Refining, Marketing & Distribution		54,214			1.6
Agricultural Commodities		33,268			1.0
Oil & Gas Producers		28,599			0.9
		301,014			9.1
> Finance
Brokerage & Money Management		92,786			2.8
Banks		88,038			2.6
Finance Companies		40,928			1.2
Savings & Loans		22,075			0.7
		243,827			7.3
> Health Care
Medical Equipment & Devices		94,018			2.8
Pharmaceuticals		36,281			1.1
Health Care Services		22,354			0.7
Medical Supplies		12,064	��		0.4
Biotechnology & Drug Delivery		7,181			0.2
		171,898			5.2
Total Equities:		3,147,931			94.4
Securities Lending Collateral:		1,944			0.1
Short-Term Obligations:		162,827			4.9
Total Investments:		3,312,702			99.4
Obligation to Return Collateral for Securities Loaned:		(1,944	)		(0.1	)
Cash and Other Assets Less Liabilities:		22,744			0.7
Net Assets:	$	3,333,502			100.0

See accompanying notes to financial statements.

Columbia Acorn USA

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Information
Bally Technologies		410,000		570,000
Blue Coat Systems		0		83,724
Cogent Communications		240,000		840,000
CommScope		0		335,000
Entegris		0		750,000
Informatica		943,000		1,093,000
ManTech International		0		50,000
Monolithic Power Systems		100,000		340,000
Netgear		0		135,000
NetSuite		150,000		240,000
Pericom Semiconductor		225,000		480,000
SBA Communications		0		130,000
Switch & Data Facilities		870,500		947,000
tw telecom		1,736,000		2,061,000
Consumer Goods & Services
American Apparel		0		334,296
Avis Budget Group		0		907,750
Bebe Stores		0		262,000
Cavco Industries		306,672		337,900
Charlotte Russe		0		270,878
Charming Shoppes		0		609,879
Chico's FAS		607,000		824,000
Children's Place Retail Stores		60,000		90,000
Gaylord Entertainment		411,000		528,969
Hertz		0		750,000
Interface		0		349,300
J Crew Group		154,000		246,000
Knoll		580,000		780,000
Lifetime Fitness		0		110,000
Lululemon Athletica		0		165,000
New York & Company		0		333,700
Saks		0		459,000
Universal Technical Institute		0		165,000
Industrial Goods & Services
Albany International		0		150,000
Drew Industries		238,889		255,000
GrafTech International		0		200,000
HEICO		0		100,000
Interline Brands		225,000		375,000
M/I Homes		140,000		240,000
Oshkosh		0		200,000
Ritchie Brothers Auctioneers		0		110,000

	Number of Shares
	03/31/09		06/30/09
Finance
CIT Group		0		700,000
Delphi Financial Group		0		110,000
GATX		205,000		365,000
H&E Equipment Services		514,396		625,000
McGrath Rentcorp		220,000		345,000
MF Global		0		750,000
Wilmington Trust		0		140,000
Health Care
American Medical Systems		33,398		100,000
Auxilium Pharmaceuticals		125,000		165,000
Cepheid		345,900		450,000
Luminex		260,100		350,000
Medarex		320,000		445,000
NPS Pharmaceuticals		0		290,935
Energy & Minerals
Atwood Oceanics		555,000		720,000
Carrizo Oil & Gas		315,000		485,000
Oceaneering International		75,111		130,111
Other Industries
Corporate Office Properties		113,100		170,000
DCT Industrial Trust		0		470,000
Kite Realty Group		150,000		1,450,000
Macerich Company		0		266,953
SL Green Realty		110,000		405,000

See accompanying notes to financial statements.

Columbia Acorn USA

Major Portfolio Changes in the Second Quarter (Unaudited), continued

	Number of Shares
	03/31/09		06/30/09
Sales
Information
American Tower		376,000		100,000
Flir Systems		700,000		460,740
Tellabs		528,000		0
Consumer Goods & Services
Abercrombie & Fitch		357,000		281,000
ITT Educational Services		232,000		202,000
True Religion Apparel		600,213		381,313
Industrial Goods & Services
Administaff		175,000		85,000
ESCO Technologies		650,300		625,300
Pentair		533,600		500,000
Simpson Manufacturing		195,000		0
Waste Connections		280,875		130,000
Finance
HCC Insurance Holdings		714,500		0
People's United		407,040		77,040
Health Care
Cephalon		145,000		125,000
Lincare Holdings		126,800		0
Meridian Biosciences		105,000		0
Savient Pharmaceuticals		400,000		280,000

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 98.1%
Information 32.5%
		> Business Software 7.7%
	1,093,000	Informatica (a)	$	18,789
		Enterprise Data Integration Software
	695,100	Micros Systems (a)		17,600
		Information Systems for Restaurants & Hotels
	2,100,000	Novell (a)		9,513
		Directory, Operating System & Identity Management Software
	305,000	ANSYS (a)		9,504
		Simulation Software for Engineers & Designers
	288,000	Concur Technologies (a)		8,951
		Web Enabled Cost & Expense Management Software
	525,000	Blackbaud		8,164
		Software & Services for Non-profits
	100,000	Quality Systems (b)		5,696
		IT Systems for Medical Groups & Ambulatory Care Centers
	240,000	NetSuite (a)(b)		2,834
		End to End IT Systems Solution Delivered Over the Web
	100,000	Avid Technology (a)		1,341
		Digital Nonlinear Editing Software & Systems
	180,000	Art Technology Group (a)		684
		Software & Tools to Optimize Websites for E-Commerce
	114,300	Actuate (a)		546
		Information Delivery Software & Solutions
				83,622
		> Semiconductors & Related Equipment 4.0%
	760,000	Microsemi (a)		10,488
		Analog/Mixed-signal Semiconductors
	1,179,750	ON Semiconductor (a)		8,093
		Mixed-signal & Power Management Semiconductors
	340,000	Monolithic Power Systems (a)		7,619
		High Performance Analog & Mixed Signal Integrated Circuits (ICs)
	1,168,000	Integrated Device Technology (a)		7,055
		Communications Semiconductors
	189,296	Supertex (a)		4,753
		Analog/Mixed-signal Semiconductors
	480,000	Pericom Semiconductor (a)		4,042
		Interface Integrated Circuits (ICs) & Frequency Control Products
	750,000	Entegris (a)		2,040
		Semiconductor Materials Management Products
				44,090
		> Instrumentation 3.4%
	180,000	Mettler Toledo (a)		13,887
		Laboratory Equipment
	460,740	FLIR Systems (a)		10,394
		Infrared Cameras
	775,000	IPG Photonics (a)		8,502
		Fiber Lasers

Number of Shares			Value (000)
	168,000	Trimble Navigation (a)	$	3,298
		GPS-based Instruments
	36,000	FARO Technologies (a)		559
		Precision Measurement Equipment
				36,640
		> Mobile Communications 3.3%
	1,250,000	Crown Castle International (a)		30,025
		Communications Towers
	130,000	SBA Communications (a)		3,190
		Communications Towers
	100,000	American Tower (a)		3,153
		Communications Towers in USA & Latin America
	88,000	Globalstar (a)		93
		Satellite Mobile Voice & Data Carrier
				36,461
		> Computer Hardware & Related Equipment 3.0%
	505,000	II-VI (a)		11,196
		Laser Optics & Specialty Materials
	295,600	Amphenol		9,353
		Electronic Connectors
	280,000	Nice Systems - ADR (Israel) (a)		6,460
		Audio & Video Recording Solutions
	184,000	Zebra Technologies (a)		4,353
		Bar Code Printers
	135,000	Netgear (a)		1,945
		Networking Products for Small Business & Home
				33,307
		> Telephone and Data Services 2.8%
	2,061,000	tw telecom (a)		21,166
		Fiber Optic Telephone/Data Services
	840,000	Cogent Communications (a)		6,846
		Internet Data Pipelines
	800,000	PAETEC Holding (a)		2,160
		Telephone/Data Services for Business
				30,172
		> Telecommunications Equipment 1.9%
	525,000	Polycom (a)		10,642
		Video Conferencing Equipment
	335,000	CommScope (a)		8,797
		Wireless Infrastructure Equipment & Telecom Cable
	83,724	Blue Coat Systems (a)		1,385
		WAN Acceleration & Network Security
				20,824
		> Gaming Equipment & Services 1.7%
	570,000	Bally Technologies (a)		17,054
		Slot Machines & Software
	100,000	Scientific Games (a)		1,577
		Lottery Services Provider
				18,631
		> Financial Processors 1.7%
	483,280	Global Payments		18,104
		Credit Card Processor
				18,104

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Internet Related 1.4%
	947,000	Switch & Data Facilities (a)	$	11,108
		Network Neutral Data Centers
	40,000	Equinix (a)		2,910
		Network Neutral Data Centers
	381,740	TheStreet.com		798
		Financial Information Websites
				14,816
		> Computer Services 1.2%
	275,000	SRA International (a)		4,829
		Government IT Services
	1,005,500	Hackett Group (a)		2,343
		IT Integration & Best Practice Research
	50,000	ManTech International (a)		2,152
		Government IT Services
	786,000	RCM Technologies (a)(c)		1,745
		Technology & Engineering Services
	235,000	iGate		1,555
		IT & Business Process Outsourcing Services
				12,624
		> Contract Manufacturing 0.2%
	115,000	Plexus (a)		2,353
		Electronic Manufacturing Services
				2,353
		> CATV 0.1%
	305,785	Mediacom Communications (a)		1,563
		CATV Franchises
				1,563
		> Radio 0.1%
	511,100	Salem Communications (a)		491
		Radio Stations for Religious Programming
	705,500	Spanish Broadcasting System (a)		127
		Spanish Language Radio Stations
	18,750	Saga Communications (a)		96
		Radio Stations in Small & Mid-sized Cities
				714
		> TV Broadcasting —%
	975,000	Entravision Communications (a)		468
		Spanish Language TV & Radio Stations
				468
Information: Total				354,389
Consumer Goods & Services 15.0%
		> Retail 5.0%
	402,000	Urban Outfitters (a)		8,390
		Apparel & Home Specialty Retailer
	824,000	Chico's FAS (a)		8,017
		Women's Specialty Retailer
	281,000	Abercrombie & Fitch		7,135
		Teen Apparel Retailer
	246,000	J Crew Group (a)(b)		6,647
		Multi-channel Branded Retailer
	497,714	Hot Topic (a)		3,638
		Music Inspired Retailer of Apparel, Accessories & Gifts
	270,878	Charlotte Russe (a)		3,489
		Value Fashion Retailer

Number of Shares			Value (000)
	480,000	Talbots (b)	$	2,592
		Women's Specialty Retailer
	90,000	Children's Place Retail Stores (a)		2,379
		Specialty Children's Retailer
	609,879	Charming Shoppes (a)		2,269
		Women's Specialty Plus Size Apparel Retailer
	165,000	Lululemon Athletica (a)(b)		2,150
		Premium Active Apparel Retailer
	459,000	Saks (a)		2,033
		Luxury Department Store Retailer
	262,000	Bebe Stores		1,802
		Women's Contemporary Specialty Apparel Retailer
	94,000	Hibbett Sports (a)		1,692
		Sporting Goods Retailer
	334,296	American Apparel (a)		1,217
		Vertically Integrated Apparel Retailer
	333,700	New York & Company (a)		1,031
		Women's Specialty Retailer
				54,481
		> Educational Services 2.1%
	202,000	ITT Educational Services (a)		20,333
		Post-secondary Degree Services
	165,000	Universal Technical Institute (a)		2,464
		Vocational Training
				22,797
		> Travel 2.0%
	528,969	Gaylord Entertainment (a)(b)		6,723
		Convention Hotels
	750,000	Hertz (a)		5,992
		Largest U.S. Rental Car Operator
	907,750	Avis Budget Group (a)		5,129
		Second Largest Car Rental Company
	150,000	Vail Resorts (a)		4,023
		Ski Resort Operator & Developer
				21,867
		> Apparel 1.3%
	381,313	True Religion Apparel (a)		8,503
		Premium Denim
	222,200	Coach		5,973
		Designer & Retailer of Branded Leather Accessories
				14,476
		> Furniture & Textiles 1.1%
	780,000	Knoll		5,912
		Office Furniture
	285,000	Herman Miller		4,372
		Office Furniture
	349,300	Interface		2,166
		Modular & Broadloom Carpet
				12,450
		> Other Durable Goods 0.9%
	337,900	Cavco Industries (a)(c)		8,559
		High End Manufactured Homes
	2,078,300	Champion Enterprises (a)		665
		Manufactured Homes
				9,224

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Consumer Goods Distribution 0.8%
	523,500	Pool	$	8,669
		Distributor of Swimming Pool Supplies & Equipment
				8,669
		> Nondurables 0.5%
	298,000	Jarden (a)		5,588
		Branded Household Products
				5,588
		> Leisure Products 0.4%
	180,000	Thor Industries		3,307
		RV & Bus Manufacturer
	150,000	Winnebago Industries		1,114
		Motor Home Maker
				4,421
		> Casinos & Gaming 0.4%
	455,000	Pinnacle Entertainment (a)		4,227
		Regional Casino Operator
				4,227
		> Food & Beverage 0.3%
	90,000	Hansen Natural (a)		2,774
		Alternative Beverages
				2,774
		> Other Consumer Services 0.2%
	110,000	Lifetime Fitness (a)		2,201
		Sport & Fitness Club Operator
				2,201
Consumer Goods & Services: Total				163,175
Industrial Goods & Services 14.7%
		> Machinery 10.3%
	625,300	ESCO Technologies (a)		28,013
		Automatic Electric Meter Readers
	627,500	Ametek		21,699
		Aerospace/Industrial Instruments
	445,000	Donaldson		15,415
		Industrial Air Filtration
	373,600	Nordson		14,443
		Dispensing Systems for Adhesives & Coatings
	500,000	Pentair		12,810
		Pumps & Water Treatment
	195,000	MOOG (a)		5,033
		Motion Control Products for Aerospace, Defense & Industrial Markets
	155,000	Mine Safety Appliances		3,736
		Safety Equipment
	100,000	HEICO		2,926
		FAA Approved Aircraft Replacement Parts
	200,000	Oshkosh		2,908
		Specialty Truck Manufacturer
	71,800	Toro (b)		2,147
		Turf Maintenance Equipment
	60,000	Clarcor		1,751
		Mobile & Industrial Filters
	50,000	Kaydon		1,628
		Specialized Friction & Motion Control Products
				112,509

Number of Shares			Value (000)
		> Industrial Materials & Specialty Chemicals 1.2%
	255,000	Drew Industries (a)	$	3,104
		RV & Manufactured Home Components
	163,000	Nalco Holding Company		2,745
		Provider of Water Treatment & Process Chemicals & Services
	50,000	Greif		2,211
		Industrial Packaging
	65,000	Koppers Holdings		1,714
		Integrated Provider of Carbon Compounds
	150,000	Albany International		1,707
		Paper Machine Clothing & Advanced Textiles
	60,000	Albemarle		1,534
		Refinery Catalysts & Other Specialty Chemicals
				13,015
		> Outsourcing Services 0.9%
	350,000	Quanta Services (a)		8,095
		Electrical & Telecom Construction Services
	85,000	Administaff		1,978
		Professional Employer Organization
				10,073
		> Other Industrial Services 0.5%
	396,000	American Reprographics (a)		3,295
		Document Management & Logistics
	265,000	TrueBlue (a)		2,226
		Temporary Manual Labor
				5,521
		> Industrial Distribution 0.5%
	375,000	Interline Brands (a)		5,130
		Industrial Distribution
				5,130
		> Construction 0.4%
	110,000	Ritchie Brothers Auctioneers (b)		2,579
		Heavy Equipment Auctioneer
	240,000	M/I Homes (a)		2,350
		Columbus-based Home Builder
				4,929
		> Electrical Components 0.4%
	145,000	Acuity Brands		4,067
		Commercial Lighting Fixtures
				4,067
		> Waste Management 0.3%
	130,000	Waste Connections (a)		3,368
		Solid Waste Management
				3,368
		> Steel 0.2%
	200,000	GrafTech International (a)		2,262
		Industrial Graphite Materials Producer
				2,262
Industrial Goods & Services: Total				160,874

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
Finance 13.8%
		> Finance Companies 5.2%
	1,136,500	AmeriCredit (a)(b)	$	15,400
		Auto Lending
	365,000	GATX		9,388
		Rail Car Lessor
	275,000	Aaron's		8,200
		Rent to Own
	407,900	World Acceptance (a)		8,121
		Personal Loans
	345,000	McGrath Rentcorp		6,576
		Temporary Space & IT Rentals
	625,000	H&E Equipment Services (a)		5,844
		Heavy Equipment Leasing
	700,000	CIT Group		1,505
		Middle Market Lender, Equipment Leasing & Vendor Finance/Factoring
	230,000	CAI International (a)		1,173
		International Container Leasing
	99,200	Marlin Business Services (a)		555
		Small Equipment Leasing
				56,762
		> Banks 4.7%
	935,182	Valley National Bancorp		10,942
		New Jersey/New York Bank
	659,800	TCF Financial		8,821
		Great Lakes Bank
	414,088	Lakeland Financial		7,868
		Indiana Bank
	508,000	Pacific Continental		6,162
		Pacific N.W. Bank
	468,025	MB Financial		4,769
		Chicago Bank
	103,000	SVB Financial Group (a)		2,804
		Bank to Venture Capitalists
	213,600	Associated Banc-Corp		2,670
		Midwest Bank
	140,000	Wilmington Trust		1,912
		Delaware Trust Bank
	46,000	BOK Financial		1,733
		Tulsa-based Southwest Bank
	851,247	Guaranty Bancorp (a)		1,626
		Colorado Bank
	90,000	TriCo Bancshares		1,395
		California Central Valley Bank
	166,527	Green Bankshares (b)		746
		Tennessee Bank
				51,448
		> Brokerage & Money Management 1.6%
	280,000	Eaton Vance		7,490
		Specialty Mutual Funds
	750,000	MF Global (a)		4,448
		Futures Broker
	155,000	Investment Technology Group (a)		3,160
		Electronic Trading
	150,000	SEI Investments		2,706
		Mutual Fund Administration & Investment Management
				17,804

Number of Shares			Value (000)
		> Savings & Loans 1.4%
	600,000	ViewPoint Financial	$	9,138
		Texas Thrift
	238,090	Berkshire Hills Bancorp		4,947
		Northeast Thrift
	77,040	People's United		1,159
		Connecticut Savings & Loan
	42,231	K-Fed Bancorp		388
		Los Angeles Savings & Loan
				15,632
		> Insurance 0.9%
	120,000	Tower Group		2,974
		Commercial & Personal Lines Insurance
	75,000	Endurance Specialty Holdings		2,197
		Commercial Lines Insurance/Reinsurance
	110,000	Delphi Financial Group		2,137
		Workers Compensation & Group Employee Benefit Products & Services
	7,000	Markel (a)		1,972
		Specialty Insurance
				9,280
Finance: Total				150,926
Health Care 10.3%
		> Biotechnology & Drug Delivery 3.6%
	180,000	Myriad Genetics (a)		6,416
		Genetic Diagnostics
	165,000	Auxilium Pharmaceuticals (a)		5,178
		Biotech Focused on Niche Disease Areas
	474,700	Seattle Genetics (a)		4,614
		Antibody-based Therapies for Cancer
	270,000	BioMarin (a)		4,215
		Biotech Focused on Orphan Diseases
	280,000	Savient Pharmaceuticals (a)		3,881
		Biotech Company Focused on Niche Disease Areas
	445,000	Medarex (a)		3,716
		Humanized Antibodies
	43,000	United Therapeutics (a)		3,583
		Biotech Focused on Rare Diseases
	518,295	Nektar Therapeutics (a)		3,358
		Drug Delivery Technologies
	161,286	InterMune (a)		2,451
		Drugs for Pulmonary Fibrosis & Hepatitis C
	290,935	NPS Pharmaceuticals (a)		1,356
		Orphan Drugs & Healthy Royalties
	500,000	IsoRay (a)		125
	100,000	IsoRay - Warrants (a)(d)		5
		Radiology Cancer Company
	19,425	Poniard (a)		116
		Cancer Biotech
	18,181	Metabolex, Series A-1 (a)(d)		19
		Diabetes Drug Development
	738,060	Medicure - Warrants (a)(d)
		Cardiovascular Biotech Company		7
	37,500	Locus Pharmaceuticals, Series A-1, Pfd. (a)(d)		3
	19,329	Locus Pharmaceuticals, Series B-1, Pfd. (a)(d)		2
		High Throughput Rational Drug Design
				39,045

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Medical Supplies 2.4%
	158,300	Techne	$	10,101
		Cytokines, Antibodies & Other Reagents for Life Science
	350,000	Luminex (a)		6,489
		Life Science Tools & Molecular Diagnostics
	450,000	Cepheid (a)		4,239
		Molecular Diagnostics
	180,000	Immucor (a)		2,477
		Automated Blood Typing Reagents
	53,000	Idexx Laboratories (a)		2,449
		Diagnostic Equipment & Services for Veterinarians
				25,755
		> Health Care Services 1.9%
	606,300	PSS World Medical (a)		11,223
		Distributor of Medical Supplies
	242,000	Psychiatric Solutions (a)		5,503
		Behavioral Health Services
	67,000	Charles River Laboratories (a)		2,261
		Pharmaceutical Research
	283,000	eResearch Technology (a)		1,757
		Clinical Research Services
				20,744
		> Medical Equipment & Devices 1.8%
	235,000	Alexion Pharmaceuticals (a)		9,663
		Biotech Focused on Orphan Diseases
	169,000	Illumina (a)		6,581
		Leading Tools & Service Provider for Genetic Analysis
	100,000	American Medical Systems (a)		1,580
		Medical Devices to Treat Urological Conditions
	50,000	Kinetic Concepts (a)		1,363
		Wound Healing & Tissue Repair Products
				19,187
		> Pharmaceuticals 0.6%
	125,000	Cephalon (a)		7,081
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	13,603	Myriad Pharmaceuticals (a)		63
		Genetic Diagnostics
				7,144
Health Care: Total				111,875
Energy & Minerals 7.8%
		> Oil Services 4.5%
	598,400	FMC Technologies (a)		22,488
		Oil & Gas Wellhead Manufacturer
	720,000	Atwood Oceanics (a)		17,935
		Offshore Drilling Contractor
	130,111	Oceaneering International (a)		5,881
		Provider of Sub-sea Services & Manufactured Products
	115,375	Exterran Holdings (a)		1,850
		Natural Gas Compressor Rental & Fabrication
	106,000	Tesco (a)		842
		Developing New Well Drilling Technologies
				48,996

Number of Shares			Value (000)
		> Oil & Gas Producers 2.9%
	276,800	Southwestern Energy (a)	$	10,754
		Oil & Gas Producer
	925,000	Quicksilver Resources (a)		8,593
		Natural Gas & Coal Seam Gas Producer
	485,000	Carrizo Oil & Gas (a)		8,318
		Oil & Gas Producer
	111,200	Equitable Resources		3,882
		Natural Gas Producer & Utility
				31,547
		> Other Resources 0.4%
	218,000	Layne Christensen (a)		4,458
		Oil & Gas Production/Engineering & Construction/Contract Drilling
				4,458
Energy & Minerals: Total				85,001
Other Industries 4.0%
		> Real Estate 3.1%
	405,000	SL Green Realty		9,291
		Manhattan Office Buildings
	170,000	Corporate Office Properties		4,986
		Office Buildings
	266,953	Macerich Company (b)		4,701
		Regional Shopping Malls
	1,450,000	Kite Realty Group		4,234
		Community Shopping Centers
	100,000	Digital Realty Trust		3,585
		Technology-focused Office Buildings
	90,000	American Campus Communities		1,996
		Student Housing
	470,000	DCT Industrial Trust		1,917
		Industrial Properties
	196,000	Extra Space Storage		1,637
		Self Storage Facilities
	120,000	BioMed Realty Trust		1,228
		Life Science-focused Office Buildings
				33,575
		> Transportation 0.9%
	524,720	Heartland Express		7,724
		Regional Trucker
	180,000	Rush Enterprises, Class A (a)		2,097
		Truck Sales & Service
				9,821
Other Industries: Total				43,396
Total Equities: 98.1% (Cost: $1,114,810)				1,069,636
Securities Lending Collateral: 2.3%
	24,650,050	Dreyfus Government Cash Management Fund (e) (7 day yield of 0.150%)		24,650
Total Securities Lending Collateral: (Cost: $24,650)				24,650

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), continued

Principal Amount (000)			Value (000)
Short-Term Obligation: 2.0%
		> Repurchase Agreement 2.0%
$	21,703	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 07/01/09 at 0.0001%, collateralized by a U.S. Government Agency obligation, maturing 3/15/16, market value $22,142 (repurchase proceeds $21,703)	$	21,703
Total Short-Term Obligation: (Cost: $21,703)				21,703
Total Investments: 102.4% (Cost: $1,161,163)(f)				1,115,989
Obligation to Return Collateral for Securities Loaned: (2.3)%				(24,650	)
Cash and Other Assets Less Liabilities: (0.1)%				(1,553	)
Total Net Assets: 100%			$	1,089,786

ADR = American Depositary Receipts.

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

(a) Non-income producing security.

(b) All or a portion of this security was on loan at June 30, 2009. The total market value of securities on loan at June 30, 2009 was $23,954.

(c) An affiliated person of the Fund may include any company in which the Fund owns five percent or more of its outstanding voting shares.

Transactions in these affiliated companies during the six months ended June 30, 2009, are as follows:

Affiliate	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 6/30/09		Value		Dividend
RCM Technologies		786,000		-		-		786,000	$	1,745	$	-
Cavco Industries		287,900		50,000		-		337,900		8,559		-
Total Affiliated Transactions		1,073,900		50,000		-		1,123,900	$	10,304	$	-

The aggregate cost and value of these companies at June 30, 2009, were $16,983 and $10,304, respectively. Investments in the affiliated companies represented 0.9% of total net assets at June 30, 2009.

(d) Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued at their fair value determined in good faith under consistently applied procedures established by the board of trustees. At June 30, 2009, these securities amounted to $36, which represented less than 0.01% of total net assets.

Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Metabolex, Series A	2/11/00		18,181	$	2,000	$	19
Medicure - Warrants	12/22/06		738,060		-		7
Locus Pharmaceuticals, Series A-1, Pfd.	9/05/01		37,500		1,500		3
IsoRay - Warrants	3/21/07		100,000		-		5
Locus Pharmaceuticals, Series B-1, Pfd.	2/08/07		19,329		56		2
				$	3,556	$	36

(e) Investment made with cash collateral received from securities lending activity.

(f) At June 30, 2009, for federal income tax purposes cost of investments was $1,161,163 and net unrealized depreciation was $45,174 consisting of gross unrealized appreciation of $238,985 and gross unrealized depreciation of $284,159.

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Equities
Total Information	$	354,389	$	-	$	-	$	354,389
Total Consumer Goods & Services		163,175		-		-		163,175
Total Industrial Goods & Services		160,874		-		-		160,874
Total Finance		150,926		-		-		150,926
Total Health Care		111,839		12		24		111,875
Total Energy & Minerals		85,001		-		-		85,001
Total Other Industries		43,396		-		-		43,396
Total Equities		1,069,600		12		24		1,069,636
Securities Lending Collateral		24,650		-		-		24,650
Short-Term Obligation		-		21,703		-		21,703
Total Investments		1,094,250		21,715		24		1,115,989
Total	$	1,094,250	$	21,715	$	24	$	1,115,989

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), continued

> Notes to Statement of Investments (dollar values in thousands)

Investments in Secruities	Balance as of December 31, 2008		Accrued Discounts/ Premiums		Realized Gain/(Loss)		Change in Unrealized Appreciation (Depreciation)			Net Purchases		Net Sales		Net transfers into Level 3		Net transfers out of Level 3		Balance as of June 30, 2009		Change in Unrealized Appreciation (Depreciation) from Investments held at June 30, 2009
Health Care
Biotechnology & Drug Delivery	$	41	$	-	$	-	$	(17	)	$	-	$	-	$	-	$	-	$	24	$	(17	)
Total	$	41	$	-	$	-	$	(17	)	$	-	$	-	$	-	$	-	$	24	$	(17	)

The change in unrealized depreciation attributable to securities owned at June 30, 2009 which were valued using significant unobservable inputs (Level 3) amounted to $17. This amount is included in net change in unrealized depreciation on the Statement of Changes in Net Assets.

See accompanying notes to financial statements.

Columbia Acorn International Select

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Asia
> Japan
Aeon Mall		182,000		318,000
Benesse		144,300		166,300
Nintendo		22,500		31,500
Rohto Pharmaceutical		502,200		568,300
Suruga Bank		279,000		307,000
> South Korea
MegaStudy		0		42,480
NHN		29,000		71,100
> Singapore
Ascendas REIT		0		2,291,500
OLAM International		0		5,250,000
Singapore Exchange		0		702,000
> Hong Kong
Hong Kong Exchanges and Clearing		370,000		434700
Lifestyle International		0		666,300
NagaCorp		7,798,800		9,776,566
> China
Shandong Weigao		0		1,516,000
> Taiwan
Ishares MSCI Taiwan Index Fund		0		244,800
Europe
> United Kingdom
Capita Group		950,000		1,060,000
Cobham		1,035,000		2,000,000
Intertek Group		561,600		641,600
Serco		2,000,000		2,300,000
> France
Eutelsat		0		117,000
Neopost		29,500		83,500
> Netherlands
Fugro		0		120,162
Imtech		0		169,000
Other Countries
> Canada
CCL Industries		0		134,000
Pacific Rubiales Energy		473,867		1,308,000
Potash Corp. of Saskatchewan		95,400		117,400
> United States
Alexion Pharmaceuticals		107,600		220,000
Atwood Oceanics		0		115,000
> South Africa
Naspers		421,000		630,000

	Number of Shares
	03/31/09		06/30/09
> Israel
Israel Chemicals		620,000		1,203,000
> Australia
Sino Gold		1,205,000		1,275,000
Latin America
> Chile
Sociedad Quimica y Minera de Chile - ADR		90,000		182,000

See accompanying notes to financial statements.

Columbia Acorn International Select

Major Portfolio Changes in the Second Quarter (Unaudited), continued

	Number of Shares
	03/31/09		06/30/09
Sales
Asia
> Japan
Jupiter Telecommunications		15,600		9,000
Ryohin Keikaku		70,000		0
> South Korea
Woongjin Coway		256,000		116,000
> Singapore
ComfortDelGro		1,680,000		0
Europe
> United Kingdom
RPS Group		1,100,000		973,000
Smith & Nephew		896,000		0
> France
SES		471,000		210,000
> Germany
Rhoen-Klinikum		400,000		197,200
> Netherlands
QIAGEN		150,000		0
> Sweden
Hexagon		893,000		669,000
> Ireland
Aryzta		96,000		0
United Drug		2,200,000		2,100,000
> Switzerland
Kuehne & Nagel		39,700		35,700
Swatch Group		18,200		0
Synthes		42,000		0
> Greece
Intralot		654,000		0
Other Countries
> Canada
Pacific Rubiales Energy		276133		0
> United States
BioMarin		110,000		0
Bristow		55000		0
Cephalon		155,000		85,000
Diamond Offshore		78,000		47,000
Oceaneering International		98,000		63,000

See accompanying notes to financial statements.

Columbia Acorn International Select

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 91.7%
Asia 33.7%
		> Japan 19.5%
	1,277,000	Kansai Paint	$	9,143
		Paint Producer in Japan, India, China & Southeast Asia
	31,500	Nintendo		8,669
		Entertainment Software & Hardware
	2,740	Seven Bank		7,165
		ATM Processing Services
	9,000	Jupiter Telecommunications		6,823
		Largest Cable Service Provider in Japan
	166,300	Benesse		6,646
		Education Service Provider
	568,300	Rohto Pharmaceutical		6,412
		Health & Beauty Products
	318,000	Aeon Mall		6,017
		Suburban Shopping Mall Developer, Owner & Operator
	900	Orix JREIT		4,120
		Diversified REIT
	435,000	Kamigumi		3,662
		Port Cargo Handling & Logistics
	307,000	Suruga Bank		2,926
		Regional Bank
	330	Nippon Building Fund		2,824
		Office REIT
	67,000	Ain Pharmaciez		1,389
		Dispensing Pharmacy/Drugstore Operator
				65,796
		> South Korea 6.0%
	71,100	NHN (a)		9,824
		South Korea's Largest Online Search Engine
	42,480	MegaStudy		7,646
		Online Education Service Provider
	116,000	Woongjin Coway		2,815
		South Korean Household Appliance Rental Service Provider
				20,285
		> Singapore 4.4%
	5,250,000	OLAM International		8,778
		Agriculture Supply Chain Manager
	702,000	Singapore Exchange		3,430
		Singapore Equity & Derivatives Market Operator
	2,291,500	Ascendas REIT		2,508
		Singapore Industrial Property Landlord
				14,716
		> Hong Kong 2.6%
	434,700	Hong Kong Exchanges and Clearing		6,750
		Hong Kong Equity & Derivatives Market Operator
	9,776,566	NagaCorp		1,291
		Casino/Entertainment Complex in Cambodia
	666,300	Lifestyle International		866
		Mid to High-end Department Store Operator in Hong Kong & China
				8,907

Number of Shares			Value (000)
		> China 1.2%
	1,516,000	Shandong Weigao	$	3,885
		Vertically Integrated Hospital Consumable Manufacturer
				3,885
Asia: Total				113,589
Europe 31.7%
		> United Kingdom 14.4%
	2,300,000	Serco		15,979
		Facilities Management
	1,060,000	Capita Group		12,497
		White Collar, Back Office Outsourcing
	641,600	Intertek Group		11,063
		Testing, Inspection & Certification Services
	2,000,000	Cobham		5,705
		Aerospace Components
	973,000	RPS Group		3,208
		Environmental Consulting & Planning
				48,452
		> France 4.3%
	83,500	Neopost		7,509
		Postage Meter Machines
	210,000	SES		4,009
		Satellite Broadcasting Services
	117,000	Eutelsat		3,023
		Co-leader in European Fixed Satellite Services
				14,541
		> Germany 3.1%
	110,000	Wincor Nixdorf		6,169
		Retail POS Systems & ATM Machines
	197,200	Rhoen-Klinikum		4,360
		Health Care Services
				10,529
		> Netherlands 2.5%
	120,162	Fugro		4,990
		Sub-sea Oilfield Services
	169,000	Imtech		3,289
		Engineering & Technical Services
				8,279
		> Spain 2.4%
	175,000	Red Electrica de Espana		7,918
		Spanish Power Grid
				7,918
		> Sweden 1.8%
	669,000	Hexagon		6,052
		Measurement Equipment
				6,052
		> Ireland 1.7%
	2,100,000	United Drug		5,834
		Irish Pharmaceutical Wholesaler & Outsourcer
				5,834

See accompanying notes to financial statements.

Columbia Acorn International Select

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Switzerland 0.8%
	35,700	Kuehne & Nagel	$	2,802
		Freight Forwarding/Logistics
				2,802
		> Denmark 0.7%
	29,000	Novozymes		2,357
		Industrial Enzymes
				2,357
Europe: Total				106,764
Other Countries 24.3%
		> Canada 7.3%
	117,400	Potash Corp. of Saskatchewan		10,924
		World's Largest Producer of Potash
	1,308,000	Pacific Rubiales Energy (a)		10,784
	138,067	Pacific Rubiales Energy-Warrants (a)(b)		438
		Oil Production & Exploration in Colombia
	134,000	CCL Industries		2,646
		Leading Global Label Manufacturer
				24,792
		> United States 7.0%
	220,000	Alexion Pharmaceuticals (a)		9,046
		Biotech Focused on Orphan Diseases
	85,000	Cephalon (a)		4,815
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	47,000	Diamond Offshore		3,903
		Offshore Drilling Contractor
	115,000	Atwood Oceanics (a)		2,865
		Offshore Drilling Contractor
	63,000	Oceaneering International (a)		2,848
		Provider of Sub-sea Services & Manufactured Products
				23,477
		> South Africa 4.9%
	630,000	Naspers		16,604
		Media in Africa & Other Emerging Markets
				16,604
		> Israel 3.5%
	1,203,000	Israel Chemicals		11,842
		Producer of Potash, Phosphates, Bromine & Specialty Chemicals
				11,842
		> Australia 1.6%
	1,275,000	Sino Gold (a)		5,290
		Gold Mining in The People's Republic of China
				5,290
Other Countries: Total				82,005

Number of Shares or Principal Amount (000)			Value (000)
Latin America 2.0%
		> Chile 2.0%
	182,000	Sociedad Quimica y Minera de Chile - ADR	$	6,587
		Producer of Specialty Fertilizers, Lithium & Iodine
				6,587
Latin America: Total				6,587
Total Equities: 91.7% (Cost: $293,799)				308,945
Exchange Traded Fund: 0.7%
	244,800	iShares MSCI Taiwan Index Fund		2,470
		Taiwan Exchange Traded Fund
Total Exchange Traded Fund: (Cost: $2,409)				2,470
Short-Term Obligations: 7.0%
		> Repurchase Agreement 6.5%
$	22,021	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/08, due 7/01/09 at 0.0001%, collateralized by a U.S. Treasury obligation, maturing 4/23/14, market value $22,464 (repurchase proceeds $22,021)		22,021
				22,021
		> Commercial Paper 0.5%
	1,600	Toyota Motor Credit 0.26% due 7/06/09		1,600
				1,600
Total Short-Term Obligations: (Amortized Cost: $23,621)				23,621
Total Investments: 99.4% (Cost: $319,829)(c)(d)				335,036
Cash and Other Assets Less Liabilities: 0.6%				1,901
Total Net Assets: 100.0%			$	336,937

ADR = American Depositary Receipts.

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

(a) Non-income producing security.

(b) Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. This security is valued at their fair value determined in good faith under consistently applied procedures established by the board of trustees. At June 30, 2009, this security amounted to $438, which represented 0.13% of total net assets.

Additional information on these securities is as follows:

Security				Acquisition Dates				Shares				Cost				Value
Pacific Rubiales Energy-Warrants					7/12/07				138,067			$	236			$	438

(c) At June 30, 2009, for federal income tax purposes cost of investments was $319,829 and net unrealized appreciation was $15,207 consisting of gross unrealized appreciation of $39,412 and gross unrealized depreciation of $24,205.

(d) On June 30, 2009, the Fund's total investments were denominated in
currencies as follows:

Currency	Value		Percentage of Net Assets
Japanese Yen	$	65,796		19.5
U.S. Dollar		56,155		16.7
British Pound		48,451		14.4
Euro		47,100		14.0
Canadian Dollar		24,792		7.3
Other currencies less than 5% of total net assets		92,742		27.5
	$	335,036		99.4

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Equities
Total Asia	$	-	$	113,589	$	-	$	113,589
Total Europe		-		106,764		-		106,764
Total Other Countries		47,831		34,174		-		82,005
Total Latin America		6,587		-		-		6,587
Total Equities		54,418		254,527		-		308,945
Exchange Traded Fund		2,470		-		-		2,470
Short-Term Obligations		-		23,621		-		23,621
Total Investments		56,888		278,148		-		335,036
Total	$	56,888	$	278,148	$	-	$	335,036

The Fund's assets assigned to the Level 2 input category include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation.

See accompanying notes to financial statements.

Columbia Acorn International Select

Portfolio Diversification

At June 30, 2009, the Fund's portfolio investments as a percentage of net assets were diversified as follows:

	Value (000)		Percentage of Net Assets
> Industrial Goods & Services
Outsourcing Services	$	37,254		11.1
Industrial Materials & Specialty Chemicals		29,929		8.9
Other Industrial Services		17,154		5.1
Machinery		7,509		2.2
Electrical Components		5,705		1.7
		97,551		29.0
> Information
TV Broadcasting		16,604		4.9
Financial Processors		10,180		3.0
Internet Related		9,824		2.9
Consumer Software		8,669		2.6
Satellite Broadcasting & Services		7,032		2.1
CATV		6,823		2.0
Computer Hardware & Related Equipment		6,169		1.8
Instrumentation		6,052		1.8
Business Information & Marketing Services		3,208		1.0
		74,561		22.1
> Energy & Minerals
Mining		16,214		4.8
Oil Services		14,606		4.4
Oil & Gas Producers		11,222		3.3
		42,042		12.5
> Consumer Goods & Services
Other Consumer Services		17,973		5.3
Nondurables		9,058		2.7
Retail		7,406		2.2
Casinos & Gaming		1,291		0.4
		35,728		10.6
> Health Care
Medical Equipment & Devices		12,931		3.8
Pharmaceuticals		10,649		3.2
Health Care Services		4,360		1.3
		27,940		8.3
> Other Industries
Real Estate		9,452		2.8
Regulated Utilities		7,918		2.3
Transportation		3,662		1.1
		21,032		6.2

	Value (000)		Percentage of Net Assets
> Finance
Banks	$	10,091		3.0
		10,091		3.0
Total Equities:		308,945		91.7
Exchange Traded Fund:		2,470		0.7
Short-Term Obligations:		23,621		7.0
Total Investments:		335,036		99.4
Cash and Other Assets Less Liabilities:		1,901		0.6
Net Assets:	$	336,937		100.0

See accompanying notes to financial statements.

Columbia Acorn Select

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Consumer Goods & Services
Hertz		6,500,000		7,598,000
ITT Educational Services		775,000		825,000
Princeton Review		0		871,636
Steelcase		0		2,017,127
Information
Amphenol		725,000		750,000
Novell		8,000,000		8,500,000
SBA Communications		0		505,000
VisionChina Media - ADR (China)		3,300,000		4,000,000
WNS - ADR (India)		3,800,000		3,937,425
Energy & Minerals
Canadian Solar (China)		1,600,000		1,900,000
Gran Tierra Energy (Canada)		0		2,000,000
Industrial Goods & Services
Donaldson		225,000		250,000
Finance
CIT Group		0		6,000,000
Discover Financial Services		0		1,300,076

	Number of Shares
	03/31/09		06/30/09
Sales
Consumer Goods & Services
Expedia		3,250,000		3,000,000
Knoll		400,000		0
SkillSoft - ADR		9,500,000		9,283,928
Information
American Tower		1,400,000		1,050,000
Discovery Communications		700,000		0
Discovery Communications, Series C		1,250,000		1,125,000
Globalstar		11,000,000		9,800,000
Tellabs		2,800,000		0
Energy & Minerals
Pacific Rubiales Energy (Canada)		8,122,166		7,116,666
Synthesis Energy Systems (China)		2,800,000		2,500,000
Uranium One (South Africa)		18,050,000		9,850,000
Industrial Goods & Services
Expeditors International of Washington		1,425,000		950,000
Quanta Services		2,800,000		2,500,000
Health Care
Cephalon		400,000		0

See accompanying notes to financial statements.

Columbia Acorn Select

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 95.0%
Consumer Goods & Services 33.6%
		> Educational Services 13.5%
	825,000	ITT Educational Services (a)	$	83,044
		Post-secondary Degree Services
	9,283,928	SkillSoft - ADR (a)(b)		72,415
		Web-based Learning Solutions (E-Learning)
	1,700,000	Career Education (a)		42,313
		Post-secondary Education
	871,636	Princeton Review (a)		4,716
		College Preparation Courses
				202,488
		> Travel 7.1%
	7,598,000	Hertz (a)		60,708
		Largest U.S. Rental Car Operator
	3,000,000	Expedia (a)		45,330
		Online Travel Services Company
				106,038
		> Retail 6.0%
	3,350,000	Safeway		68,239
		Supermarkets
	863,000	Abercrombie & Fitch		21,912
		Teen Apparel Retailer
				90,151
		> Apparel 2.9%
	1,600,000	Coach		43,008
		Designer & Retailer of Branded Leather Accessories
				43,008
		> Casinos & Gaming 2.3%
	325,000,000	RexLot Holdings (China) (a)		25,559
		Lottery Equipment Supplier in China
	74,834,052	NagaCorp (Hong Kong)		9,878
		Casino/Entertainment Complex in Cambodia
				35,437
		> Food & Beverage 1.0%
	17,500,000	Fu Ji Food & Catering Services (China)		14,707
		Food Catering Service Provider in China
				14,707
		> Furniture & Textiles 0.8%
	2,017,127	Steelcase		11,739
		Office Furniture
				11,739
Consumer Goods & Services: Total				503,568
Information 19.3%
		> Mobile Communications 6.2%
	1,550,000	Crown Castle International (a)		37,231
		Communications Towers
	1,050,000	American Tower (a)		33,106
		Communications Towers in USA & Latin America
	505,000	SBA Communications (a)		12,393
		Communications Towers
	9,800,000	Globalstar (a)(b)(c)		10,290
		Satellite Mobile Voice & Data Carrier
				93,020

Number of Shares			Value (000)
		> Business Software 2.6%
	8,500,000	Novell (a)	$	38,505
		Directory, Operating System & Identity Management Software
				38,505
		> Computer Services 2.5%
	3,937,425	WNS - ADR (India) (a)(b)		34,965
		Offshore BPO (Business Process Outsourcing) Services
	1,334,442	Hackett Group (a)		3,109
		IT Integration & Best Practice Research
				38,074
		> Advertising 2.5%
	4,000,000	VisionChina Media - ADR (China) (a)(b)		24,440
		Advertising on Digital Screens in China's Mass Transit System
	2,350,000	China Mass Media - ADR (China) (a)(b)		12,173
		Media Planning Agency in China
				36,613
		> Computer Hardware & Related Equipment 1.6%
	750,000	Amphenol		23,730
		Electronic Connectors
				23,730
		> CATV 1.5%
	1,125,000	Discovery Communications, Series C (a)		23,096
		CATV Programming
				23,096
		> Contract Manufacturing 1.5%
	50,200,000	Sanmina-SCI (a)(b)		22,088
		Electronic Manufacturing Services
				22,088
		> Financial Processors 0.9%
	3,700,000	CardTronics (a)(b)		14,097
		Operates the World's Largest Network of ATMs
				14,097
Information: Total				289,223
Energy & Minerals 14.9%
		> Oil & Gas Producers 5.8%
	7,116,666	Pacific Rubiales Energy (Canada) (a)(d)		58,382
	1,483,334	Pacific Rubiales Energy (Canada) (a)		12,230
	2,868,750	Pacific Rubiales Energy-Warrants (Canada) (a)(d)		9,091
		Oil Production & Exploration in Colombia
	2,000,000	Gran Tierra Energy (Canada) (a)		6,964
		Oil Exploration & Production in Colombia, Peru & Argentina
				86,667
		> Oil Services 5.6%
	6,700,000	Tetra Technologies (a)(b)		53,332
		U.S.-based Service Company with Life of Field Approach
	800,000	FMC Technologies (a)		30,064
		Oil & Gas Wellhead Manufacturer
				83,396

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Alternative Energy 2.0%
	1,900,000	Canadian Solar (China) (a)(b)(c)	$	23,028
		Solar Cell & Module Manufacturer
	1,480,000	Real Goods Solar (a)(b)		3,833
		Residential Solar Energy Installer
	2,500,000	Synthesis Energy Systems (China) (a)(b)		2,875
		Owner/Operator of Gasification Plants
				29,736
		> Mining 1.5%
	9,850,000	Uranium One (South Africa) (a)		22,611
		Uranium Mines in Kazakhstan, the U.S. & Australia
				22,611
Energy & Minerals: Total				222,410
Industrial Goods & Services 12.7%
		> Outsourcing Services 3.9%
	2,500,000	Quanta Services (a)		57,825
		Electrical & Telecom Construction Services
				57,825
		> Other Industrial Services 3.1%
	950,000	Expeditors International of Washington		31,673
		International Freight Forwarder
	1,050,000	Mobile Mini (a)		15,403
		Portable Storage Units Leasing
				47,076
		> Waste Management 2.8%
	1,500,000	Waste Management		42,240
		U.S. Garbage Collection & Disposal
				42,240
		> Machinery 1.8%
	525,000	Ametek		18,155
		Aerospace/Industrial Instruments
	250,000	Donaldson		8,660
		Industrial Air Filtration
				26,815
		> Industrial Materials & Specialty Chemicals 1.1%
	1,000,000	Nalco Holding Company		16,840
		Provider of Water Treatment & Process Chemicals & Services
				16,840
Industrial Goods & Services: Total				190,796
Finance 10.7%
		> Brokerage & Money Management 6.6%
	6,015,300	MF Global (a)		35,671
		Futures Broker
	1,300,000	Eaton Vance		34,775
		Specialty Mutual Funds
	1,550,000	SEI Investments		27,962
		Mutual Fund Administration & Investment Management
				98,408

Number of Shares or Principal Amount (000)			Value (000)
		> Insurance 2.4%
	14,950,000	Conseco (a)(b)	$	35,431
		Life, Long-term Care & Medical Supplement Insurance
				35,431
		> Credit Cards 0.9%
	1,300,076	Discover Financial Services		13,352
		Credit Card Company
				13,352
		> Finance Companies 0.8%
	6,000,000	CIT Group		12,900
		Middle Market Lender, Equipment Leasing & Vendor Finance/Factoring
				12,900
Finance: Total				160,091
Other Industries 3.8%
		> Transportation 3.8%
	1,300,000	JB Hunt Transport Services		39,689
		Truck & Intermodal Carrier
	1,125,000	American Commercial Lines (a)(b)(c)		17,415
		Operator of Inland Barges/Builder of Barges & Vessels
				57,104
Other Industries: Total				57,104
Total Equities: 95.0% (Cost: $1,669,978)				1,423,192
Securities Lending Collateral: 1.2%
	17,611,150	Dreyfus Government Cash Management Fund (e) (7 day yield of 0.150%)		17,611
Securities Lending Collateral: Total 1.1% (Cost: $17,611)				17,611
Short-Term Obligations: 5.3%
		> Repurchase Agreement 4.8%
$	72,138	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.0001%, collateralized by a U.S. Government Agency obligation, maturing 3/15/16, market value $73,585 (repurchase proceeds $72,138)		72,138
				72,138

See accompanying notes to financial statements.

Columbia Acorn Select

Statement of Investments (Unaudited), continued

Principal Amount (000)			Value (000)
		> Commercial Paper 0.5%
$	7,700	Toyota Motor Credit 0.26% due 7/06/09	$	7,700
				7,700
Total Short-Term Obligations: 5.3% (Amortized Cost: $79,838)				79,838
Total Investments: 101.5% (Cost: $1,767,427)(f)				1,520,641
Obligation to Return Collateral for Securities Loaned: (1.2)%				(17,611	)
Cash and Other Assets Less Liabilities: (0.3)%				(4,691	)
Total Net Assets: 100.0%			$	1,498,339

ADR = American Depositary Receipts.

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

(a) Non-income producing security.

(b) An affiliated person of the Fund may include any company in which the Fund owns five percent or more of its outstanding voting shares. Transactions in affiliated companies during the six months ended June 30, 2009, are as follows:

Affiliates	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions			Balance of Shares Held 6/30/09		Value		Dividend
American Commercial Lines		3,803,849		696,151		3,375,000	*		1,125,000	$	17,415	$	-
Canadian Solar		1,825,000		300,000		225,000			1,900,000		23,028		-
CardTronics		3,560,000		140,000		-			3,700,000		14,097		-
China Mass Media - ADR		2,350,000		-		-			2,350,000		12,173		-
Conseco		14,950,000		-		-			14,950,000		35,431		-
Globalstar		10,000,000		1,000,000		1,200,000			9,800,000		10,290		-
Real Goods Solar		1,500,000		-		20,000			1,480,000		3,833		-
Sanmina-SCI		50,200,000		-		-			50,200,000		22,088		-
SkillSoft - ADR		9,500,000		-		216,072			9,283,928		72,415		-
Synthesis Energy Systems		2,800,000		-		300,000			2,500,000		2,875		-
Tetra Technologies		6,150,000		1,050,000		500,000			6,700,000		53,332		-
VisionChina Media - ADR		3,118,900		881,100		-			4,000,000		24,440
WNS-ADR		3,100,000		843,500		6,075			3,937,425		34,965		-
Total of Affiliated Transactions		112,857,749		4,910,751		5,842,147			111,926,353	$	326,382	$	-

* Includes the effect of a 1:4 reverse stock split.

The aggregate cost and value of these companies at June 30 were $769,982 and $326,382, respectively. Investments in affiliated companies represented 21.8% of total net assets at June 30, 2009.

(c) All or a portion of this security was on loan at June 30, 2009. The total market value of securities on loan at June 30, 2009 was $16,936.

Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Pacific Rubiales Energy	7/12/07-8/22/07		7,116,666	$	30,391	$	58,382
Pacific Rubiales Energy-Warrants	7/12/07		2,868,750		4,910		9,091
				$	35,301	$	67,473

(e) Investment made with cash collateral received from securities lending activity.

(f) At June 30, 2009, for federal income tax purposes cost of investments was $1,767,427 and net unrealized depreciation was $246,786 consisting of gross unrealized appreciation of $328,086 and gross unrealized depreciation of $574,872.

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Equities
Total Consumer Goods & Services	$	453,424	$	50,144	$	-	$	503,568
Total Information		289,223		-		-		289,223
Total Energy & Minerals		154,937		67,473		-		222,410
Total Industrial Goods & Services		190,796		-		-		190,796
Total Finance		160,091		-		-		160,091
Total Other Industries		57,104		-		-		57,104
Total Equities		1,305,575		117,617		-		1,423,192
Securities Lending Collateral		17,611		-		-		17,611
Short-Term Obligations		-		79,838		-		79,838
Total Investments		1,323,186		197,455		-		1,520,641
Total	$	1,323,186	$	197,455	$	-	$	1,520,641

The Fund's assets assigned to the Level 2 input category include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation.

See accompanying notes to financial statements.

Columbia Thermostat Fund

Statement of Investments (Unaudited), June 30, 2009

Number of Shares or Principal Amount (000)			Value (000)
		> Stock Funds: 99.5%
	3,482,959	Columbia Large Cap Enhanced Core Fund, Class Z	$	31,242
	2,474,587	Columbia Dividend Income Fund, Class Z		24,869
	968,355	Columbia Acorn Fund, Class Z		18,825
	681,187	Columbia Acorn International, Class Z		18,753
	1,323,292	Columbia Marsico Growth Fund, Class Z		18,579
	712,612	Columbia Acorn Select, Class Z		12,471
Total Stock Funds (Cost: $158,610)				124,739
Short-Term Obligations: 0.7%
		> Repurchase Agreements: 0.7%
$	446	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.001%, collateralized by a U.S. Government Agency obligation, maturing 8/20/13 market value $455 (repurchase proceeds $446)		446
	407	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.0001%, collateralized by a U.S. Government Agency obligation, maturing 4/23/14 market value $415 (repurchase proceeds $407)		407
Total Short-Term Obligations (Cost: $853)				853
Total Investments: 100.2% (Cost: $159,463)(a)				125,592
Cash and Other Assets Less Liabilities: (0.2)%				(252	)
Total Net Assets: 100.0%			$	125,340

See accompanying notes to financial statements.

> Notes to Statements of Investments (dollar values in thousands)

(a) At June 30, 2009, for federal income tax purposes cost of investments was $159,463 and net unrealized depreciation was $33,871, consisting of gross unrealized appreciation of $1,670 and gross unrealized depreciation of $35,541.

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Investment Companies	$	124,739	$	-	$	-	$	124,739
Short-Term Obligations		-		853		-		853
Total Investments		124,739		853		-		125,592
Total	$	124,739	$	853	$	-	$	125,592

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Assets and Liabilities (Unaudited)

June 30, 2009	Columbia Acorn Fund			Columbia Acorn International			Columbia Acorn USA			Columbia Acorn International Select			Columbia Acorn Select			Columbia Thermostat Fund
(in thousands)
Assets:
Unaffiliated investments, at cost	$	7,910,206		$	3,004,096		$	1,144,180		$	319,829		$	997,445		$	853
Affiliated investments, at cost (See Note 4)		3,111,124			59,544			16,983			—			769,982			158,610
Unaffiliated investments, at value (including securities on loan: Columbia Acorn Fund $129,784; Columbia Acorn International $1,905; Columbia Acorn USA $23,954; Columbia Acorn International Select $–; Columbia Acorn Select $16,936; Columbia Thermostat Fund $–)	$	9,027,810		$	3,243,462		$	1,105,685		$	335,036		$	1,194,259		$	853
Affiliated investments, at value (See Note 4)		2,822,304			69,240			10,304			—			326,382			124,739
Cash		3,248			1			—			—	*		1			—	*
Foreign currency (cost: Columbia Acorn Fund $4,116; Columbia Acorn International $22,027; Columbia Acorn International Select $335; Columbia Acorn Select $–)		4,174			22,008			—			332			—			—
Net unrealized appreciation on foreign forward currency contracts		—			3,212			—			—			—			—
Receivable for:
Investments sold		26,664			8,714			3,743			1,445			820			—
Fund shares sold		10,208			5,488			1,472			2,199			1,433			141
Dividends and interest		6,441			4,834			447			312			524			—
Securities lending income		197			12			29			—			93			—
Foreign tax reclaims		269			1,679			—			127			—			—
Expense reimbursement due from Advisor		—			—			—			1			—			48
Trustees' Deferred Compensation Investments		2,506			699			193			—			224			—
Other assets		29			9			2			—	*		5			5
Total Assets		11,903,850			3,359,358			1,121,875			339,452			1,523,741			125,786
Liabilities:
Payable to custodian bank		—			—			23			—			—			—
Collateral on securities loaned		133,395			1,944			24,650			—			17,611			—
Expense reimbursement due to Advisor		—			—			—			—			5			—
Net unrealized depreciation on forward foreign currency contracts		—			5,646			—			—			—			—
Payable for:
Investments purchased		28,350			6,876			4,585			1,357			1,870			—
Fund shares redeemed		33,574			4,137			1,388			733			3,615			286
Management fee		6,264			2,119			786			254			1,028			10
Administration fee		432			121			40			12			56			5
12b-1 Service and Distribution fees		1,320			160			65			22			196			45
Reports to shareholders		863			298			92			25			252			41
Deferred Trustees' fees		2,506			699			193			33			224			22
Transfer agent fees		3,057			465			247			29			521			37
Trustees' fees		4			1			1			—	*		4			—	*
Custody fees		287			846			9			33			—			—
Deferred foreign capital gains tax payable		—			2,496			—			—			—			—
Other liabilities		4			48			10			17			20			—
Total Liabilities		210,056			25,856			32,089			2,515			25,402			446
Net Assets	$	11,693,794		$	3,333,502		$	1,089,786		$	336,937		$	1,498,339		$	125,340
Composition of Net Assets:
Paid in capital	$	11,363,927		$	3,696,881		$	1,264,123		$	400,024		$	1,903,392		$	180,354
Undistributed/(overdistributed) net investment income (Accumulated net investment loss)		10,048			28,563			(1,564	)		1,132			(4,758	)		472
Accumulated net realized gain/(loss)		(509,030	)		(636,081	)		(127,599	)		(79,429	)		(153,509	)		(21,615	)
Net unrealized appreciation/(depreciation) on:
Investments		828,784			249,062			(45,174	)		15,207			(246,786	)		(33,871	)
Foreign capital gains tax		—			(2,496	)		—			—			—			—
Foreign currency translations		65			(2,427	)		—			3			—			—
Net Assets	$	11,693,794		$	3,333,502		$	1,089,786		$	336,937		$	1,498,339		$	125,340
Net asset value per share – Class A (a)	$	18.88		$	27.47		$	17.16		$	19.52		$	17.09		$	8.88
(Net assets/shares)		($2,340,341/123,982)			($414,663/15,096)			($144,270/8,409)			($60,654/3,107)			($423,925/24,800)			($38,497/4,335)
Maximum offering price per share – Class A (b)	$	20.03		$	29.14		$	18.21		$	20.71		$	18.14		$	9.42
(Net asset value per share/front- end sales charge)		($18.88/0.9425)			($27.47/0.9425)			($17.16/0.9425)			($19.52/0.9425)			($17.09/0.9425)			($8.88/0.9425)
Net asset value and offering price per share – Class B (a)	$	17.71		$	26.82		$	16.11		$	18.71		$	16.10		$	8.93
(Net assets/shares)		($521,503/29,446)			($37,517/1,399)			($21,287/1,322)			($3,691/197)			($76,156/4,729)			($32,245/3,611)
Net asset value and offering price per share – Class C (a)	$	17.57		$	26.74		$	16.01		$	18.62		$	16.00		$	8.92
(Net assets/shares)		($618,461/35,197)			($65,900/2,465)			($25,641/1,602)			($9,562/513)			($74,894/4,682)			($19,523/2,188)
Net asset value and offering price per share – Class Z (c)	$	19.44		$	27.53		$	17.71		$	19.70		$	17.50		$	8.79
(Net assets/shares)		($8,213,489/422,483)			($2,815,422/102,280)			($898,588/50,731)			($263,030/13,355)			($923,364/52,762)			($35,075/3,989)

(a) Redemption price per share is equal to net asset value less any applicable contingent deferred sales charge and redemption fee.

(b) On sales of $50,000 or more the offering price is reduced.

* Rounds to less than $500.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Operations (Unaudited)
For the Six Months Ended June 30, 2009

(in thousands)	Columbia Acorn Fund			Columbia Acorn International			Columbia Acorn USA			Columbia Acorn International Select			Columbia Acorn Select			Columbia Thermostat Fund
Investment Income:
Dividend income	$	55,015		$	50,215		$	3,987		$	3,849		$	3,540		$	—
Dividend income from affiliates (See Note 4)		8,712			910			—			—			—			—
Dividends from affiliated investment company shares (See Note 4)		—			—			—			—			—			921
Interest income		334			94			19			10			40			—	*
Securitites lending income		197			12			29			—			93			—
		64,258			51,231			4,035			3,859			3,673			921
Foreign taxes withheld		(1,195	)		(4,175	)		(1	)		(328	)		—			—
Total Investment Income		63,063			47,056			4,034			3,531			3,673			921
Expenses:
Management fee		33,835			10,922			4,143			1,225			5,431			60
Administration fee		2,360			629			214			58			297			27
12b-1 Service and Distribution fees:
Class A		2,613			435			163			60			473			46
Class B		1,918			129			78			14			260			119
Class C		2,858			287			118			45			335			100
Transfer agent fees:
Class A		1,250			362			72			35			333			41
Class B		774			74			37			10			141			45
Class C		535			82			22			12			88			26
Class Z		1,833			655			238			44			267			9
Custody fees		487			1,321			22			70			88			—
Trustees' fees		480			130			43			14			64			8
Registration and blue sky fees		79			51			34			37			42			28
Reports to shareholders		1,130			462			171			73			316			82
Chief compliance officer expenses (See Note 4)		290			75			26			7			36			3
Other expenses		457			165			60			42			89			25
Total expenses		50,899			15,779			5,441			1,746			8,260			619
Less custody fees paid indirectly		—	*		—	*		—	*		—	*		—	*		—
Less reimbursement of expenses by Investment Advisor		—			—			—			(5	)		(9	)		(204	)
Net Expenses		50,899			15,779			5,441			1,741			8,251			415
Net Investment Income/(Loss)		12,164			31,277			(1,407	)		1,790			(4,578	)		506
Net Realized and Unrealized Gain (Loss) on Portfolio Positions:
Net realized gain/(loss) on:
Unaffiliated investments		(390,602	)		(254,864	)		(23,665	)		(31,779	)		(38,924	)		—
Affiliated investments (See Note 4)		(952	)		(3,830	)		—			—			(17,425	)		(11,816	)
Foreign currency transactions and forward foreign currency exchange contracts		(163	)		(1,856	)		—			(75	)		488			—
Net realized gain/(loss)		(391,717	)		(260,550	)		(23,665	)		(31,854	)		(55,861	)		(11,816	)
Net change in net unrealized appreciation/(depreciation) on:
Unaffiliated investments		1,098,443			774,311			110,717			61,179			343,493			—
Affiliated investments (See Note 4)		271,729			21,926			(1,892	)		—			6,519			18,571
Foreign currency translations and forward foreign currency exchange contracts		63			971			—			(13	)		(3	)		—
Foreign capital gains tax		—			(2,496	)		—			—			—			—
Net change in unrealized appreciation/ (depreciation)		1,370,235			794,712			108,825			61,166			350,009			18,571
Net realized and unrealized gain		978,518			534,162			85,160			29,312			294,148			6,755
Net Increase in Net Assets resulting from Operations	$	990,682		$	565,439		$	83,753		$	31,102		$	289,570		$	7,261

* Rounds to less than $500.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Changes in Net Assets

	Columbia Acorn Fund						Columbia Acorn International						Columbia Acorn USA
Increase (Decrease) in Net Assets	(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,
(in thousands)	2009			2008			2009			2008			2009			2008
Operations:
Net investment income/(loss)	$	12,164		$	12,367		$	31,277		$	76,400		$	(1,407	)	$	(5,465	)
Net realized gain/(loss) on investments,foreign currency transactions and forward foreign currency exchange contracts		(391,717	)		(11,712	)		(260,550	)		(378,865	)		(23,665	)		(102,173	)
Net realized gain/(loss) on affiliated investments and distributions from affiliated investment company shares		—			—			—			—			—			—
Net change in net unrealized appreciation/(depreciation) on investments, foreign currency translations, forward foreign currency exchange contracts and foreign capital gains tax		1,370,235			(7,343,366	)		794,712			(2,403,090	)		108,825			(495,968	)
Net change in net unrealized appreciation/(depreciation) on affiliated investment company shares		—			—			—			—			—			—
Net Increase/(Decrease) from Operations		990,682			(7,342,711	)		565,439			(2,705,555	)		83,753			(603,606	)
Distributions to Shareholders From:
Net investment income – Class A		—			—			(6,101	)		(1,020	)		—			—
Net realized gain – Class A		—	*		(91,100	)		—			(9,807	)		—			(8,248	)
Net investment income – Class B		—			—			(290	)		—	*		—			—
Net realized gain – Class B		—	*		(26,893	)		—			(1,332	)		—			(1,748	)
Net investment income – Class C		—			—			(348	)		—	*		—			—
Net realized gain – Class C		—			(28,315	)		—			(2,146	)		—			(1,740	)
Net investment income – Class Z		—			(6,088	)		(53,466	)		(23,593	)		—			—
Net realized gain – Class Z		—	*		(284,695	)		—			(68,973	)		—			(41,787	)
Total Distributions to Shareholders		—			(437,091	)		(60,205	)		(106,871	)		—			(53,523	)
Share Transactions:
Subscriptions – Class A		293,596			612,669			59,159			277,346			32,218			53,928
Distributions reinvested – Class A		—	*		83,711			5,737			9,979			—			7,538
Redemptions – Class A		(363,945	)		(1,151,023	)		(77,603	)		(207,715	)		(35,190	)		(69,749	)
Net Increase/(Decrease) – Class A		(70,349	)		(454,643	)		(12,707	)		79,610			(2,972	)		(8,283	)
Subscriptions – Class B		102			1,991			—			1,704			5			71
Distributions reinvested – Class B		—			24,675			278			1,209			—			1,615
Redemptions – Class B		(99,550	)		(255,304	)		(7,739	)		(23,974	)		(3,666	)		(11,765	)
Net Decrease – Class B		(99,448	)		(228,638	)		(7,461	)		(21,061	)		(3,661	)		(10,079	)
Subscriptions – Class C		25,737			62,517			3,110			20,234			957			3,931
Distributions reinvested – Class C		—			22,379			265			1,596			—			1,523
Redemptions – Class C		(76,956	)		(287,537	)		(10,606	)		(43,103	)		(2,805	)		(10,090	)
Net Increase/(Decrease) – Class C		(51,219	)		(202,641	)		(7,231	)		(21,273	)		(1,848	)		(4,636	)
Subscriptions – Class Z		706,723			1,526,416			213,802			664,727			153,038			213,395
Distributions reinvested – Class Z		—			251,789			38,423			64,910			—			37,687
Redemptions – Class Z		(653,809	)		(2,162,613	)		(237,241	)		(912,602	)		(82,920	)		(190,501	)
Net Increase/(Decrease) – Class Z		52,914			(384,408	)		14,984			(182,965	)		70,118			60,581
Net Increase/(Decrease) from Share Transactions		(168,102	)		(1,270,330	)		(12,415	)		(145,689	)		61,637			37,583
Redemption Fees		—			—			116			354			—			—
Total Increase/(Decrease) in Net Assets		822,580			(9,050,132	)		492,935			(2,957,761	)		145,390			(619,546	)
Net Assets:
Beginning of period		10,871,214			19,921,346			2,840,567			5,798,328			944,396			1,563,942
End of period	$	11,693,794		$	10,871,214		$	3,333,502		$	2,840,567		$	1,089,786		$	944,396
Undistributed/(Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)	$	10,048		$	(2,116	)	$	28,563		$	57,491		$	(1,564	)	$	(157	)

* Rounds to less than $500.

See accompanying notes to financial statements.

	Columbia Acorn International Select						Columbia Acorn Select						Columbia Thermostat Fund
Increase (Decrease) in Net Assets	(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,
(in thousands)	2009			2008			2009			2008			2009			2008
Operations:
Net investment income/(loss)	$	1,790		$	2,451		$	(4,578	)	$	(17,307	)	$	506		$	3,146
Net realized gain/(loss) on investments,foreign currency transactions and forward foreign currency exchange contracts		(31,854	)		(46,780	)		(55,861	)		(87,624	)		—			—
Net realized gain/(loss) on affiliated investments and distributions from affiliated investment company shares		—			—			—			—			(11,816	)		(9,015	)
Net change in net unrealized appreciation/(depreciation) on investments, foreign currency translations, forward foreign currency exchange contracts and foreign capital gains tax		61,166			(101,043	)		350,009			(1,330,289	)		—			—
Net change in net unrealized appreciation/(depreciation) on affiliated investment company shares		—			—			—			—			18,571			(58,979	)
Net Increase/(Decrease) from Operations		31,102			(145,372	)		289,570			(1,435,220	)		7,261			(64,848	)
Distributions to Shareholders From:
Net investment income – Class A		(456	)		—			—			—			(7	)		(1,051	)
Net realized gain – Class A		—			(984	)		—			(25,410	)		—			(337	)
Net investment income – Class B		—			—			—			—			—			(657	)
Net realized gain – Class B		—			(189	)		—			(4,641	)		—			(371	)
Net investment income – Class C		—			—			—			—			—			(361	)
Net realized gain – Class C		—			(288	)		—			(4,551	)		—			(201	)
Net investment income – Class Z		(3,077	)		(280	)		—			—			(115	)		(1,140	)
Net realized gain – Class Z		—			(3,600	)		—			(39,523	)		—			(301	)
Total Distributions to Shareholders		(3,533	)		(5,341	)		—			(74,125	)		(122	)		(4,419	)
Share Transactions:
Subscriptions – Class A		21,075			47,637			49,937			131,376			3,418			21,460
Distributions reinvested – Class A		440			901			—			23,381			6			1,269
Redemptions – Class A		(12,187	)		(21,936	)		(103,487	)		(377,780	)		(8,180	)		(14,939	)
Net Increase/(Decrease) – Class A		9,328			26,602			(53,550	)		(223,023	)		(4,756	)		7,790
Subscriptions – Class B		—			271			7			388			—			2,089
Distributions reinvested – Class B		—			170			—			4,147			—			943
Redemptions – Class B		(992	)		(3,345	)		(11,619	)		(41,288	)		(6,281	)		(14,056	)
Net Decrease – Class B		(992	)		(2,904	)		(11,612	)		(36,753	)		(6,281	)		(11,024	)
Subscriptions – Class C		959			7,847			2,400			8,177			807			17,881
Distributions reinvested – Class C		—			248			—			3,639			—			510
Redemptions – Class C		(1,893	)		(4,044	)		(12,442	)		(51,407	)		(6,477	)		(8,717	)
Net Increase/(Decrease) – Class C		(934	)		4,051			(10,042	)		(39,591	)		(5,670	)		9,674
Subscriptions – Class Z		83,230			175,091			126,122			387,091			1,348			23,041
Distributions reinvested – Class Z		833			1,768			—			29,748			106			1,339
Redemptions – Class Z		(29,026	)		(84,177	)		(161,949	)		(373,486	)		(3,619	)		(8,008	)
Net Increase/(Decrease) – Class Z		55,037			92,682			(35,827	)		43,353			(2,165	)		16,372
Net Increase/(Decrease) from Share Transactions		62,439			120,431			(111,031	)		(256,014	)		(18,872	)		22,812
Redemption Fees		23			171			—			—			—			—
Total Increase/(Decrease) in Net Assets		90,031			(30,111	)		178,539			(1,765,359	)		(11,733	)		(46,455	)
Net Assets:
Beginning of period		246,906			277,017			1,319,800			3,085,159			137,073			183,528
End of period	$	336,937		$	246,906		$	1,498,339		$	1,319,800		$	125,340		$	137,073
Undistributed/(Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)	$	1,132		$	2,875		$	(4,758	)	$	(180	)	$	472		$	88

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Changes in Net Assets, continued

	Columbia Acorn Fund						Columbia Acorn International						Columbia Acorn USA
Changes in Shares of Beneficial Interest:	(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,
(in thousands)	2009			2008			2009			2008			2009			2008
Subscriptions – Class A		17,391			26,521			2,525			8,030			2,119			2,597
Shares issued in reinvestment and capital gains – Class A		—			3,428			208			248			—			302
Less shares redeemed – Class A		(22,419	)		(49,918	)		(3,567	)		(6,693	)		(2,303	)		(3,306	)
Net Increase/(Decrease) – Class A		(5,028	)		(19,969	)		(834	)		1,585			(184	)		(407	)
Subscriptions – Class B		5			80			—			44			—	*		3
Shares issued in reinvestment and capital gains – Class B		—			1,065			10			30			—			68
Less shares redeemed – Class B		(6,437	)		(11,645	)		(358	)		(768	)		(256	)		(573	)
Net Decrease – Class B		(6,432	)		(10,500	)		(348	)		(694	)		(256	)		(502	)
Subscriptions – Class C		1,631			3,082			133			569			66			219
Shares issued in reinvestment and capital gains – Class C		—			975			10			41			—			65
Less shares redeemed – Class C		(5,125	)		(13,528	)		(499	)		(1,414	)		(203	)		(514	)
Net Increase/(Decrease) – Class C		(3,494	)		(9,471	)		(356	)		(804	)		(137	)		(230	)
Subscriptions – Class Z		40,996			63,561			8,828			19,040			9,698			9,874
Shares issued in reinvestment and capital gains – Class Z		—			10,170			1,391			1,609			—			1,466
Less shares redeemed – Class Z		(39,033	)		(93,561	)		(10,481	)		(30,912	)		(5,233	)		(8,493	)
Net Increase/(Decrease) – Class Z		1,963			(19,830	)		(262	)		(10,263	)		4,465			2,847
Net Increase/(Decrease) in Shares of Beneficial Interest		(12,991	)		(59,770	)		(1,800	)		(10,176	)		3,888			1,708

* Rounds to less than 500.

See accompanying notes to financial statements.

	Columbia Acorn International Select						Columbia Acorn Select						Columbia Thermostat Fund
Changes in Shares of Beneficial Interest:	(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,
(in thousands)	2009			2008			2009			2008			2009			2008
Subscriptions – Class A		1,214			1,986			3,524			6,192			431			1,952
Shares issued in reinvestment and capital gains – Class A		23			30			—			901			1			147
Less shares redeemed – Class A		(716	)		(959	)		(7,473	)		(18,425	)		(1,067	)		(1,454	)
Net Increase/(Decrease) – Class A		521			1,057			(3,949	)		(11,332	)		(635	)		645
Subscriptions – Class B		—			10			—	*		16			—			176
Shares issued in reinvestment and capital gains – Class B		—			6			—			168			—			104
Less shares redeemed – Class B		(62	)		(149	)		(892	)		(2,059	)		(796	)		(1,344	)
Net Decrease – Class B		(62	)		(133	)		(892	)		(1,875	)		(796	)		(1,064	)
Subscriptions – Class C		58			317			170			469			100			1,558
Shares issued in reinvestment and capital gains – Class C		—			9			—			148			—			56
Less shares redeemed – Class C		(116	)		(183	)		(973	)		(2,581	)		(840	)		(861	)
Net Increase/(Decrease) – Class C		(58	)		143			(803	)		(1,964	)		(740	)		753
Subscriptions – Class Z		4,783			7,667			8,532			17,670			175			1,994
Shares issued in reinvestment and capital gains – Class Z		42			58			—			1,123			12			153
Less shares redeemed – Class Z		(1,706	)		(3,845	)		(11,196	)		(18,669	)		(472	)		(783	)
Net Increase/(Decrease) – Class Z		3,119			3,880			(2,664	)		124			(285	)		1,364
Net Increase/(Decrease) in Shares of Beneficial Interest		3,520			4,947			(8,308	)		(15,047	)		(2,456	)		1,698

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Financial Highlights

Columbia Acorn Fund

Class Z	(Unaudited) Six months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	17.71		$	29.61		$	29.71		$	28.17		$	26.45		$	22.56
Income from Investment Operations
Net investment income (a)		0.04			0.06			0.15	(b)		0.13			0.15			0.04
Net realized and unrealized gain/(loss)		1.69			(11.29	)		2.17			3.92			3.28			4.78
Total from Investment Operations		1.73			(11.23	)		2.32			4.05			3.43			4.82
Less Distributions to Shareholders
From net investment income		—			(0.01	)		(0.12	)		(0.13	)		(0.15	)		(0.02	)
From net realized gains		—			(0.66	)		(2.30	)		(2.38	)		(1.56	)		(0.91	)
Total Distributions to Shareholders		—			(0.67	)		(2.42	)		(2.51	)		(1.71	)		(0.93	)
Net Asset Value, End of Period	$	19.44		$	17.71		$	29.61		$	29.71		$	28.17		$	26.45
Total Return (c)		9.77	%(d)		(38.55	)%		7.69	%(e)(f)		14.45	%(e)		13.11	%(e)		21.51	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		0.80	%(h)		0.76	%		0.74	%		0.74	%		0.74	%		0.81	%
Net investment income (g)		0.41	%(h)		0.26	%		0.46	%		0.45	%		0.57	%		0.18	%
Waiver/Reimbursement		—			—			0.00	%(i)		0.01	%		0.02	%		0.02	%
Portfolio turnover rate		14	%(d)		21	%		20	%		22	%		16	%		20	%
Net assets at end of period (in millions)	$	8,213		$	7,446		$	13,038		$	12,128		$	10,399		$	8,689

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.03 per share.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) Total return includes a voluntary reimbursement by the Advisor for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and $0.01, respectively.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

(i) Rounds to less than 0.01%.

Columbia Acorn International

Class Z	(Unaudited) Six months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	23.13		$	43.60		$	40.31		$	33.44		$	29.03		$	22.66
Income from Investment Operations
Net investment income (a)		0.27			0.60			0.43			0.35			0.34			0.25
Net realized and unrealized gain/(loss)		4.66			(20.26	)		6.56			10.94			5.87			6.37
Total from Investment Operations		4.93			(19.66	)		6.99			11.29			6.21			6.62
Less Distributions to Shareholders
From net investment income		(0.53	)		(0.21	)		(0.34	)		(0.51	)		(0.72	)		(0.25	)
From net realized gains		—			(0.60	)		(3.36	)		(3.91	)		(1.08	)		—
Total Distributions to Shareholders		(0.53	)		(0.81	)		(3.70	)		(4.42	)		(1.80	)		(0.25	)
Redemption Fees
Redemption fees added to paid in capital (a)(b)		—			—			—			—			—			—
Net Asset Value, End of Period	$	27.53		$	23.13		$	43.60		$	40.31		$	33.44		$	29.03
Total Return (c)		21.31	%(d)		(45.89	)%		17.28	%(e)		34.53	%(e)		21.81	%(e)		29.47	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.04	%(g)		0.96	%		0.91	%		0.94	%		0.99	%		1.08	%
Net investment income (f)		2.34	%(g)		1.72	%		0.96	%		0.92	%		1.09	%		1.01	%
Waiver/Reimbursement		—			—			0.00	%(h)		0.01	%		0.02	%		0.02	%
Portfolio turnover rate		20	%(d)		38	%		28	%		31	%		27	%		40	%
Net assets at end of period (in millions)	$	2,815		$	2,372		$	4,918		$	3,836		$	2,629		$	1,919

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Rounds to less than $0.01 per share.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g) Annualized.

(h) Rounds to less than 0.01%.

See accompanying notes to financial statements.

Columbia Acorn USA

Class Z	(Unaudited) Six months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	16.39		$	27.97		$	28.66		$	27.03		$	25.20		$	21.01
Income from Investment Operations
Net investment income/(loss) (a)		(0.02	)		(0.07	)		(0.01	)(b)		(0.02	)		0.07			(0.15	)
Net realized and unrealized gain/(loss)		1.34			(10.55	)		1.03			2.26			3.18			4.48
Total from Investment Operations		1.32			(10.62	)		1.02			2.24			3.25			4.33
Less Distributions to Shareholders
From net investment income		—			—			—			—			(0.05	)		—
From net realized gains		—			(0.96	)		(1.71	)		(0.61	)		(1.37	)		(0.14	)
Total Distributions to Shareholders		—			(0.96	)		(1.71	)		(0.61	)		(1.42	)		(0.14	)
Net Asset Value, End of Period	$	17.71		$	16.39		$	27.97		$	28.66		$	27.03		$	25.20
Total Return (c)		8.05	%(d)		(39.22	)%		3.46	%(e)(f)		8.28	%(f)		12.98	%(f)		20.62	%(f)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		1.06	%(h)		1.01	%		0.98	%		0.98	%		1.01	%		1.09	%
Net investment income/(loss) (g)		(0.21	)%(h)		(0.32	)%		(0.03	)%		(0.07	)%		0.28	%		(0.66	)%
Waiver/Reimbursement		—			—			0.00	%(i)		0.01	%		0.01	%		0.02	%
Portfolio turnover rate		16	%(d)		23	%		21	%		13	%		13	%		18	%
Net assets at end of period (in millions)	$	899		$	758		$	1,214		$	1,214		$	937		$	646

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.09 per share.

(d) Not annualized.

(e) Total return includes a voluntary reimbursement by the Advisor for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by less than 0.01% and less than $0.01, respectively.

(f) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

(i) Rounds to less than 0.01%.

Columbia Acorn International Select

Class Z	(Unaudited) Six months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	18.19		$	32.02		$	27.97		$	20.57		$	18.02		$	14.58
Income from Investment Operations
Net investment income (a)		0.13			0.28			0.14	(b)		0.10			0.13			0.04
Net realized and unrealized gain/(loss)		1.62			(13.53	)		5.96			7.35			2.70			3.47
Total from Investment Operations		1.75			(13.25	)		6.10			7.45			2.83			3.51
Less Distributions to Shareholders
From net investment income		(0.24	)		(0.04	)		(0.28	)		(0.05	)		(0.28	)		(0.07	)
From net realized gains		—			(0.54	)		(1.77	)		—			—			—
Total Distributions to Shareholders		(0.24	)		(0.58	)		(2.05	)		(0.05	)		(0.28	)		(0.07	)
Redemption Fees
Redemption fees added to paid in capital (a)(c)		—			—			—			—			—			—
Net Asset Value, End of Period	$	19.70		$	18.19		$	32.02		$	27.97		$	20.57		$	18.02
Total Return (d)		9.60	%(e)		(42.10	)%		21.86	%(f)		36.27	%(f)		15.98	%(f)		24.14	%(f)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		1.22	%(h)		1.21	%		1.18	%		1.27	%		1.45	%		1.45	%
Net investment income (g)		1.49	%(h)		1.09	%		0.44	%		0.44	%		0.72	%		0.27	%
Waiver/Reimbursement		—			—			0.00	%(i)		0.01	%		0.04	%		0.29	%
Portfolio turnover rate		36	%(e)		68	%		57	%		47	%		39	%		73	%
Net assets at end of period (in millions)	$	263		$	186		$	204		$	129		$	74		$	46

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share reflects special dividends. The effect of these dividends amounted to $0.07 per share.

(d) Total return at net asset value assuming all distributions reinvested.

(e) Not annualized.

(f) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

(i) Rounds to less than 0.01%.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn Select

Class Z	(Unaudited) Six months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	14.07		$	28.41		$	26.59		$	22.77		$	21.13		$	18.20
Income from Investment Operations
Net investment loss (a)		(0.04	)		(0.12	)		(0.07	)		(0.06	)		(0.03	)		(0.10	)
Net realized and unrealized gain/(loss)		3.47			(13.53	)		2.53			4.51			2.35			3.47
Total from Investment Operations		3.43			(13.65	)		2.46			4.45			2.32			3.37
Less Distributions to Shareholders
From net investment income		—			—			—			(0.04	)		—			—
From net realized gains		—			(0.69	)		(0.64	)		(0.59	)		(0.68	)		(0.44	)
Total Distributions to Shareholders		—			(0.69	)		(0.64	)		(0.63	)		(0.68	)		(0.44	)
Net Asset Value, End of Period	$	17.50		$	14.07		$	28.41		$	26.59		$	22.77		$	21.13
Total Return (b)		24.38	%(c)		(49.18	)%(d)		9.20	%(e)		19.68	%(e)		11.08	%(e)		18.58	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.04	%(g)		0.95	%		0.91	%		0.96	%		0.99	%		1.13	%
Net investment loss (f)		(0.47	)%(g)		(0.51	)%		(0.24	)%		(0.26	)%		(0.16	)%		(0.52	)%
Waiver/Reimbursement		—			—			0.00	%(h)		0.02	%		0.03	%		0.02	%
Portfolio turnover rate		9	%(c)		28	%		14	%		21	%		19	%		34	%
Net assets at end of period (in millions)	$	923		$	780		$	1,571		$	909		$	688		$	445

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Total return at net asset value assuming all distributions reinvested.

(d) Total return includes a voluntary reimbursement by the Advisor for a realized investment loss due to a trading error. This reimbursement increased total return and net asset value per share by 0.101% and $0.01, respectively.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g) Annualized.

(h) Rounds to less than 0.01%.

Columbia Thermostat Fund

Class Z	(Unaudited) Six months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	8.19		$	12.26		$	12.57		$	12.50		$	13.12		$	12.31
Income from Investment Operations
Net investment income (a)		0.05			0.24			0.52			0.49			0.43			0.31
Net realized and unrealized gain/(loss)		0.58			(3.96	)		0.53			0.84			0.28			0.82
Total from Investment Operations		0.63			(3.72	)		1.05			1.33			0.71			1.13
Less Distributions to Shareholders
From net investment income		(0.03	)		(0.28	)		(0.57	)		(0.54	)		(0.42	)		(0.29	)
From net realized gains		—			(0.07	)		(0.79	)		(0.72	)		(0.91	)		(0.03	)
Total Distributions to Shareholders		(0.03	)		(0.35	)		(1.36	)		(1.26	)		(1.33	)		(0.32	)
Net Asset Value, End of Period	$	8.79		$	8.19		$	12.26		$	12.57		$	12.50		$	13.12
Total Return (b)(c)		7.67	%(d)		(30.53	)%		8.49	%		10.86	%		5.50	%		9.17	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (e)		0.25	%(f)		0.25	%(g)		0.25	%(g)		0.25	%(g)		0.25	%(g)		0.25	%(g)
Net investment income		1.34	%(f)		2.23	%(g)		4.05	%(g)		3.84	%(g)		3.28	%(g)		2.48	%(g)
Waiver/Reimbursement		0.20	%(f)		0.08	%		0.15	%		0.13	%		0.11	%		0.21	%
Portfolio turnover rate		1	%(d)		130	%		128	%		66	%		96	%		67	%
Net assets at end of period (in millions)	$	35		$	35		$	36		$	31		$	26		$	21

(a) Per share data was calculated using the average shares outstanding during the period. Recognition of net investment income by the Fund is affected by the timing of the declaration of dividends by the underlying investment companies in which the Fund invests.

(b) Total return at net asset value assuming all distributions reinvested.

(c) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(d) Not annualized.

(e) Does not include expenses of the investment companies in which the Fund invests.

(f) Annualized.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited)

1. Nature of Operations

Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat Fund (the "Funds") are each a series of Columbia Acorn Trust (the "Trust"), an open-end management investment company organized as a Massachusetts business trust. The investment objective of each Fund is to seek long-term capital appreciation. Columbia Thermostat Fund pursues its investment objective by investing in shares of other mutual funds. As a "fund of funds" under normal circumstances, the Fund allocates at least 95% of its net assets among a selected group of stock and bond mutual funds ("portfolio funds") according to the current level of the S&P 500 Index in relation to predetermined ranges set by the Adviser. The Fund may invest up to 5% of its net assets plus any cash received that day in cash, repurchase agreements, high quality short-term paper and government securities.

Each Fund may issue an unlimited number of shares. Each Fund currently has four classes of shares: Class A, Class B, Class C and Class Z. Effective February 29, 2008, the Funds no longer offer Class B shares (other than through dividend reinvestment).

Class A shares are sold with a front-end sales charge. Class A shares bought without an initial sales charge in accounts aggregating $1 million up to $50 million at the time of purchase are subject to a 1.00% contingent deferred sales charge ("CDSC") if the shares are redeemed within 12 months of the date of purchase.

Class B shares are subject to a CDSC if redeemed within six years of purchase. Class B shares will convert to Class A shares automatically eight years after purchase.

Class C shares are offered at net asset value but are subject to a CDSC on redemptions made within one year after purchase.

Class Z shares are offered at net asset value. There are certain restrictions on who may purchase Class Z shares. Generally, Class Z shares of a Fund may be exchanged for shares of another fund distributed by Columbia Management Distributors, Inc. at no additional charge.

Columbia Acorn International and Columbia Acorn International Select impose a 2% redemption fee on shares that are redeemed within 60 days or less of purchase. See the discussion of Fund policies regarding the redemption fees in the Funds' prospectuses for more information.

The financial highlights for the Fund's Class A, Class B and Class C shares are presented in a separate semiannual report.

Investment income, realized and unrealized gains and losses, and certain fund-level expenses are allocated pro rata on the basis of the relative net assets of all classes, except that each class bears certain expenses specific to that class such as distribution services, transfer agency, and certain other class specific expenses. Differences in class expenses may result in payment of different dividend distributions for each class. All of the Funds' share classes have equal rights with respect to voting, subject to Fund or class specific matters.

2. Significant Accounting Policies

The preparation of financial statements in accordance with accounting principles generally accepted in the United States of America ("GAAP") requires management to make certain estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Management has evaluated the events and transactions that have occurred through August 20, 2009, the date the financial statements were issued, and noted no items requiring adjustment of the financial statements or additional disclosures. The following is a summary of significant accounting policies consistently followed by the Funds in the preparation of their financial statements.

>Security valuation

Securities of the Funds are valued at market value or, if a market quotation for a security is not readily available or is deemed not to be reliable because of events or circumstances that have occurred between the market quotation and the time as of which the security is to be valued, the security is valued at a fair value determined in good faith under consistently applied procedures established by the Board of Trustees. With respect to Columbia Thermostat Fund, investments in portfolio funds are valued at their net asset value as reported by the portfolio funds. A security traded on a securities exchange or in an over-the-counter market in which transaction prices are reported is valued at the last sales price at the time of valuation. A security traded principally on NASDAQ is valued at the NASDAQ official closing price. A security for which there is no reported sale on the valuation date is valued at the latest bid quotatio n. Short-term investments maturing in 60 days or less are valued at amortized cost, which approximates market value. A security for which a market quotation is not readily available and any other assets are valued at its fair value determined in

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited), continued

good faith under consistently applied procedures established by the Board of Trustees. The Funds have retained an independent statistical fair value pricing service that employs a systematic methodology to assist in the fair valuation process for securities principally traded in a foreign market in order to adjust for possible changes in value that may occur between the close of the foreign exchange and the time as of which the securities are to be valued. If a security is valued at fair value, that value may be different from the last quoted market price for the security.

On January 1, 2008, the Funds adopted Statement of Financial Accounting Standards No. 157, Fair Value Measurements ("SFAS 157"). Under SFAS 157, various inputs are used in determining the value of the Fund's investments. These inputs are summarized in the three broad levels listed below:

• Level 1 – quoted prices in active markets for identical securities

• Level 2 – other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk and others)

• Level 3 – significant unobservable inputs (including management's own assumptions in determining the value of investments)

The inputs or methodologies used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.

Examples of the types of securities in which the Funds would typically invest and how they are classified within this SFAS 157 hierarchy are as follows. Typical Level 1 securities include exchange traded domestic equities, mutual funds whose NAVs are published each day and exchange traded foreign equities that are not statistically fair valued. Typical Level 2 securities include exchange traded foreign equities that are statistically fair valued and short-term investments valued at amortized cost. Typical Level 3 securities include any security fair valued by the Funds' Valuation Committee that relies on significant unobservable inputs.

In April 2009, the Financial Accounting Standards Board ("FASB") issued FASB Staff Position 157-4, Determining Fair Value When the Value and Level of Activity for the Asset or Liability Have Significantly Decreased and Identifying Transactions That Are Not Orderly ("FSP FAS 157-4"), which amends SFAS 157 and is effective for interim and annual periods ending after June 15, 2009. FSP FAS 157-4 provides additional guidance for estimating fair value in accordance with SFAS 157, when the volume and level of activity for the asset or liability measured at fair value has significantly decreased. Additionally, FSP FAS 157-4 expands disclosure requirements for reporting entities with respect to categories of assets and liabilities carried at fair value. Management does not expect the adop tion of FSP FAS 157-4 to have a material impact on the Funds' financial statement disclosure.

>Repurchase agreements

Each Fund may engage in repurchase agreement transactions. Each Fund, through its custodian, receives delivery of underlying securities collateralizing repurchase agreements. The other party is required to maintain collateral that is at all times at least equal to the repurchase price including interest. In the event of default or bankruptcy by the counterparty to the agreement, realization and/or retention of the collateral may be subject to legal proceedings.

>Foreign currency translations

Values of investments denominated in foreign currencies are converted into U.S. dollars using the New York spot market rate of exchange at the time of valuation. Purchases and sales of investments and dividend and interest income are translated into U.S. dollars using the spot market rate of exchange prevailing on the respective dates of such transactions. The gain or loss resulting from changes in foreign exchange rates is included with net realized and unrealized gain or loss from investments, as appropriate.

>Forward foreign currency exchange contracts

Columbia Acorn International may enter into forward foreign currency exchange contracts as an attempt to minimize the risk from adverse changes in the relationship between the U.S. dollar and foreign currencies. A forward foreign currency exchange contract is a commitment to purchase or sell a foreign currency at a future date at a negotiated forward rate. Forward foreign currency exchange contracts are valued at the interpolated forward exchange rate of the underlying currencies and any market gain or loss, arising from the difference between the original value and the current value of such contract, is included as a component of unrealized gain/(loss) on the Statement of Operations. Open forward foreign currency contracts, if any, are disclosed in the Notes to the Statement of Investments. As forward foreign currency contracts are closed the resulting gain or loss, arising from the difference between the original value of the contract and the closing value of such contract, is included as a component of realized gain/(loss) on the Statement of Operations.

A forward foreign currency exchange contract would limit the risk of loss due to a decline in the value of a particular

currency; however, it also would limit any potential gain that might result should the value of the currency increase instead of decrease. These contracts may involve market risk in excess of the unrealized gain or loss reflected on the Statement of Assets and Liabilities. In addition, a Fund could be exposed to counterparty risks if counterparties to the contracts are unable to meet the terms of their contracts. The counterparty risk exposure is, therefore, closely monitored and contracts are only executed with high credit quality financial institutions.

A Fund may use forward contracts to buy or sell a foreign currency when the Advisor believes it has exposure to a foreign currency which may suffer or enjoy a movement against another foreign currency to which the Fund has exposure. A Fund will not attempt to hedge all of its foreign portfolio positions.

On January 1, 2009, the Funds adopted Statement of Financial Accounting Standards No. 161, Disclosures about Derivative Instruments and Hedging Activities – an amendment of FASB Statement No. 133 ("SFAS 161"). SFAS 161 requires additional discussion about the reporting entity's derivative instruments and hedging activities, by providing for qualitative disclosures about the objectives and strategies for using derivatives, quantitative data about the fair value of and gains and losses on derivative contracts, and details of credit-risk-related contingent features in their derivative contracts. For additional information on derivative instruments, please see Note 5.

>Securities lending

Each Fund may lend securities up to one-third of the value of its total assets to certain approved brokers, dealers and other financial institutions to earn additional income. In lending its securities, the Fund retains the benefits of owning the securities, including receipt of dividends or interest generated by the security. The Fund also receives a fee for the loan. The Fund has the ability to recall the loans at any time and could do so in order to vote proxies or to sell the loaned securities. Each loan is collateralized by cash that exceeds the value of the securities on loan. The market value of the loaned securities is determined daily at the close of business of the Fund and any additional required collateral is delivered to the Fund on the next business day. The Fund has elected to invest the cash collateral in the Dreyfus Government Cash Management Fund, and the income earned is paid to the Fund, net of any fees remit ted to Goldman Sachs Agency Lending as the lending agent and net of any borrower rebates. The Funds' advisor, Columbia Wanger Asset Management, L.P. ("CWAM"), does not retain any fees earned by the lending program nor does it charge the Funds for administering the program. Generally, in the event of borrower default, the Fund has the right to use the collateral to offset any losses incurred. In the event the Fund is delayed or prevented from exercising its right to dispose of the collateral, there may be a potential loss to the Fund. Some of these losses may be indemnified by the lending agent. The Fund bears the risk of loss with respect to the investment of collateral.

After suspending securities lending in the third quarter of 2008, the Funds resumed lending securities in the second quarter of 2009. The net lending income earned in 2009 by each Fund is included in the Statement of Operations.

>Security transactions and investment income

Security transactions, investment income and shareholder fund transactions are accounted for on the trade date (date the order to buy or sell is executed) and dividend income and realized gain distributions from other funds are recorded on the ex-dividend date, except that certain dividends from foreign securities are recorded as soon as the information is available to the Funds. Interest income is recorded on the accrual basis and includes amortization of discounts on debt obligations when required for federal income tax purposes. Realized gains and losses from security transactions are recorded on an identified cost basis.

Awards, if any, from class action litigation related to securities owned may be recorded as a reduction of cost of those securities. If the applicable securities are no longer owned, the proceeds are recorded as realized gains.

The Funds estimate the tax character of distributions from real estate investment trusts ("REITs"). Distributions received in excess of income are recorded as a reduction of the cost of the related investments. If the applicable securities are no longer owned, any distributions received in excess of income are recorded as realized gains.

>Restricted securities

Restricted securities are securities that may only be resold upon registration under federal securities laws or in transactions exempt from registration. In some cases, the issuer of restricted securities has agreed to register such securities for resale at the issuer's expense either upon demand by the Funds or in connection with another registered offering of the securities. Many restricted securities may be resold in the secondary market in transactions exempt from registration. Such restricted securities may be determined to be liquid under criteria established by the Board of Trustees.

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited), continued

>Use of estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results may differ from those estimates.

>Fund share valuation

Fund shares are sold and redeemed on a continuing basis at net asset value, subject to any applicable sales charge. Net asset value per share is determined daily as of the close of trading on the New York Stock Exchange ("NYSE") on each day the NYSE is open for trading. Generally, income, expenses and realized and unrealized gain/(losses) of a Fund are allocated to each class proportionately on a daily basis for purposes of determining the net asset value of each class. The Rule 12b-1 service and distribution fees and transfer agency fees are charged to each specific class as expenses are incurred. Redemption fees are accounted for as an addition to paid in capital for purposes of determining the net asset value of each class.

>Custody fees/credits

Custody fees are reduced based on each Fund's cash balances maintained with the custodian. The amount is disclosed as a reduction of total expenses on the Statements of Operations.

>Federal income taxes

The Funds have complied with the provisions of the Internal Revenue Code available to regulated investment companies and, in the manner provided therein, distribute all their taxable income, as well as any net realized gain on sales of investments and foreign currency transactions reportable for federal income tax purposes. Columbia Thermostat Fund distributes all of its taxable income, as well as any net realized gain on sales of portfolio fund shares and any distributions of net realized gains received by the Fund from its portfolio funds, reportable for federal income tax purposes. Accordingly, the Funds paid no federal income taxes and no federal income tax provision was required.

>Foreign capital gains taxes

Realized gains in certain countries may be subject to foreign taxes at the fund level, at rates ranging from approximately 10% to 15%. The Funds accrue for such foreign taxes on net realized and unrealized gains at the appropriate rate for each jurisdiction.

>Distributions to Shareholders

Distributions to shareholders are recorded on the ex-dividend date.

>Indemnification

In the normal course of business, the Trust on behalf of the Funds enters into contracts that contain a variety of representations and warranties and that provide general indemnities. A Fund's maximum exposure under these arrangements is unknown, as this would involve future claims against the Fund. Also, under the Trust's organizational documents, the trustees and officers of the Trust are indemnified against certain liabilities that may arise out of their duties to the Trust. However, based on experience, the Funds expect the risk of loss due to these warranties and indemnities to be minimal.

3. Federal Tax Information

The tax character of distributions paid during the year ended December 31, 2008 was as follows:

	Ordinary Income*		Long-Term Capital Gains
(in thousands)
Columbia Acorn Fund	$	24,585	$	412,506
Columbia Acorn International		32,574		74,297
Columbia Acorn USA		9		53,514
Columbia Acorn International Select		601		4,740
Columbia Acorn Select		—		74,125
Columbia Thermostat Fund		3,595		824

*For tax purposes short-term capital gain distributions, if any, are considered ordinary income distributions.

The following capital loss carryforwards, determined as of December 31, 2008, may be available to reduce taxable income arising from future net realized gains on investments, if any, to the extent permitted by the Internal Revenue Code:

	Year of Expiration
	2009			2010			2011- 2015		2016		Total
(in thousands)
Columbia Acorn Fund	$	—		$	—		$	—	$	—	$	—
Columbia Acorn International		—			—			—		135,487		135,487
Columbia Acorn USA		1,012	*		506	*		—		76,008		77,526
Columbia Acorn International Select		—			—			—		30,442		30,442
Columbia Acorn Select		—			—			—		12,271		12,271
Columbia Thermostat Fund		—			—			—		5,193		5,193

*Of these carryforwards, $1,518 (expiring in 2009 and 2010) remains from Columbia Acorn USA's merger with Stein Roe Small Company Growth Fund on 7/26/2002. Utilization of Stein Roe Small Company Growth Fund's losses could be subject to limitations imposed by the Internal Revenue Code.

Under Financial Accounting Standards Board Interpretation No. 48, Accounting for Uncertainty in Income Taxes – an Interpretation of FASB Statement No. 109 ("FIN 48") management determines whether a tax position of a Fund is more likely than not to be sustained upon examination by the applicable taxing authority, including resolution of any related appeals or litigation processes,

based on the technical merits of the position. The tax benefit to be recognized is measured as the largest amount of benefit that is greater than fifty percent likely of being realized upon ultimate settlement. Management has evaluated the known implications of FIN 48 on its computation of net assets for the Funds. As a result of this evaluation, management believes that FIN 48 does not have any effect on the Fund's financial statements. However, management's conclusions regarding FIN 48 may be subject to review and adjustment at a later date based on factors including, but not limited to, further implementation guidance from FASB, new tax laws, regulations, and administrative interpretations (including relevant court decisions). Each Fund's federal tax returns for the prior three fiscal years remain subject to examination by the Internal Revenue Service. The Funds are not aware of any tax positions for which it is reasonably po ssible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months.

4. Transactions with Affiliates

CWAM is a wholly owned subsidiary of Columbia Management Group, LLC, which in turn is an indirect, wholly owned subsidiary of Bank of America Corporation ("BOA"). CWAM furnishes continuing investment supervision to the Funds and is responsible for the overall management of the Funds' business affairs.

Under the Funds' investment advisory agreements, management fees are accrued daily based on each Fund's average daily net assets and paid monthly to CWAM at the annual rates shown in the table below for each Fund.

Columbia Acorn Fund

Average Daily Net Assets	Annual Fee Rate
Up to $700 million		0.74	%
$700 million to $2 billion		0.69	%
$2 billion to $6 billion		0.64	%
$6 billion and over		0.63	%

Columbia Acorn International

Average Daily Net Assets	Annual Fee Rate
Up to $100 million		1.19	%
$100 million to $500 million		0.94	%
$500 million and over		0.74	%

Columbia Acorn USA

Average Daily Net Assets	Annual Fee Rate
Up to $200 million		0.94	%
$200 million to $500 million		0.89	%
$500 million to $2 billion		0.84	%
$2 billion to $3 billion		0.80	%
$3 billion and over		0.70	%

Columbia Acorn International Select

Average Daily Net Assets	Annual Fee Rate
Up to $500 million		0.94	%
$500 million and over		0.90	%

Columbia Acorn Select

Average Daily Net Assets	Annual Fee Rate
Up to $700 million		0.85	%
$700 million to $2 billion		0.80	%
$2 billion to $3 billion		0.75	%
$3 billion and over		0.70	%

Columbia Thermostat Fund

				Annual Fee Rate
All Average Daily Net Assets					0.10	%

For the six months ended June 30, 2009, the Funds' annualized effective investment advisory fee rates were as follows:

Columbia Acorn Fund	0.65	%
Columbia Acorn International	0.78	%
Columbia Acorn USA	0.88	%
Columbia Acorn International Select	0.94	%
Columbia Acorn Select	0.83	%
Columbia Thermostat Fund	0.10	%

>Expense Limit

CWAM has voluntarily agreed to reimburse the ordinary operating expenses (exclusive of brokerage commissions, interest, taxes and extraordinary expenses, but inclusive of custodian charges relating to overdrafts, if any) after giving effect to any balance credits from the Funds' custodian, exceeding 1.45% annually of the average daily net assets for Columbia Acorn International Select and 1.35% annually of the average daily net assets for Columbia Acorn Select. These arrangements may be modified or terminated by either the Funds or CWAM on 30 days notice.

CWAM has contractually agreed to waive fees and/or reimburse expenses of Columbia Thermostat Fund so that the ordinary operating expenses (exclusive of interest and fees on borrowings, and expenses associated with the Fund's investment in other investment companies, but including custodian charges relating to overdrafts, if any), after giving effect to any balance credits from the Fund's custodian, will not exceed 0.25% annually of the Fund's average daily net assets through April 30, 2010. There is no guarantee that this arrangement will continue thereafter.

Expenses reimbursed by CWAM to Columbia Acorn International Select, Columbia Acorn Select and Columbia

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited), continued

Thermostat Fund for the six months ended June 30, 2009, were $4,468, $8,850 and $203,763, respectively.

CWAM provides administrative services and receives an administration fee from the Funds at the following annual rates:

Columbia Acorn Trust

Aggregate Average Daily Net Assets of the Trust:	Annual Fee Rate
Up to $8 billion		0.050	%
$8 billion to $16 billion		0.040	%
$16 billion to $35 billion		0.030	%
$35 billion to $45 billion		0.025	%
$45 billion and over		0.015	%

For the six months ended June 30, 2009, each Fund's annualized effective administration fee rate was 0.05% of average daily net assets. CWAM has delegated to Columbia Management Advisors, LLC, an indirect, wholly owned subsidiary of BOA, responsibility to provide certain sub-administrative services to the Funds.

Columbia Management Distributors, Inc. ("CMDI"), an indirect, wholly owned subsidiary of BOA, is the Funds' principal underwriter.

Each Fund has adopted a Rule 12b-1 (distribution and service) plan which requires it to pay CMDI a monthly service fee equal to 0.25% annually of the average daily net assets attributable to Class A, Class B and Class C shares and a monthly distribution fee equal to 0.50% and 0.75%, annually, of the average daily net assets attributable to Class B and Class C shares, respectively. CMDI receives no compensation with respect to Class Z shares.

Columbia Management Services, Inc. (the "Transfer Agent"), an indirect, wholly owned subsidiary of BOA, provides shareholder services to the Funds. For such services, each Fund pays the Transfer Agent a monthly fee at the annual rate of $17.00 per open account. The Transfer Agent also receives reimbursement for certain out-of-pocket expenses and sub-transfer agency expenses.

Certain officers and trustees of the Trust are also officers of CWAM. The Trust makes no direct payments to its officers and trustees who are affiliated with CWAM.

The Board of Trustees has appointed a Chief Compliance Officer to the Trust in accordance with federal securities regulations. The Funds, along with other affiliated funds, pay their pro-rata share of the expenses associated with the Office of the Chief Compliance Officer. Those expenses are disclosed separately as "Chief compliance officer expenses" in the Statements of Operations.

The Trust offers a deferred compensation plan for its independent trustees. Under that plan, a trustee may elect to defer all or a portion of his or her compensation. Amounts deferred are retained by the Trust and represent an unfunded obligation of the Trust. The value of amounts deferred is determined by reference to the change in value of Class Z shares of one or more series of the Trust or a money market fund specified by the trustee. Benefits under the deferred compensation plan are payable when the trustee ceases to be a member of the Board of Trustees.

An affiliated person of the Fund may include any company in which the Fund owns five percent or more of its outstanding voting shares. On June 30, 2009, Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA and Columbia Acorn Select each held five percent or more of the outstanding voting securities of one or more companies. Details of investments in those affiliated companies are presented on pages 32, 33, 42, 53 and 65, respectively.

During the six months ended June 30, 2009, the Funds did not engage in purchase and sale transactions with funds that have a common investment advisor (or affiliated investment advisors), common directors/trustees, and/or common officers.

5. Derivative Instruments

Derivatives not accounted for as hedging instruments under Statement 133:

Fair Value of Derivative Instruments for Columbia Acorn International as of June 30, 2009

	Asset			Liability
	Statement of Assets and Liabilities	Fair Value		Statement of Assets and Liabilities	Fair Value
(in thousands)
Forward foreign currency exchange contracts	Unrealized appreciation on forward foreign currency exchange contracts	$	3,212	Unrealized depreciation on forward foreign currency exchange contracts	$	5,646
Total		$	3,212		$	5,646

Columbia Acorn International

Amount of Realized Gain or (Loss) on Derivatives Recognized in Income on the Statement of Operations for the Six Months Ended June 30, 2009

	Forward Foreign Currency Exchange Contracts			Total
(in thousands)
Net realized gain (loss) on foreign currency transactions and forward foreign currency exchange contracts	$	(2,562	)	$	(2,562	)

Change in Unrealized Appreciation or (Depreciation) on Derivatives Recognized in Income on the Statement of Operations for the Six Months Ended June 30, 2009

	Forward Foreign Currency Exchange Contracts		Total
(in thousands)
Net change in unrealized appreciation (depreciation) on foreign currency translations and forward foreign currency exchange contracts	$	845	$	845

6. Borrowing Arrangements

The Trust participates in a $150 million credit facility, which was entered into to facilitate portfolio liquidity. Under the facility, interest is charged to each participating fund based on its borrowings at a rate per annum equal to the higher of Federal Funds Rate or Overnight LIBOR plus 0.75%. In addition, a commitment fee of 0.12% per annum of the unutilized line of credit is accrued and apportioned among the participating funds based on their relative net assets. The commitment fee is included in "Other expenses" in the Statements of Operations. No amounts were borrowed by any Fund under this facility for the six months ended June 30, 2009. The Trust enters into this line of credit for one year durations. The Trust has secured the line of credit for the entire year of 2009.

7. Investment Transactions

The aggregate cost of purchases and proceeds from sales, other than short-term obligations, for the six months ended June 30, 2009, were:

Columbia Acorn Fund

(in thousands)
Investment securities
Purchases	$	1,470,748
Proceeds from sales		1,690,503

Columbia Acorn International

(in thousands)
Investment securities
Purchases	$	527,086
Proceeds from sales		660,319

Columbia Acorn USA

(in thousands)
Investment securities
Purchases	$	215,919
Proceeds from sales		148,557

Columbia Acorn International Select

(in thousands)
Investment securities
Purchases	$	143,633
Proceeds from sales		89,068

Columbia Acorn Select

(in thousands)
Investment securities
Purchases	$	119,281
Proceeds from sales		272,525

Columbia Thermostat Fund

(in thousands)
Investment securities
Purchases	$	831
Proceeds from sales		20,724

8. Redemption Fees

For the six months ended June 30, 2009, the redemption fees imposed by Columbia Acorn International and Columbia Acorn International Select amounted to approximately $116,354 and $22,980, respectively, and are accounted for as additions to paid in capital.

9. Legal Proceedings

The Trust, CWAM and the Trustees of the Trust (collectively, the "Columbia defendants") are named as defendants in class and derivative complaints that have been consolidated in a Multi-District Action (the "MDL Action") in the federal district court of Maryland. These lawsuits contend that defendants permitted certain investors to market time their trades in certain Columbia Acorn Funds. The MDL Action is ongoing. However, all claims against the Trust and the independent trustees of the Trust have been dismissed.

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited), continued

law claims were preempted under federal law resulting in the dismissal of plaintiffs' complaint. Plaintiffs appealed the Seventh Circuit's ruling to the United States Supreme Court. The Supreme Court reversed the Seventh Circuit's ruling on jurisdictional grounds and the case was ultimately remanded to the state court.

On March 21, 2005, a class action complaint was filed against the Trust and CWAM seeking to rescind the CDSC assessed upon redemption of Class B shares of Columbia Acorn Funds due to the alleged market timing of the Columbia Acorn Funds (the "CDSC Lawsuit"). In addition to the rescission of sales charges, plaintiffs seek recovery of actual damages, attorneys' fees and costs. The case had been transferred to the MDL Action in the federal district court of Maryland.

On September 14, 2007, the plaintiffs and the Columbia defendants named in the MDL Action, including the Columbia Funds, entered into a stipulation of settlement with respect to all Columbia-related claims in the MDL Action described above, including the CDSC and Fair Valuation Lawsuits. The settlement is subject to court approval.

Columbia Acorn Trust and CWAM intend to defend these suits vigorously. CWAM believes that the lawsuits are not likely to materially affect its ability to provide investment management services to the Funds.

[Excerpt from:]

Columbia Acorn Trust

Management Fee Evaluation of the Senior Officer

Prepared Pursuant to the New York Attorney General's
Assurance of Discontinuance

May 2009

Introduction

The New York Attorney General's Assurance of Discontinuance ("Order") entered into by Columbia Management Advisors, Inc. ("CMAI") and Columbia Management Distributors, Inc., ("CMDI" and collectively with "CMAI," "CMG") in February 2005, allows CMAI to manage or advise a mutual fund only if the trustees of the fund appoint a "Senior Officer" to perform specified duties and responsibilities. One of these responsibilities includes "managing the process by which proposed management fees (including but not limited to, advisory fees) to be charged the [Funds] are negotiated so that they are negotiated in a manner which is at arms' length and reasonable and consistent with this Assurance of Discontinuance."

This is the third year that the Columbia Acorn Trust and Wanger Advisors Trust (collectively, the "Trusts") and each series thereof (the "Acorn funds," "WAT funds" or collectively, the "Funds") have been overseen by the same Board of Trustees ("Board"). The Order provides that this Board must determine the reasonableness of proposed "management fees" by using either an annual competitive bidding process supervised by the Senior Officer or Independent Fee Consultant, or by obtaining "an annual independent written evaluation prepared by or under the direction of the Senior Officer or the Independent Fee Consultant."

"Management fees" are only part of the costs and expenses paid by mutual fund shareholders. Fund expenses can vary depending upon the class of shares held but usually include: (1) investment management or advisory fees to compensate analysts and portfolio managers for stock research and portfolio management, as well as the cost of operating a trading desk; (2) administrative expenses incurred to prepare registration statements and tax returns, calculate the Funds' net asset values, maintain effective compliance procedures and perform recordkeeping services; (3) transfer agency costs for establishing accounts, accepting and disbursing funds, as well as overseeing trading in Fund shares; (4) custodial expenses incurred to hold the securities purchased by the Funds; and (5) distribution expenses, including commissions paid to brokers that sell the Fund shares to investors.

Columbia Wanger Asset Management, L.P. ("CWAM"), the adviser to the Funds, has proposed that the Trusts continue the existing separate agreements governing the first two categories listed above: an advisory agreement governing portfolio management, and an administration agreement governing certain administration and clerical services. Together the fees paid under these two agreements are referred to as "management fees." Other fund expenses are governed by separate agreements, in particular agreements with two CWAM affiliates: CMDI, the broker-dealer that underwrites and distributes the Funds' shares, and Columbia Management Services, Inc. ("CMSI"), the Funds' transfer agent. In conformity with the terms of the Order, this evaluation, therefore, addresses only the advisory and administrative contracts, and does not extend to the other agreements.

According to the Order, the Senior Officer's evaluation must consider at least the following:

(1) Management fees (including components thereof) charged to institutional and other clients of CWAM for like services;

(2) Management fees (including any components thereof) charged by other mutual fund companies for like services;

(3) Costs to CWAM and its affiliates of supplying services pursuant to the management fee agreements, excluding any intra-corporate profit;

(4) Profit margins of CWAM and its affiliates from supplying such services;

(5) Possible economies of scale as the Funds grow larger; and

(6) The nature and quality of CWAM's services, including the performance of each Fund.

In 2004, the Boards of the two Trusts, then separate groups, each appointed me Senior Officer under the Order. They also determined not to pursue a competitive bidding process and instead, charged me with the responsibility of evaluating the Funds' proposed advisory and administrative fee contracts with CWAM in conformity with the requirements of the Order. This Report is an annual evaluation required under the Order. In discharging their responsibilities, the independent Trustees have also consulted independent, outside counsel.

2008 Evaluation

This is the fourth annual evaluation prepared in connection with the Order. This evaluation follows the same structure as the earlier studies. Some areas are given more emphasis here, while others are given less. Still, the fundamental information gathered for this evaluation is largely the same as past years. Last year's evaluation is referred to here as the "2008 Study."

Process and Independence

The objectives of the Order are to ensure the independent evaluation of the management fees paid by the Funds as well as to insure that all relevant factors are considered. In my view, this contract renewal process has been conducted at arms-length and with independence in gathering, considering and evaluating all relevant data. At the outset of the process, the Trustees sought and obtained from CWAM and CMG a comprehensive compilation of data regarding Fund performance and expenses, adviser profitability, and other information. The Contract Committee evaluated this information thoroughly. Performance and expense data was obtained from both Morningstar and Lipper, the leading consultants in this area. The rankings prepared by Morningstar and Lipper were independent and not influenced by the adviser.

In the course of its work, the Contract Committee gave careful consideration to the conclusions and recommendations contained in the 2008 Study. The Committee recommended, and the Board accepted and implemented several of the recommendations in this area contained in the 2008 Study.

My evaluation of the advisory contracts was shaped, as it was last year, by my experience as Chief Compliance Officer of the Trusts ("CCO"). As CCO, I report solely to the Board and have no reporting obligation to, or employment relationship with, CMG or its affiliates, except for administrative purposes. I have commented on compliance matters in evaluating the quality of service provided by CWAM.

This Report, its supporting materials and the data contained in other materials submitted to the Contract Committee of the Board, in my view, provide a thorough factual basis upon which the Board, in consultation with independent counsel as it deems appropriate, may conduct management fee negotiations that are in the best interests of the Funds' shareholders.

The Fee Reductions Mandated under the Order

Under the terms of the Order, CMG agreed to secure certain management fee reductions for the mutual funds advised by its affiliate investment advisers. In some instances, breakpoints were also established. Although neither CWAM nor the Trusts was a party to the Order, CWAM offered and the Board accepted certain advisory fee reductions during 2005. By the terms of the Order, these fees may not be increased before November 30, 2009. I have used these advisory fee levels, as modified thereafter, in this evaluation because they are the fees in the current agreements that CWAM proposes should be continued. Hence, these fee levels are the starting point of an evaluation.

Conclusions

My review of the data and other material above leads to the following conclusions with respect to the factors identified in the Order.

1. Performance. The Acorn Fund has achieved good to outstanding performance over the past five years. Acorn Select and Acorn USA have, however, suffered significant declines in ranking relative to their peers for the past five years. The three year rankings for Acorn Select and Acorn USA are also well below medians. In contrast, the international Acorn funds have improved their relative performance and enjoy solid rankings.

2. Management Fees relative to Peers. The management fee rankings for several of the Acorn funds are generally more favorable to shareholders than those of their peer group funds. Management fees do, however, vary by Fund. Acorn Fund and Acorn International are the most competitive, while Acorn Select and Acorn USA are the least competitive in the assessments prepared by both Morningstar and Lipper.

3. Administrative Fees. The Acorn funds' administrative fees are generally less competitive than are the fees charged by competitors, but these rankings suffer from a lack of uniformity in the scope of services encompassed by the fee. CWAM provides excellent administrative support for all the Funds. There are clear advantages to retaining the adviser and its affiliates to perform these services.

4. Management Fees relative to Institutional and Other Mutual Fund Accounts. CWAM's focus is on its mutual funds. It does not actively seek to manage separate or institutional accounts. The few institutional accounts it does manage vary in rate structures. Some pay advisory fees commensurate with or higher than the Acorn funds. In a few instances, however, institutional accounts pay lower advisory fees than do the Acorn funds. One particular institutional account is significant in size and has been under CWAM's management for over 31 years.

5. Costs to CWAM and its Affiliates. CWAM's direct costs do not appear excessive. Overhead and indirect costs allocated to CWAM by its parent organizations, however, are significant and have varied considerably over the years. CWAM's affiliates report operating losses and therefore do not appear to enjoy excessive "fall out" benefits from CWAM's advisory agreement with the Funds.

6. Profit Margins. CWAM's pre-marketing expense profit margins are at the top of the industry, even in a difficult year such as 2008, though these comparisons are hampered by limited industry data. High profit margins are not unexpected for firms that manage large, successful funds and have provided outstanding investment performance for investors.

7. Economies of Scale. Economies of scale do exist at CWAM and will continue if asset levels return to those of past years. The Board has recently imposed additional breakpoints for some of the Funds that will result in greater sharing of economies of scale.

8. Nature and Quality of Services. This category includes a variety of considerations that are difficult to quantify, yet can have a significant bearing on the performance of the Acorn funds. Several areas merit comment.

a. Capacity. CWAM has maintained its investment management capacity even in a difficult environment.

b. Compliance. CWAM has a reasonably designed compliance program that protects shareholders.

9. Process. In my opinion, the process of negotiating an advisory contract for the Acorn funds has been conducted thoroughly and at arms' length. Further, the Trustees have sufficient information to evaluate management's proposal, and negotiate contract terms that are in the best interests of Fund shareholders.

Recommendations

I believe the Trustees should:

1. Monitor closely the performance of Acorn Select and Acorn USA to ensure that appropriate steps are being taken by CWAM to improve their relative performance.

2. Consider imposing limitations on the use of soft dollars. While CWAM's use of soft dollars is consistent with the applicable regulatory requirements, the Board should have a clear understanding with CWAM regarding the cost to shareholders of the research purchased with Fund commission dollars.

3. Seek assurances that CWAM and its affiliates will continue to provide adequate support to the Acorn funds despite the recent downturn in market values and the difficulties faced by CWAM's ultimate parent organization, Bank of America. Similar assurances should be sought from any prospective purchaser of CWAM or its parent organization.

Robert P. Scales

May 26, 2009

Board Approval of the Advisory Agreement

Columbia Acorn Trust (the "Trust") has an investment advisory agreement (the "Advisory agreement") with Columbia Wanger Asset Management, L.P. ("CWAM") under which CWAM manages the Columbia Acorn Funds (the "Funds"). The trustees of the Trust, more than seventy five percent of whom have never been affiliated with CWAM (the "Independent Trustees"), oversee the management of each Fund and, as required by law, determine at least annually whether to continue the Advisory Agreement for each Fund.

The Contract Committee of the board of trustees (the "Committee"), which is comprised of seven Independent Trustees, makes recommendations to the board regarding any proposed continuation of the Advisory agreement. After the Committee has made its recommendations, the full board of trustees determines whether to approve continuation of the Advisory Agreement. The board also considers matters bearing on the Advisory Agreement at its various meetings throughout the year, and meets at least quarterly with CWAM's portfolio managers.

In connection with their most recent consideration of the Advisory Agreement for each Fund, the Committee and all trustees received and reviewed a substantial amount of information provided by CWAM in response to requests from the Independent Trustees and their independent legal counsel. In addition, the Contract committee met with the Investment Performance Committee, also comprised exclusively of Independent Trustees, to review performance-related issues. As they considered the Advisory Agreement, the Independent Trustees were advised by independent legal counsel. At each meeting where the Committee or the Independent Trustees considered the Advisory Agreement, they met with management and also met in separate executive session with their independent legal counsel.

The materials reviewed by the Committee and the trustees included, among other items, (i) information on the investment performance of each Fund and its peer groups and performance benchmarks, (ii) information on each Fund's advisory fees and other expenses, including information comparing the Fund's fees and expenses to those of peer groups of funds and information about any applicable expense limitations and fee "breakpoints," (iii) data on sales and redemptions of Fund shares and (iv) information on the profitability to CWAM, as well as potential "fall-out" or ancillary benefits that CWAM and its affiliates may receive as a result of their relationships with the Funds. The trustees also considered other information such as (i) CWAM's financial condition, (ii) each Fund's investment objective and strategies, (iii) the size, education and experience of CWAM's investment staff and its use of technology, external research and tra ding cost measurement tools, (iv) the allocation of the funds' brokerage, if any, including allocations to brokers affiliated with CWAM, and the use of "soft" commission dollars to pay for research products and services, (v) the resources devoted to, and the record of compliance with, the Funds' investment policies and restrictions, policies on personal securities transactions and other compliance policies and (vi) the economic and market outlook generally and for the mutual fund industry in particular and, including, the market-related events in 2008. In addition, the trustees conferred with, and reviewed the Management Fee Evaluation (the "Fee Evaluation") prepared by the Trust's chief compliance officer, who also serves as the Trust's "Senior Officer," as contemplated by the Assurance of Discontinuance dated February 9, 2005 among affiliates of CWAM and the Office of the New York Attorney General. A summary of the Fee evaluation is included in this report. Throughout the annual contract renewal process, t he trustees had the opportunity to ask questions of and request additional materials from CWAM.

The Committee held meetings in May 2009 and reported its recommendations to the full board of trustees. On June 10, 2009, the board of trustees unanimously approved continuation through July 31, 2010 of (i) the Advisory Agreement and (ii) the Trust's administrative services agreement with CWAM (the "Administration Agreement").

In considering the continuation of the Advisory Agreement and the continuation of the amended administration agreement, the trustees reviewed and analyzed various factors that they determined were relevant, including the factors described below, none of which by itself was considered dispositive. However, the material factors and conclusions that formed the basis for the trustees' determination to approve the continuation of the Advisory Agreement and the amended Administration Agreement are discussed separately below.

Nature, quality and extent of services. The trustees reviewed the nature, quality and extent of the services of CWAM and its affiliates to the Funds, taking into account the investment objective and strategy of each Fund and knowledge gained from meetings with management, which were held on at least a quarterly basis. In addition, the trustees reviewed the available resources and key personnel of CWAM and its affiliates, especially those providing investment management services to the Funds. The trustees also considered other services provided to the Funds by CWAM and its affiliates, including: managing the execution of portfolio transactions and selecting broker-dealers for those transactions; monitoring adherence to the Funds' investment restrictions; producing shareholder reports; providing

support services for the board of trustees and committees of the board; communicating with shareholders; serving as the funds' administrator; and overseeing the activities of the Funds' other service providers, including monitoring for compliance with various policies and procedures as well as applicable securities laws and regulations.

The trustees concluded that the nature, quality and extent of the services provided by CWAM and its affiliates to each Fund were appropriate and consistent with the terms of the Advisory Agreement and the Administration Agreement, and that the quality of those services had been consistent with or superior to quality norms in the industry. The trustees further concluded that the Funds were likely to benefit from the continued provision of those services by CWAM to the Funds. They also concluded that CWAM currently had sufficient personnel, with appropriate education and experience, to serve the Funds effectively, and had demonstrated its continuing ability to attract and retain well qualified personnel.

Performance of the Funds. At various meetings of the board of trustees, the Committee and the Investment Performance Committee of the board, the trustees considered the short-term and longer-term performance of each Fund. They reviewed information comparing each Fund's performance with that of its benchmark(s) and with the performance of comparable funds and peer groups as identified by Lipper Inc. ("Lipper") and Morningstar, Inc. ("Morningstar"). The trustees discussed how the Acorn Fund had outperformed its peers and primary benchmark for the five year period, according to Morningstar, noting that Lipper's ranking of the Fund was somewhat lower than Morningstar's. The trustees considered that the Fund was able to achieve this level of outperformance while experiencing less risk than competing funds, according to Morningstar. Each of Columbia Acorn S elect and Columbia Acorn USA had a particularly difficult performance year during 2008, which the trustees acknowledged. For the five-year period, Acorn USA outperformed its peer group but not its primary benchmark. Columbia Acorn Select's five-year performance was below that of its peer group average and primary benchmark. Focusing on Columbia Thermostat Fund, the trustees noted the Fund had underperformed against its benchmarks and peers over the past five years, according to Lipper and Morningstar rankings. The trustees also reviewed the performance of the international Funds, discussing how both had improved their relative performance from the prior year, and that each continued to beat its benchmark and peer group averages over the five-year period. In evaluating the underperforming funds, the trustees considered that CWAM had provided them with substantial amounts of additional performance information and had committed to take certain steps to improve performance, which the trustees would monitor. Duri ng the annual contract renewal process, the trustees concluded that, although past performance is not necessarily indicative of future results, the strong overall longer-term performance record of most of the Funds was an important factor in the their evaluation of the quality of services provided by CWAM under the Advisory Agreement.

Costs of Services and Profits Realized by CWAM. At various Committee and board of trustees meetings and other informal meetings, the trustees examined detailed information on the fees and expenses of each Fund in comparison to information for other comparable funds provided by Lipper and Morningstar. As noted in the Fee Evaluation, the contractual rates of investment advisory fees and the actual advisory fees paid by Columbia Acorn Select, Columbia Acorn International Select and Columbia Acorn USA were higher than the median advisory fee rates of each Fund's respective peer group. The trustees also considered the advisory fees of the Funds relative to those of the series of Wanger Advisors Trust ("Wanger"), a group of funds with similar investment strategies also overseen by the trustees and managed by CWAM. The trustees noted that the funds' advisory fees were comparable to those of the Wanger funds.

The trustees reviewed the analysis of the profitability of CWAM in serving as each Fund's investment adviser and of CWAM and its affiliates in their relationships with each Fund, as well as an explanation of the methodology utilized in allocating various expenses among the Funds and other business units, each of which was included in the Fee Evaluation. The trustees considered the methodology used by CWAM in determining compensation payable to portfolio managers and the competitive market for investment management talent. They discussed how profitability comparisons among fund managers are not very meaningful due to the small number of publicly-owned managers, and how the profitability of any investment manager is affected by numerous factors, including its particular organizational structure, the types of funds and other accounts managed, other lines of business, expense allocation methodology, capital structure and cost of cap ital.

The trustees also reviewed the advisory fees charged by CWAM for managing other investment companies, sub-advised funds and other institutional separate accounts, as detailed in the Fee Evaluation. CWAM's institutional separate account fees for various investment strategies were examined and in some cases those fees were higher than the advisory fees charged to

Board Approval of the Advisory Agreement, continued

the Funds, and in some instances the Funds' fees were higher. The trustees noted that CWAM performs significant additional services for the Funds that it does not provide to sub-advised funds or non-mutual fund clients, including administrative services, oversight of the Funds' other service providers, trustee support, regulatory compliance and numerous other services, and that, in servicing the Funds, CWAM assumes many legal risks that it does not assume in servicing many of its other clients. Finally, as part of the annual contract renewal process, the trustees considered CWAM's financial condition as a result of market-related declines in assets in 2008 and 2009, and the possible impending sale of Bank of America's controlling interest in CWAM.

The trustees concluded that the rates of advisory fees and other compensation payable by the funds to CWAM and its affiliates were reasonable in relation to the nature and quality of the services to be provided, taking into account the fees charged by other advisers for managing comparable mutual funds with similar strategies and the fees CWAM charges to other clients. The trustees also concluded that the Funds' estimated overall expense ratios were reasonable, considering the quality of services provided by CWAM and its affiliates and the investment performance of the Funds.

Economies of Scale. At various meetings throughout the annual contract renewal process, the trustees considered information about the extent to which CWAM realizes economies of scale in connection with the increase of Fund assets. The trustees noted that the advisory fee schedule for each Fund, other than Columbia Thermostat Fund, which is relatively modest in size, includes breakpoints in the rate of fees at various asset levels. They noted that the Funds also share directly in economies of scale through lower charges by third party service providers based on the combined scale of all of the Funds. The trustees concluded that the current fee structure of each Fund was reasonable and reflective of a sharing between CWAM and the Funds of economies of scale.

Other Benefits to CWAM. The trustees also reviewed benefits that accrue to CWAM and its affiliates from their relationships with the Funds, as outlined in the Fee Evaluation. They noted that the Funds' transfer agent and distributor were each affiliates of CWAM and that the transfer agent received compensation from the Funds for services provided, and that Columbia Management Distributors, Inc. ("CMD"), the Funds' distributor, received Rule 12b-1 fees, most of which CMD paid to broker-dealers. The trustees considered ways, other than the services provided by CWAM and its affiliates pursuant to various agreements and the fees to be paid by each Fund therefor, that the Funds and CWAM may potentially benefit from their relationship with each other. At various Committee meetings, the trustees also considered CWAM's use of commissions paid by each Fund on its portfolio brokerage transactions to obtain research products and services benefiting the Fund and/or other clients of CWAM. They determined that CWAM's use of the Funds' "soft" commission dollars to obtain research products and services was consistent with regulatory requirements and guidance then in effect. They also concluded that CWAM benefits from the receipt of proprietary research products and services acquired through commissions paid on portfolio transactions of the Funds, and that the Funds benefit from CWAM's receipt of those products and services as well as research products and services acquired through commissions paid by other clients of CWAM. The trustees further determined that the success of any Fund could attract other business to CWAM or the Funds and that the success of CWAM could enhance its ability to serve the Funds.

After full consideration of the above factors, as well as other factors that were instructive in evaluating the Advisory Agreement, the trustees, including the Independent Trustees, concluded that the continuation of the Advisory Agreement and continuation of the Administration Agreement was in the best interest of each Fund. On June 10, 2009, the trustees approved continuation of the Advisory Agreement and the Administration Agreement, as amended, through July 31, 2010.

Columbia Acorn Family of Funds

Second Quarter Class Z Share Information

Minimum Initial Investment in
all Funds				$2,500
				$1,000 for an IRA
Minimum Subsequent
Investment in all Funds				$50
Exchange Fee				None

Columbia Acorn Fund	ACRNX
Management Fee	0.65	%
12b-1 Fee	None
Other Expenses	0.15	%
Net Expense Ratio	0.80	%
Columbia Acorn International	ACINX
Management Fee	0.78	%
12b-1 Fee	None
Other Expenses	0.26	%
Net Expense Ratio	1.04	%
Columbia Acorn USA	AUSAX
Management Fee	0.88	%
12b-1 Fee	None
Other Expenses	0.18	%
Net Expense Ratio	1.06	%
Columbia Acorn International Select	ACFFX
Management Fee	0.94	%
12b-1 Fee	None
Other Expenses	0.28	%
Net Expense Ratio	1.22	%
Columbia Acorn Select	ACTWX
Management Fee	0.83	%
12b-1 Fee	None
Other Expenses	0.21	%
Net Expense Ratio	1.04	%
Columbia Thermostat Fund	COTZX
Management Fee	0.10	%
12b-1 Fee	None
Other Expenses	0.15	%*
Net Expense Ratio	0.25	%

Fees and expenses are for the six months ended June 30, 2009, and for Columbia Thermostat Fund include the effect of CWAM's undertaking to waive fees and/or reimburse the Fund for any ordinary operating expenses (exclusive of interest and fees on borrowings, and expenses associated with the Fund's investment in other investment companies, but inclusive of custodian charges relating to overdrafts, if any), after giving effect to any balance credits from the Fund's custodian in excess of the annual rate of 0.25% of the average daily net assets. Columbia Thermostat Fund's reimbursement arrangement is contractual through April 30, 2010.

* Does not include estimated fees and expenses of 0.78% incurred by the Fund from the underlying portfolio funds in which it invests.

Columbia Acorn Family of Funds

Trustees

Robert E. Nason

Chairman of the Board*

Allan B. Muchin

Vice Chairman of the Board

Laura M. Born

Michelle L. Collins

Maureen M. Culhane

Margaret M. Eisen

Jerome Kahn, Jr.

Steven N. Kaplan

David C. Kleinman

Charles P. McQuaid

James A. Star

Ralph Wanger

John A. Wing

Officers

Charles P. McQuaid

President

Ben Andrews

Vice President

Michael G. Clarke

Assistant Treasurer

Jeffrey R. Coleman

Assistant Treasurer

P. Zachary Egan

Vice President

Peter T. Fariel

Assistant Secretary

John M. Kunka

Assistant Treasurer

Joseph C. LaPalm

Vice President

Bruce H. Lauer

Vice President, Secretary and Treasurer

Louis J. Mendes III

Vice President

Robert A. Mohn

Vice President

Christopher J. Olson

Vice President

Robert P. Scales

Chief Compliance Officer, Chief Legal Officer,
Senior Vice President and General Counsel

Linda K. Roth-Wiszowaty

Assistant Secretary

* Deceased, June 27, 2009.

Investment Advisor

Columbia Wanger Asset Management, L.P.
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606

1-800-922-6769

Distributor

Columbia Management Distributors, Inc.
One Financial Center
Boston, Massachusetts 02111-2621

Transfer Agent, Dividend Disbursing Agent

Columbia Management Services, Inc.
P. O. Box 8081
Boston, Massachusetts 02266-8081

1-800-345-6611

Legal Counsel to the Funds

K&L Gates LLP
Washington, DC

Legal Counsel to the Independent Trustees

Drinker Biddle & Reath LLP
Philadelphia, Pennsylvania

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP
Chicago, Illinois

This report, including the schedules of investments, is submitted for the general information of the shareholders of Columbia Acorn Trust.

A description of the policies and procedures that the Funds use to determine how to vote proxies and a copy of the Funds' voting record are available (i) without charge, upon request, by calling 800-922-6769 and (ii) on the Securities and Exchange Commission's website at www.sec.gov. Information regarding how the Funds voted proxies relating to portfolio securities during the 12-month period ended June 30, 2009, is available from the SEC's website. Information regarding how the Funds voted proxies relating to portfolio securities is also available at http://institutional.columbiamanagement.com.

The Funds file a complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year on Form N-Q. The Funds' Form N-Q is available on the SEC's website at www.sec.gov and may be reviewed and copied at the SEC's Public Reference Room in Washington, D.C. Information on the operation of the Public Reference Room may be obtained by calling 1-800-SEC-0330.

Please read and consider the investment objectives, risks, charges and expenses for any fund carefully before investing. For a prospectus which contains this and other important information about the Fund, contact your Columbia Management representative or financial advisor or go to www.columbiamanagement.com.

Columbia Management Group, LLC ("Columbia Management") is the investment management division of Bank of America Corporation. Columbia Management entities furnish investment management services and products for institutional and individual investors. Columbia Funds are distributed by Columbia Management Distributors, Inc., member of FINRA, SIPC, part of Columbia Management and an affiliate of Bank of America Corporation.

Columbia Wanger Asset Management, L.P. ("CWAM") is a registered investment advisor and an indirect, wholly owned subsidiary of Bank of America Corporation. CWAM is part of Columbia Management.

Find out what's new – visit our web site at:

www.columbiafunds.com

Our e-mail address is:

ServiceInquiries@ColumbiaManagement.com

Shareholders should not include personal information such as account numbers, Social Security numbers or taxpayer identification numbers in e-mail. We are unable to accept account transactions sent via e-mail.

Columbia Management^®

Columbia Acorn Family of Funds

Class Z Shares

Semiannual Report, June 30, 2009

For More Information

You'll find more information about the Columbia Acorn Family Funds in the documents described below. Contact Columbia Funds as follows to obtain these documents free of charge:

By Mail: Columbia Funds
c/o Columbia Management Services, Inc.
P.O. Box 8081
Boston, MA 02266-8081

By Telephone: 800.345.6611

Online: www.columbiafunds.com

Shareholder Communications with the Board

The Funds' Board of Trustees has adopted procedures by which shareholders may communicate with the Board. Shareholders who wish to communicate with the Board should send their written communications to the Board by mail, c/o Columbia Wanger Asset Management, L.P., 227 West Monroe Street, Suite 3000, Chicago, Illinois 60606, Attention: Secretary. Shareholder communications must (i) be in writing, (ii) identify the Columbia Acorn Fund to which the communication relates and (iii) state the particular class of shares and number of shares held by the communicating shareholder.

Prospectuses and the Statement of Additional Information (SAI)

The prospectuses and the SAI provide more detailed information about the Funds and their policies. The SAI is legally part of each prospectus (it's incorporated by reference). A copy of each has been filed with the SEC.

Information Provided by the SEC

You can review and copy information about the Funds (including their prospectuses, the SAI and shareholder reports) at the SEC's Public Reference Room in Washington, DC. To find out more about the operation of the Public Reference Room, call the SEC at 202.551.8090. Reports and other information about the Fund are also available in the EDGAR Database on the SEC's website at http://www.sec.gov, or you can receive copies of this information, for a fee, by electronic request at the following e-mail address: publicinfo@sec.gov. You can also obtain copies of this information by writing the Public Reference Section, Securities and Exchange Commission, Washington, DC 20549-0102.

The investment company registration number of Columbia Acorn Trust, of which each of these Funds are a series, is 811-01829.

One Financial Center, Boston, MA 02111-2621

800.345.6611 www.columbiamanagement.com

SHC-44/19904-0609 09/86289

Q2 2009

Columbia Management^®

Columbia Acorn Family of Funds

Class A, B and C Shares

Managed by Columbia Wanger Asset Management, L.P.

Semiannual Report

June 30, 2009

n Columbia^SM
Acorn® Fund

n Columbia^SM
Acorn International®

n Columbia^SM
Acorn USA®

n Columbia^SM
Acorn International Select^SM

n Columbia^SM
Acorn Select^SM

n Columbia^SM
Thermostat Fund^SM

NOT FDIC INSURED

NOT BANK ISSUED

May Lose Value

No Bank Guarantee

You are invited to the 2009 Columbia Acorn Funds Shareholder Information Meeting!

When: Wednesday, September 30, 2009
12 noon to 1 p.m. Central time

Where: Chase Bank Auditorium, Plaza Level
10 South Dearborn Street
Chicago, Illinois

A buffet lunch will be served at 11:30 a.m.

If you plan to join us in Chicago, please RSVP by September 25
by calling (800) 922-6769.

View a Replay on our Website

For those who are unable to join us in Chicago, a webcast replay of the meeting will be available from October 7 through October 31, 2009, at www.columbiafunds.com.
Look under "New and Noteworthy" on our home page for more information.

Robert E. Nason Remembered

Robert E. Nason

Bob's tenure as Trust chairman occurred during a period of change in the regulatory environment and several changes involving the Funds' advisor. Throughout, he served shareholders well and his letters to shareholders in the Funds' annual reports were thoughtful and informative.

Bob is survived by his wife Carol, son Steven (Abbie Baynes), daughter Jill and grandchildren Sara and Ben.

We are fortunate to have known Bob and we will miss him. He was a man of great vision and we will strive to build on the momentum he created and to maintain the legacies of the Columbia Acorn Trust.

Allan Muchin

Vice Chairman of the Board of Trustees
Columbia Acorn Trust

Charles McQuaid

President and Chief Investment Officer
Columbia Wanger Asset Management, L.P.

Columbia Acorn Family of Funds

Table of Contents

NAVs and 2009 Mid-Year Distributions					2

Descriptions of Indexes					3

Share Class Performance					4

Performance At A Glance					5

Squirrel Chatter II: Agriculture's Amazing Progress					6

Understanding Your Expenses					9

Columbia Acorn Fund

In a Nutshell					11

At a Glance					12

Major Portfolio Changes					23

Statement of Investments					26

Columbia Acorn International

In a Nutshell					13

At a Glance					14

Major Portfolio Changes					38

Statement of Investments					40

Portfolio Diversification					47

Columbia Acorn USA

In a Nutshell					15

At a Glance					16

Major Portfolio Changes					48

Statement of Investments					50

Columbia Acorn International Select

In a Nutshell					17

At a Glance					18

Major Portfolio Changes					58

Statement of Investments					60

Portfolio Diversification					63

Columbia Acorn Select

In a Nutshell					19

At a Glance					20

Major Portfolio Changes					64

Statement of Investments					65

Columbia Thermostat Fund

In a Nutshell					21

At a Glance					22

Statement of Investments					69

Columbia Acorn Family of Funds

Statements of Assets and Liabilities					71

Statements of Operations					72

Statements of Changes in Net Assets					73

Financial Highlights					77

Notes to Financial Statements					83

Federal Income Tax Information

Management Fee Evaluation of the

Senior Officer					91

Board Approval of the Advisory Agreement					96

Board of Trustees and Management

of Columbia Acorn Funds

Columbia Acorn Family of Funds

Net Asset Value Per Share as of 6/30/09

	Columbia Acorn Fund		Columbia Acorn International		Columbia Acorn USA		Columbia Acorn International Select		Columbia Acorn Select		Columbia Thermostat Fund
Class A	$	18.88	$	27.47	$	17.16	$	19.52	$	17.09	$	8.88
Class B	$	17.71	$	26.82	$	16.11	$	18.71	$	16.10	$	8.93
Class C	$	17.57	$	26.74	$	16.01	$	18.62	$	16.00	$	8.92

2009 Mid-year Distributions

	Short-term Capital Gains	Long-term Capital Gains	Ordinary Income		Reinvestment Price
Columbia Acorn International – Class A	None	None	$	0.4093	$	27.57
Columbia Acorn International – Class B	None	None	$	0.2042	$	26.93
Columbia Acorn International – Class C	None	None	$	0.1417	$	26.85
Columbia Acorn International Select – Class A	None	None	$	0.1494	$	19.55
Columbia Thermostat Fund – Class A	None	None	$	0.0016	$	9.08

Columbia Acorn Family of Funds

Descriptions of Indexes Included in this Report

• Standard & Poor's (S&P) 500 Index tracks the performance of 500 widely held, large-capitalization U.S. stocks.

• Standard & Poor's (S&P) MidCap 400 Index is a market value-weighted index that tracks the performance of 400 mid-cap U.S. companies.

• S&P Global Ex-U.S. SmallCap Index is an unmanaged index consisting of the bottom 20% of institutionally investable capital of developed and emerging countries, outside the United States.

Unlike mutual funds, indexes are not managed and do not incur fees or expenses. It is not possible to invest directly in an index.

Columbia Acorn Family of Funds

Share Class Performance Average Annual Total Returns through 6/30/09

	Class A						Class B*						Class C
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Columbia Acorn Fund (10/16/00)
3 months**		20.87	%		13.92	%		20.64	%		15.64	%		20.59	%		19.59	%
Year to date**		9.64	%		3.34	%		9.25	%		4.25	%		9.20	%		8.20	%
1 year		-26.03	%		-30.28	%		-26.52	%		-30.17	%		-26.64	%		-27.37	%
3 years		-7.97	%		-9.77	%		-8.54	%		-9.31	%		-8.71	%		-8.71	%
5 years		0.67	%		-0.52	%		0.01	%		-0.30	%		-0.14	%		-0.14	%
Life of fund		5.47	%		4.76	%		4.79	%		4.79	%		4.70	%		4.70	%
Columbia Acorn International (10/16/00)
3 months**		33.20	%		25.54	%		32.92	%		27.92	%		32.88	%		31.88	%
Year to date**		21.05	%		14.09	%		20.59	%		15.59	%		20.54	%		19.54	%
1 year		-28.32	%		-32.44	%		-28.79	%		-32.33	%		-28.89	%		-29.59	%
3 years		-3.56	%		-5.45	%		-4.17	%		-4.97	%		-4.32	%		-4.32	%
5 years		8.10	%		6.83	%		7.39	%		7.09	%		7.27	%		7.27	%
Life of fund		4.50	%		3.79	%		3.81	%		3.81	%		3.75	%		3.75	%
Columbia Acorn USA (10/16/00)
3 months**		19.42	%		12.55	%		19.16	%		14.16	%		19.12	%		18.12	%
Year to date**		7.92	%		1.72	%		7.54	%		2.54	%		7.52	%		6.52	%
1 year		-28.41	%		-32.53	%		-28.91	%		-32.46	%		-28.97	%		-29.68	%
3 years		-10.61	%		-12.36	%		-11.18	%		-11.98	%		-11.32	%		-11.32	%
5 years		-2.09	%		-3.25	%		-2.73	%		-3.06	%		-2.86	%		-2.86	%
Life of fund		4.70	%		3.99	%		4.03	%		4.03	%		3.96	%		3.96	%
Columbia Acorn International Select (10/16/00)
3 months**		23.32	%		16.23	%		23.09	%		18.09	%		23.15	%		22.15	%
Year to date**		9.33	%		3.05	%		9.03	%		4.03	%		9.02	%		8.02	%
1 year		-34.91	%		-38.66	%		-35.33	%		-38.56	%		-35.41	%		-36.06	%
3 years		-2.58	%		-4.49	%		-3.21	%		-4.12	%		-3.35	%		-3.35	%
5 years		6.77	%		5.51	%		6.10	%		5.78	%		5.94	%		5.94	%
Life of fund		2.35	%		1.66	%		1.67	%		1.67	%		1.61	%		1.61	%
Columbia Acorn Select (10/16/00)
3 months**		28.01	%		20.65	%		27.78	%		22.78	%		27.80	%		26.80	%
Year to date**		24.11	%		16.97	%		23.66	%		18.66	%		23.65	%		22.65	%
1 year		-33.11	%		-36.96	%		-33.55	%		-36.88	%		-33.64	%		-34.30	%
3 years		-8.08	%		-9.88	%		-8.67	%		-9.53	%		-8.81	%		-8.81	%
5 years		-0.02	%		-1.20	%		-0.71	%		-1.06	%		-0.83	%		-0.83	%
Life of fund		4.45	%		3.75	%		3.76	%		3.76	%		3.69	%		3.69	%
Columbia Thermostat Fund (3/3/03)†
3 months**		19.22	%		12.36	%		19.07	%		14.07	%		18.93	%		17.93	%
Year to date**		7.52	%		1.34	%		7.33	%		2.33	%		7.08	%		6.08	%
1 year		-21.82	%		-26.32	%		-22.21	%		-26.03	%		-22.44	%		-23.20	%
3 years		-4.50	%		-6.37	%		-4.99	%		-5.79	%		-5.25	%		-5.25	%
5 years		-0.09	%		-1.26	%		-0.62	%		-0.91	%		-0.84	%		-0.84	%
Life of fund		3.69	%		2.73	%		3.09	%		3.09	%		2.92	%		2.92	%

*The Funds no longer accept investments from new or existing shareholders in Class B shares.

**Not annualized.

The "with sales charge" returns include the maximum initial sales charge of 5.75% for Class A shares, the applicable contingent deferred sales charge (CDSC) for Class B shares (5%, 4%, 3%, 3%, 2%, 1%, 0% for the first through seventh years after purchase, respectively), and the maximum CDSC of 1.00% of Class C shares during the first year after purchase.

Annual operating expense ratios are as stated in each Fund's prospectus that is current as of the date of this report. Differences in expense ratios disclosed elsewhere in this report may result from including fee waivers and expense reimbursements as well as different time periods used in calculating the ratios. Columbia Acorn Fund: Class A: 1.05%; Class B: 1.65%; Class C: 1.83%. Columbia Acorn International: Class A: 1.31%; Class B: 1.90%; Class C: 2.08%. Columbia Acorn USA: Class A: 1.29%; Class B: 1.92%; Class C: 2.08%. Columbia Acorn International Select: Class A: 1.54%; Class B: 2.17%; Class C: 2.34%. Columbia Acorn Select: Class A: 1.24%; Class B: 1.87%; Class C: 2.04%. Columbia Thermostat Fund has a contractual expense waiver or reimbursement that expires April 30, 2010. Expense ratios without and with the contractual waiver, including fees and expenses associated with the Fund's investments in other investment compan ies are: Class A: 1.40%, 1.22%; Class B: 1.92%, 1.72%; Class C: 2.17%, 1.97%, respectively.

All results shown assume reinvestment of distributions and do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption of fund shares.

Columbia Acorn Family of Funds

Fund Performance vs. Benchmarks Class A Shares, without sales charge,
Average Annual Total Returns through 6/30/09

	2nd quarter*			Year to date*			1 year			3 years			5 years			Life of Fund
Columbia Acorn Fund (LACAX) (10/16/00)		20.87	%		9.64	%		-26.03	%		-7.97	%		0.67	%		5.47	%
Russell 2500 Index		20.27	%		6.52	%		-26.72	%		-9.31	%		-0.93	%		2.77	%
S&P 500 Index		15.93	%		3.16	%		-26.21	%		-8.22	%		-2.24	%		-2.72	%
Lipper Small-Cap Core Index		22.23	%		8.23	%		-25.01	%		-8.74	%		-0.93	%		2.89	%
Lipper Mid-Cap Growth Index		19.10	%		13.91	%		-30.39	%		-6.29	%		0.39	%		-3.93	%
Columbia Acorn International (LAIAX) (10/16/00)		33.20	%		21.05	%		-28.32	%		-3.56	%		8.10	%		4.50	%
S&P Global Ex-U.S. Between $500 Million and $5 Billion Index		34.15	%		24.54	%		-26.45	%		-4.02	%		7.13	%		7.88	%
S&P Global Ex-U.S. SmallCap Index		35.88	%		24.20	%		-29.89	%		-6.09	%		5.69	%		6.74	%
MSCI EAFE Index		25.43	%		7.95	%		-31.35	%		-7.98	%		2.31	%		0.95	%
Lipper International Small/Mid Growth Index		33.20	%		23.05	%		-32.90	%		-7.44	%		5.22	%		2.56	%
Columbia Acorn USA (LAUAX) (10/16/00)		19.42	%		7.92	%		-28.41	%		-10.61	%		-2.09	%		4.70	%
Russell 2000 Index		20.69	%		2.64	%		-25.01	%		-9.89	%		-1.71	%		1.99	%
Russell 2500 Index		20.27	%		6.52	%		-26.72	%		-9.31	%		-0.93	%		2.77	%
S&P 500 Index		15.93	%		3.16	%		-26.21	%		-8.22	%		-2.24	%		-2.72	%
Lipper Small-Cap Growth Index		20.60	%		13.14	%		-25.73	%		-9.04	%		-2.32	%		-2.92	%
Columbia Acorn Int'l Select (LAFAX) (10/16/00)		23.32	%		9.33	%		-34.91	%		-2.58	%		6.77	%		2.35	%
S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index		28.70	%		14.93	%		-30.16	%		-7.29	%		4.30	%		5.32	%
MSCI EAFE Index		25.43	%		7.95	%		-31.35	%		-7.98	%		2.31	%		0.95	%
Lipper International Funds Index		25.64	%		10.11	%		-30.14	%		-6.52	%		3.35	%		1.79	%
Columbia Acorn Select (LTFAX) (10/16/00)		28.01	%		24.11	%		-33.11	%		-8.08	%		-0.02	%		4.45	%
S&P MidCap 400 Index		18.75	%		8.47	%		-28.02	%		-7.54	%		0.36	%		2.93	%
S&P 500 Index		15.93	%		3.16	%		-26.21	%		-8.22	%		-2.24	%		-2.72	%
Lipper Mid-Cap Growth Index		19.10	%		13.91	%		-30.39	%		-6.29	%		0.39	%		-3.93	%
Columbia Thermostat Fund (CTFAX) (3/3/03)†		19.22	%		7.52	%		-21.82	%		-4.50	%		-0.09	%		3.69	%
S&P 500 Index		15.93	%		3.16	%		-26.21	%		-8.22	%		-2.24	%		3.44	%
Barclays Capital U.S. Aggregate Bond Index		1.78	%		1.90	%		6.05	%		6.43	%		5.01	%		4.38	%
Barclays Capital U.S. Intermediate Credit Bond Index		7.59	%		7.53	%		4.28	%		5.05	%		4.04	%		3.92	%
Lipper Flexible Portfolio Funds Index		13.00	%		7.59	%		-21.04	%		-3.36	%		1.16	%		5.09	%
50/50 Blended Benchmark††		8.76	%		2.95	%		-10.69	%		-0.73	%		1.63	%		4.20	%

*Not annualized.

Annual operating expense ratios are as stated in each Fund prospectus that is current as of the date of this report. Differences in expense ratios disclosed elsewhere in this report may result from including fee waivers and expense reimbursements as well as different time periods used in calculating the ratios. Columbia Acorn Fund: Class A: 1.05%; Class B: 1.65%; Class C: 1.83%. Columbia Acorn International: Class A: 1.31%; Class B: 1.90%; Class C: 2.08%. Columbia Acorn USA: Class A: 1.29%; Class B: 1.92%; Class C: 2.08%. Columbia Acorn International Select: Class A: 1.54%; Class B: 2.17%; Class C: 2.34%. Columbia Acorn Select: Class A: 1.24%; Class B: 1.87%; Class C: 2.04%. Columbia Thermostat Fund has a contractual expense waiver or reimbursement that expires April 30, 2010. Expense ratios without and with the contractual waiver, including fees and expenses associated with the Fund's investments in other investment companie s are: Class A: 1.40%, 1.22%; Class B: 1.92%, 1.72%; Class C: 2.17%, 1.97%, respectively.

††The 50/50 Blended Benchmark is a custom supplemental benchmark established by the advisor.

All results shown assume reinvestment of distributions and do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption of fund shares.

Unlike mutual funds, indexes are not actively managed and do not incur fees or expenses. It is not possible to invest directly in an index. For index definitions, see Page 3.

Squirrel Chatter II: Agriculture's Amazing Progress

Launching a "Green Revolution" in Developing Countries

Recent Conditions and Future Prospects

Columbia Acorn Funds News

Resumption of Securities Lending

As mentioned in our third quarter report last year, securities lending is the temporary lending of a Fund's portfolio securities to broker/dealers and other institutional investors. The Fund retains the benefits of owning the securities, including receipt of dividends or interest generated by the security. The Fund also receives a fee for the loan. The Fund may recall the loans at any time and may do so in order to vote proxies or to sell the loaned securities. Furthermore, borrowers provide the Fund with cash collateral that exceeds the value of the securities on loan. The Fund could lose money if it incurred a loss on the reinvestment of the cash collateral. Cash collateral for the program is invested in the Dreyfus Government Cash Management Fund. The securities lending agent is Goldman Sachs Agency Lending. Thus far, shareholders have received modest benefits and incurred no losses from the program.

Charles P. McQuaid

President and Chief Investment Officer
Columbia Wanger Asset Management, L.P.

¹ Mazoyer, Marcel and Roudart, Laurence, A History of World Agriculture, (New York, NY, Monthly Review Press, 2006).

² Federico, Giovanni, Feeding The World, (Princeton and Oxford, Princeton University Press, 2005).

³ Ibid, pg. 97.

⁴ Ibid, pgs. 55, 19.

⁵ Mazoyer, Marcel and Roudart, Laurence, op. cit., pg 11.

⁶ Hesser, Leon, The Man Who Fed The World, (Dallas, TX, Durban House, 2006).

⁸ ISAAA Brief 39-2008: Executive Summary, "Global Status of Commercialized Biotech/GM Crops: 2008, The First Thirteen Years, 1996 to 2008," available at www.isaaa.org.

⁹ "GM crops: global, socio-economic and environmental impacts 1996-2007," a research paper written by Graham Brookes and Peter Barfoot of PG Economics Ltd, Dorchester, U.K., May 2009.

Understanding Your Expenses

Analyzing Your Fund's Expenses

To illustrate these ongoing costs, we have provided examples and calculated the expenses paid by investors in the Class A, B and C shares of the Columbia Acorn Funds for the last six months. The information in the following table is based on an initial investment of $1,000, which is invested at the beginning of the reporting period and held for the entire period. Expense information is calculated two ways and each method provides you with different results. The amount listed in the "Actual" column is calculated using each Fund's actual operating expenses and total return for the period. The amount listed in the "Hypothetical" column assumes that the return each year is 5% before expenses and then applies each Fund's actual expense ratio for the period to the hypothetical return. You should not use the hypothetical account values and expenses to estimate either your actual account balance at the end of the period or the expenses you paid during the reporting period. See the "Compare With Other Funds" information for details on using the hypothetical data.

Compare With Other Funds

Estimating Your Actual Expenses

To estimate the expenses that you actually paid over the period, first you will need your account balance at the end of the period:

• For shareholders who receive their account statements from their brokerage firm, contact your brokerage firm to obtain your account balance.

1. Divide your ending account balance by $1,000. For example, if an account balance was $8,600 at the end of the period, the result would be 8.6.

January 1, 2009 – June 30, 2009

	Account value at the beginning of the period ($)				Account value at the end of the period ($)				Expenses paid during the period ($)				Fund's annualized expense ratio (%)*
	Actual		Hypothetical		Actual		Hypothetical		Actual		Hypothetical		Actual
Columbia Acorn Fund
Class A		1,000.00		1,000.00		1,096.40		1,019.24		5.82		5.61		1.12
Class B		1,000.00		1,000.00		1,092.48		1,015.87		9.34		9.00		1.80
Class C		1,000.00		1,000.00		1,091.99		1,015.17		10.06		9.69		1.94
Columbia Acorn International
Class A		1,000.00		1,000.00		1,210.51		1,017.60		7.95		7.25		1.45
Class B		1,000.00		1,000.00		1,205.89		1,014.03		11.87		10.84		2.17
Class C		1,000.00		1,000.00		1,205.40		1,013.54		12.41		11.33		2.27
Columbia Acorn USA
Class A		1,000.00		1,000.00		1,079.19		1,018.05		7.01		6.80		1.36
Class B		1,000.00		1,000.00		1,075.38		1,014.38		10.81		10.49		2.10
Class C		1,000.00		1,000.00		1,075.18		1,013.98		11.22		10.89		2.18
Columbia Acorn International Select
Class A		1,000.00		1,000.00		1,093.28		1,017.01		8.15		7.85		1.57
Class B		1,000.00		1,000.00		1,090.30		1,013.88		11.40		10.99		2.20
Class C		1,000.00		1,000.00		1,090.20		1,012.65		12.70		12.23		2.45
Columbia Acorn Select
Class A		1,000.00		1,000.00		1,241.10		1,017.90		7.72		6.95		1.39
Class B		1,000.00		1,000.00		1,236.59		1,014.38		11.65		10.49		2.10
Class C		1,000.00		1,000.00		1,236.49		1,013.74		12.37		11.13		2.23
Columbia Thermostat Fund
Class A		1,000.00		1,000.00		1,075.18		1,022.32		2.57		2.51		0.50
Class B		1,000.00		1,000.00		1,073.29		1,019.84		5.14		5.01		1.00
Class C		1,000.00		1,000.00		1,070.81		1,018.60		6.42		6.26		1.25

Columbia Thermostat Fund's expenses do not include fees and expenses incurred by the Fund from the underlying portfolio funds in which it invests.

*For the six months ended June 30, 2009.

Columbia Acorn Fund

In a Nutshell



Charles P. McQuaid				Robert A. Mohn

Lead Portfolio Manager				Co-Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

Coach	1.4	%
ITT Educational Services	1.2	%
Southwestern Energy	1.2	%
People's United	1.1	%
Bally Technologies	1.0	%
Fugro	1.0	%
FMC Technologies	1.0	%
AmeriCredit	0.8	%
Myriad Genetics	0.6	%
OLAM International	0.4	%
Hexagon	0.4	%
Pacific Rubiales Energy	0.4	%

The stock market did well in the second quarter, jumping up from what appeared to be oversold levels. Columbia Acorn Fund returned 20.87% (Class A shares, without sales charge). The Fund returned somewhat more than its primary benchmark, the Russell 2500 Index, which rose 20.27%. During the first half of 2009, the Fund grew 9.64%, nicely outperforming the 6.52% gain of the Russell 2500 Index. As shown on Page 5, Columbia Acorn Fund also beat most other benchmarks in both periods.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn Fund (LACAX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through June 30, 2009

*Inception 10/16/00*		Year to date*	1 year	5 years	Life of fund
Returns before taxes	NAV POP	9.64% 3.34	-26.03% -30.28	0.67% -0.52	5.47% 4.76
Returns after taxes on distributions	NAV POP	9.64 3.34	-26.10 -30.35	-0.16 -1.34	4.64 3.94
Returns after taxes on distributions and sale of fund shares	NAV POP	6.27 2.17	-16.84 -19.61	0.78 -0.23	4.74 4.11
Russell 2500 Index** (pretax)		6.52	-26.72	-0.93	2.77

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.

Public offering price (POP) returns include the maximum sales charge of 5.75% for Class A shares. Net asset value (NAV) returns do not include sales charges or contingent deferred sales charges (CDSC).

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.05%.

*Year to date data is not annualized.

Columbia Acorn Fund Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn Fund Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	Coach Designer & Retailer of Branded Leather Accessories	1.4%
2.	Crown Castle International Communications Towers	1.4%
3.	Ametek Aerospace/Industrial Instruments	1.3%
4.	Donaldson Industrial Air Filtration	1.2%
5.	ITT Educational Services Post-secondary Degree Services	1.2%
6.	Expeditors International of Washington International Freight Forwarder	1.2%
7.	Southwestern Energy Oil & Gas Producer	1.2%
8.	People's United Connecticut Savings & Loan	1.1%
9.	Alexion Pharmaceuticals Biotech Focused on Orphan Diseases	1.1%
10.	Bally Technologies Slot Machines & Software	1.0%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn Fund (Class A)

October 16, 2000 through June 30, 2009

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. The Russell 2500 Index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings may differ significantly from those in the index. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $11.7 billion

Columbia Acorn International

In a Nutshell



P. Zachary Egan				Louis J. Mendes III

Co-Portfolio Manager				Co-Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

Serco	1.1	%
Capita Group	1.1	%
Educomp Solutions	0.9	%
Central European Distribution	0.8	%
Jain Irrigation Systems	0.7	%
RexLot Holdings	0.6	%

Columbia Acorn International rose 33.20% (Class A shares, without sales charge) in the second quarter, slightly trailing the 34.15% rise of its primary benchmark, the S&P Global Ex-U.S. Between $500 Million and $5 Billion Index. Year to date, the Fund was up 21.05%, 3.49% behind its primary benchmark. Small-cap international stocks led larger-cap international stocks, as exemplified by the MSCI EAFE Index, which was up 25.43% in the quarter and 7.95% year to date.

While coming on the heels of a severe sell-off in 2008, an absolute return north of 30% in a single quarter is always pleasing. This remarkable reversal in market sentiment in the second quarter appears to reflect decreasing anxiety about our economic future, as credit markets show signs of life, in a context of attractive valuations. While the stock market has historically done a good job of anticipating changes in economic fundamentals by several quarters, it is worth noting that the majority of the companies we follow have reported few sightings of "green shoots" presaging a return to global growth. Indeed, the International Monetary Fund expects global economic activity to contract by 1.4% in 2009 before expanding 2.5% in 2010. The major exception to this has been the emerging markets of non-Japan Asia and Latin America. In these economies, the sentiment is now distinctly upbeat. The rapid implementation of a sizeable govern ment stimulus package in China, and an election outcome in India perceived to endorse further economic liberalization, drove this enthusiasm.

On earnings adjusted for cyclicality and on other valuations measures, we believe that international small-cap stocks now trade at a modest discount to their 10-year average.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn International (LAIAX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through June 30, 2009

*Inception 10/16/00*		Year to date*	1 year	5 years	Life of fund
Returns before taxes	NAV POP	21.05% 14.09	-28.32% -32.44	8.10% 6.83	4.50% 3.79
Returns after taxes on distributions	NAV POP	20.43 13.51	-28.68 -32.78	7.32 6.05	3.71 3.00
Returns after taxes on distributions and sale of fund shares	NAV POP	13.68 9.16	-18.40 -21.08	7.27 6.15	3.88 3.26
S&P Global Ex-U.S. Between $500 Million and $5 Billion Index** (pretax)		24.54	-26.45	7.13	7.88

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.31%.

*Year to date data is not annualized.

Columbia Acorn International Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn International Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	Naspers (South Africa) Media in Africa & Other Emerging Markets	1.6%
2.	OLAM International (Singapore) Agriculture Supply Chain Manager	1.5%
3.	Kansai Paint (Japan) Paint Producer in Japan, India, China & Southeast Asia	1.4%
4.	Hong Kong Exchanges and Clearing (Hong Kong) Hong Kong Equity & Derivatives Market Operator	1.3%
5.	Serco (United Kingdom) Facilities Management	1.1%
6.	Intertek Group (United Kingdom) Testing, Inspection & Certification Services	1.1%
7.	Capita Group (United Kingdom) White Collar, Back Office Outsourcing	1.1%
8.	Imtech (Netherlands) Engineering & Technical Services	1.1%
9.	Hexagon (Sweden) Measurement Equipment	1.1%
10.	Singapore Exchange (Singapore) Singapore Equity & Derivatives Market Operator	1.0%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn International (Class A)

October 16, 2000 through June 30, 2009

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. The S&P Global Ex-U.S. Between $500 Million and $5 Billion Index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings may differ significantly from those in the index. It is not possible to invest directly in an index. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $3.3 billion

Columbia Acorn USA

In a Nutshell

Robert A. Mohn

Lead Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

FMC Technologies	2.1	%
ITT Educational Services	1.9	%
Atwood Oceanics	1.6	%
Micros Systems	1.6	%
Bally Technologies	1.6	%
AmeriCredit	1.4	%
Mettler Toleldo	1.3	%
Valley National Bancorp	1.0	%
FLIR Systems	1.0	%
Lakeland Financial	0.7	%
Cephalon	0.6	%
Myriad Genetics	0.6	%
Berkshire Hills Bancorp	0.5	%
MB Financial	0.4	%
Associated Banc-Corp	0.2	%
Immucor	0.2	%

Columbia Acorn USA ended the second quarter up 19.42% (Class A shares, without sales charge). This compares to a 20.69% gain by the Fund's primary benchmark, the Russell 2000 Index. Year to date, the Fund's 7.92% return was well ahead of the benchmark, which gained 2.64%. Small-cap stocks significantly outperformed large caps in the second quarter. The large-cap focused S&P 500 Index gained 15.93% in the quarter, 4.76% behind the Russell 2000 Index.

Stocks of small- and mid-cap companies pose special risks, including possible illiquidity and greater price volatility than stocks of larger, more established companies.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn USA (LAUAX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through June 30, 2009

*Inception 10/16/00*		Year to date*	1 year	5 years	Life of fund
Returns before taxes	NAV POP	7.92% 1.72	-28.41% -32.53	-2.09% -3.25	4.70% 3.99
Returns after taxes on distributions	NAV POP	7.92 1.72	-28.41 -32.53	-2.60 -3.75	4.37 3.66
Returns after taxes on distributions and sale of fund shares	NAV POP	5.15 1.12	-18.47 -21.14	-1.58 -2.55	4.21 3.58
Russell 2000 Index** (pretax)		2.64	-25.01	-1.71	1.99

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.29%.

*Year to date data is not annualized.

Columbia Acorn USA Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn USA Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	Crown Castle International Communications Towers	2.8%
2.	ESCO Technologies Automatic Electric Meter Readers	2.6%
3.	FMC Technologies Oil & Gas Wellhead Manufacturer	2.1%
4.	Ametek Aerospace/Industrial Instruments	2.0%
5.	tw telecom Fiber Optic Telephone/Data Services	1.9%
6.	ITT Educational Services Post-secondary Degree Services	1.9%
7.	Informatica Enterprise Data Integration Software	1.7%
8.	Global Payments Credit Card Processor	1.7%
9.	Atwood Oceanics Offshore Drilling Contractor	1.6%
10.	Micros Systems Information Systems for Restaurants & Hotels	1.6%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn USA (Class A)

October 16, 2000 through June 30, 2009

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. The Russell 2000 Index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings may differ significantly from those in the index. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $1.1 billion

Columbia Acorn International Select

In a Nutshell

Christopher J. Olson

Lead Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

Naspers	4.9	%
Serco	4.7	%
Pacific Rubiales Energy	3.3	%
Intertek Group	3.3	%
Nintendo	2.6	%
Jupiter Telecommunications	2.0	%
Hexagon	1.8	%
Cephalon	1.4	%

Columbia Acorn International Select ended the second quarter up 23.32% (Class A shares, without sales charge), underperforming its primary benchmark, the S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index, which gained 28.70%. Year to date, the Fund was up 9.33%, while its benchmark posted a 14.93% return. The Fund's less cyclical portfolio, which helped performance during the recent market crash, held the Fund back as investors rushed into riskier assets.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn International Select (LAFAX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through June 30, 2009

*Inception 10/16/00*		Year to date*	1 year	5 years	Life of fund
Returns before taxes	NAV POP	9.33% 3.05	-34.91% -38.66	6.77% 5.51	2.35% 1.66
Returns after taxes on distributions	NAV POP	9.04 2.77	-35.09 -38.82	6.51 5.26	2.20 1.51
Returns after taxes on distributions and sale of fund shares	NAV POP	6.07 1.98	-22.69 -25.13	6.02 4.91	2.12 1.51
S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index** (pretax)		14.93	-30.16	4.30	5.32

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.54%.

*Year to date data is not annualized.

Columbia Acorn International Select Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn International Select Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	Naspers (South Africa) Media in Africa & Other Emerging Markets	4.9%
2.	Serco (United Kingdom) Facilities Management	4.7%
3.	Capita Group (United Kingdom) White Collar, Back Office Outsourcing	3.7%
4.	Israel Chemicals (Israel) Producer of Potash, Phosphates, Bromine, & Specialty Chemicals	3.5%
5.	Pacific Rubiales Energy (Canada) Oil Production & Exploration in Colombia	3.3%
6.	Intertek Group (United Kingdom) Testing, Inspection & Certification Services	3.3%
7.	Potash Corp. of Saskatchewan (Canada) World's Largest Producer of Potash	3.2%
8.	NHN (South Korea) South Korea's Largest Online Search Engine	2.9%
9.	Kansai Paint (Japan) Paint Producer in Japan, India, China & Southeast Asia	2.7%
10.	Alexion Pharmaceuticals (United States) Biotech Focused on Orphan Diseases	2.7%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn International Select (Class A)

October 16, 2000 through June 30, 2009

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. The S&P Developed Ex-U.S. Between $2 Billion and $10 Billion Index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings may differ significantly from those in the index. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $336.9 million

Columbia Acorn Select

In a Nutshell

Ben Andrews

Lead Portfolio Manager

Fund's Positions
in Mentioned Holdings

As a percentage of net assets,
as of 6/30/09

ITT Educational Services	5.5	%
Pacific Rubiales Energy	5.3	%
Safeway	4.6	%
Hertz	4.1	%
Tetra Technologies	3.6	%
Expedia	3.0	%
Waste Management	2.8	%
MF Global	2.4	%
Conseco	2.4	%
Discover Financial Services	0.9	%
SBA Communications	0.8	%
Steelcase	0.8	%
Gran Tierra Energy	0.5	%
Princeton Review	0.3	%

Columbia Acorn Select gained 28.01% (Class A shares, without sales charge) in the second quarter, which was 9.26% more than the Fund's primary benchmark, the S&P MidCap 400 Index. Mid-cap stocks outperformed large caps. The S&P 500 Index was up 15.93%.

Columbia Acorn Select's year-to-date performance was a positive 24.11% vs. gains of 8.47% for the S&P MidCap 400 Index and 3.16% for the S&P 500 Index. Looking at the drivers of this solid outperformance, we see large gains in Pacific Rubiales Energy, MF Global, Expedia and Tetra Technologies. On the downside, Conseco, Safeway, Cephalon and Waste Management were the Fund's biggest detractors to year-to-date performance.

I also worry about a possible return of energy price inflation in the next couple of years. I believe the market should grind higher in the coming months, but our economy is still weak and more excessive volatility probably lies ahead. We will continue to review and fine-tune our approach to try and get the most out of the markets as we struggle through the rough patches.

Portfolio holdings are subject to change periodically and may not be representative of current holdings.

Columbia Acorn Select (LTFAX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through June 30, 2009

*Inception 10/16/00*		Year to date*	1 year	5 years	Life of fund
Returns before taxes	NAV POP	24.11% 16.97	-33.11% -36.96	-0.02% -1.20	4.45% 3.75
Returns after taxes on distributions	NAV POP	24.11 16.97	-33.11 -36.96	-0.38 -1.56	4.19 3.48
Returns after taxes on distributions and sale of fund shares	NAV POP	15.67 11.03	-21.52 -24.02	0.09 -0.91	3.92 3.29
S&P MidCap 400 Index** (pretax)		8.47	-28.02	0.36	2.93

All results shown assume reinvestment of distributions.

**The Fund's primary benchmark.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.

The Fund's Class A shares annual operating expense ratio, as stated in the current prospectus, is 1.24%.

*Year to date data is not annualized.

Columbia Acorn Select Portfolio Diversification

as a percentage of net assets, as of 6/30/09

Columbia Acorn Select Top 10 Holdings

as a percentage of net assets, as of 6/30/09

1.	ITT Educational Services Post-secondary Degree Services	5.5%
2.	Pacific Rubiales Energy (Canada) Oil Production & Exploration in Colombia	5.3%
3.	SkillSoft Web-based Learning Solutions (E-Learning)	4.8%
4.	Safeway Supermarkets	4.6%
5.	Hertz Largest U.S. Rental Car Operator	4.1%
6.	Quanta Services Electrical & Telecom Construction Services	3.9%
7.	Tetra Technologies U.S.-based Service Company with Life of Field Approach	3.6%
8.	Expedia Online Travel Services Company	3.0%
9.	Coach Designer & Retailer of Branded Leather Accessories	2.9%
10.	Career Education Post-secondary Education	2.8%

The Fund's top 10 holdings and portfolio diversification vary with changes in portfolio investments. See the Statement of Investments for a complete list of the Fund's holdings.

The Growth of a $10,000 Investment in Columbia Acorn Select (Class A)

October 16, 2000 through June 30, 2009

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. The S&P MidCap 400 Index is unmanaged and returns for both the index and the Fund include reinvested dividends and capital gains. Although the index is provided for use in assessing the Fund's performance, the Fund's holdings differ significantly from those in the index. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $1.5 billion

Columbia Thermostat Fund

In a Nutshell

Charles P. McQuaid

Lead Portfolio Manager

Columbia Thermostat Fund ended the second quarter up 19.22% (Class A shares, without sales charge), outperforming the 15.93% gain in the S&P 500 Index, the Fund's primary stock benchmark, and the 1.78% return of the Barclays Capital U.S. Aggregate Bond Index, the Fund's primary bond benchmark. Year to date the Fund was up 7.52%, well ahead of the 3.16% gain of the S&P 500 Index and the 1.90% return for the Barclays Capital U.S. Aggregate Bond Index.

Results of the Funds Owned in Columbia Thermostat Fund as of June 30, 2009

Stock Funds Fund	Weightings in category			2nd quarter			Year to date returns to 6/30/09
Columbia Acorn Fund		15	%		20.90	%		9.77	%
Columbia Acorn Select		10	%		28.11	%		24.38	%
Columbia Marsico Growth Fund		15	%		15.22	%		4.70	%
Columbia Acorn International		15	%		33.30	%		21.31	%
Columbia Dividend Income Fund		20	%		12.31	%		-0.86	%
Columbia Large Cap Enhanced Core Fund		25	%		15.74	%		1.86	%
*Weighted Average* *Equity Return/Loss*		*100*	%		*19.54*	%		*7.90*	%

Columbia Thermostat Fund did not hold bond funds in the second quarter or year-to-date periods.

Columbia Thermostat Fund (CTFAX)

At a Glance

Pretax and After-tax Average Annual Total Returns (Based on Class A Share Returns)

through June 30, 2009

*Inception 3/3/03*		Year to date*	1 year	5 years	Life of fund
Returns before taxes	NAV POP	7.52% 1.34	-21.82% -26.32	-0.09% -1.26	3.69% 2.73
Returns after taxes on distributions	NAV POP	7.52 1.34	-22.33 -26.79	-1.76 -2.91	2.27 1.31
Returns after taxes on distributions and sale of fund shares	NAV POP	4.89 0.87	-14.04 -16.97	-0.58 -1.57	2.73 1.89
S&P 500 Index** (pretax)		3.16	-26.21	-2.24	3.44
Barclays Capital U.S. Aggregate Bond Index** (pretax)		1.90	6.05	5.01	4.38
Barclays Capital U.S. Intermediate Credit Bond Index (pretax)		7.53	4.28	4.04	3.92
Lipper Flexible Portfolio Funds Index (pretax)		7.59	-21.04	1.16	5.09

All results shown assume reinvestment of distributions.

**The Fund's primary stock and bond benchmarks, respectively.

After-tax returns are calculated using the highest historical individual federal marginal income tax rates, and do not reflect the impact of state and local taxes. Returns after taxes on distributions and sale of Fund shares reflect the tax impact of gains or losses realized when Fund shares are sold. The returns are taxed at the maximum rate and assume shares were purchased at the beginning of the period. Actual after-tax returns depend on the investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Indexes do not reflect any deduction for fees, expenses or taxes. Investment returns and principal value may fluctuate, resulting in a gain or loss on sale.

The Fund's annual operating expense ratio, as stated in the current prospectus, reflects a contractual expense waiver or reimbursement that expires April 30, 2010. Class A expense ratios without and with the contractual waiver, including fees and expenses associated with the Fund's investment in other investment companies, are 1.40% and 1.22%, respectively. Absent the waiver or reimbursement, performance results would have been lower.

*Year to date data is not annualized.

Columbia Thermostat Fund Portfolio Weightings

as a percentage of assets in each investment category, as of 6/30/09

The Growth of a $10,000 Investment in Columbia Thermostat Fund (Class A)

March 3, 2003 through June 30, 2009

Illustration is based on a hypothetical $10,000 investment from inception in Class A shares of the Fund, which includes a 5.75% maximum initial sales charge. Although the indexes are provided for assessing the Fund's performance, the Fund's holdings differ significantly from those in the indexes. The Barclays Capital U.S. Aggregate Bond Index became the Fund's primary benchmark for debt securities effective July 1, 2008. The Fund changed to this debt benchmark because the advisor believes it is a more appropriate comparison to the Fund's investments. The indexes are unmanaged and returns for both the indexes and the Fund include reinvested dividends and capital gains. It is not possible to invest directly in an index. The graph does not reflect taxes that a shareholder would pay on Fund distributions or on a sale of Fund shares.

Total Net Assets of the Fund: $125.3 million

Columbia Acorn Fund

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Information
AboveNet		0		100,000
Actuate		2,500,000		2,785,803
Art Technology Group		0		885,000
Blue Coat Systems		0		400,576
CommScope		0		1,085,000
Entegris		3,000,000		3,750,000
Eutelsat (France)		0		250,000
F5 Networks		0		665,000
Informatica		5,500,000		6,700,000
IXYS		2,035,000		2,135,000
ManTech International		180,000		225,000
Mettler Toledo		1,300,000		1,385,000
Monolithic Power Systems		315,000		645,000
Netgear		870,000		970,000
Novell		12,300,000		12,500,000
ON Semiconductor		2,914,000		3,384,000
SBA Communications		0		1,000,000
Singapore Exchange (Singapore)		3,400,000		10,000,000
VisionChina Media - ADR (China)		2,000,000		2,700,000
WNS - ADR (India)		39,325		709,260
Industrial Goods & Services
Aalberts Industries (Netherlands)		2,777,000		2,869,585
Albemarle		1,350,000		1,530,000
Carbone Lorraine (France)		189,580		515,380
Celanese		0		450,000
Drew Industries		1,324,000		1,600,000
FreightCar America		0		225,000
GrafTech International		0		1,700,000
HEICO		850,000		1,225,000
Imtech (Netherlands)		1,041,000		1,093,050
Interline Brands		2,000,000		2,600,000
M/I Homes		484,000		584,000
MOOG		1,520,000		1,660,000
Neopost (France)		0		114,000
Novozymes (Denmark)		255,000		363,000
NVR		0		60,000
OLAM International (Singapore)		15,200,000		30,000,000
Pall		1,375,000		1,675,000
Ritchie Brothers Auctioneers		200,000		437,500
Serco (United Kingdom)		607,259		3,000,000
Sociedad Quimica y Minera de Chile - ADR (Chile)		1,800,000		2,000,000
Consumer Goods & Services
American Apparel		0		830,444
Avis Budget Group		0		6,000,000
Bebe Stores		0		445,700
Charlotte Russe		0		1,706,102

	Number of Shares
	03/31/09		06/30/09
Charming Shoppes		0		2,751,621
Chico's FAS		2,850,000		7,507,000
Children's Place Retail Stores		200,000		1,061,000
Herman Miller		3,000,000		3,500,000
Hertz		0		3,000,000
Hibbett Sports		264,835		600,000
HNI		975,000		1,245,000
Hot Topic		1,987,000		3,308,890
Interface		0		646,780
J Crew Group		800,000		1,964,000
Knoll		3,300,000		4,000,000
Lifestyle International (Hong Kong)		0		3,381,400
Lululemon Athletica		0		1,800,000
New Oriental Education & Technology - ADR (China)		0		386,000
Princeton Review		2,800,000		2,974,300
Saks		0		3,100,000
Steelcase		0		2,016,856
True Religion Apparel		1,150,000		1,783,000
Urban Outfitters		3,950,000		4,020,000
Winnebago		570,000		850,000
Finance
Berkshire Hills Bancorp		100,000		234,693
CIT Group		0		7,000,000
Cullen/Frost Bankers		0		250,000
GATX		1,330,000		1,730,000
Investment Technology Group		647,502		700,000
McGrath Rentcorp		2,090,000		2,266,361
Sandy Spring Bancorp		0		178,550
TCF Financial		3,550,000		4,150,000
ViewPoint Financial		15,090		500,000
Wilmington Trust		0		1,690,000
Health Care
Alexion Pharmaceuticals		2,850,000		3,000,000
American Medical Systems		2,020,200		2,400,000
Beckman Coulter		0		300,000
Cepheid		3,100,000		4,000,000
Luminex		1,142,100		2,453,000
Medarex		4,300,000		4,800,000
NPS Pharmaceuticals		0		669,465

See accompanying notes to financial statements.

	Number of Shares
	03/31/09		06/30/09
Purchases (continued)
Energy & Minerals
Carrizo Oil & Gas		1,200,000		1,400,000
Fugro (Netherlands)		2,665,488		2,809,568
Gran Tierra Energy (Canada)		0		4,000,000
Royal Gold		0		300,000
ShawCor (Canada)		1,070,000		1,670,000
Silver Wheaton (Canada)		1,000,000		2,700,000
Tetra Technologies		1,038,000		1,198,000
Trinidad Drilling (Canada)		0		4,870,800
Other Industries
Ascendas Real Estate Investment Trust (Singapore)		0		13,069,100
Corporate Office Properties		715,000		900,000
DCT Industrial Trust		0		3,750,000
JB Hunt Transport Services		2,000,000		2,110,000
Kite Realty Group		1,900,000		2,300,000
Macerich Company		635,000		1,065,000
Red Electrica de Espana (Spain)		0		536,000
Washington Real Estate Investment Trust		0		700,000
World Fuel Services		0		200,000

	Number of Shares
	03/31/09		06/30/09
Sales
Information
Activision Blizzard		300,000		0
American Tower		2,250,000		1,750,000
Avnet		3,465,000		3,125,000
Concur Technologies		2,000,000		1,800,000
Discovery Communications		2,250,000		1,820,000
FLIR Systems		5,000,000		3,276,660
Hexagon (Sweden)		6,100,000		5,200,000
Mediacom Communications		4,000,000		3,655,915
Red Hat		3,000,000		2,000,000
Rofin-Sinar Technologies		470,000		320,000
Rogers		280,000		0
SES (France)		1,250,000		893,000
Tellabs		2,800,000		0
Teradata		1,615,000		340,000
Trimble Navigation		2,840,000		2,490,000
Varian		540,897		500,000
Viad		124,674		0
Industrial Goods & Services
Administaff		2,025,000		1,935,000
American Commercial Lines		400,000		0
Aptargroup		500,000		350,000
Expeditors International of Washington		5,300,000		4,200,000
Martin Marietta Materials		850,000		700,000
Oshkosh		3,500,000		3,150,000
Pentair		2,600,000		2,300,000
TrueBlue		1,200,000		800,000
Union Tool (Japan)		130,700		0
Waste Connections		1,850,000		1,200,000
WW Grainger		1,200,000		1,000,000
Consumer Goods & Services
Abercrombie & Fitch		2,625,000		2,505,000
Coach		6,730,000		5,930,000
Expedia		5,000,000		4,700,000
GameStop		1,450,000		647,000
Intralot (Greece)		2,380,000		0
ITT Educational Services		1,442,303		1,400,000
Macy's		1,950,000		0
Nordstrom		1,200,000		0
Vail Resorts		2,265,690		1,950,000
Finance
Affiliated Managers Group		230,000		0
Cohen & Steers		1,150,000		550,000
People's United		12,063,899		8,563,899

See accompanying notes to financial statements.

Columbia Acorn Fund

Major Portfolio Changes in the Second Quarter (Unaudited), continued

	Number of Shares
	03/31/09		06/30/09
Sales (continued)
Health Care
Array Biopharma		1,509,185		0
Cephalon		1,115,000		1,000,000
Edwards Lifesciences		1,000,000		750,000
Hologic		2,800,000		1,900,000
ICU Medical		1,250,000		850,000
Kinetic Concepts		1,300,000		900,000
Lincare Holdings		1,150,000		0
Meridian Biosciences		790,000		0
Nektar Therapeutics		5,325,000		4,631,195
Rhoen-Klinikum (Germany)		1,650,000		975,300
Savient Pharmaceuticals		3,000,000		2,000,000
Seattle Genetics		4,400,000		3,834,516
Energy & Minerals
Exterran Holdings		1,055,000		502,000
Ultra Petroleum		1,300,000		975,000
Other Industries
General Growth Properties		2,200,000		0
Jiangsu Expressway (China)		34,804,000		0

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 97.3%
Information 24.7%
		> Business Software 4.8%
	6,700,000	Informatica (a)(b)	$	115,173
		Enterprise Data Integration Software
	1,150,000	Quality Systems (c)		65,504
		IT Systems for Medical Groups & Ambulatory Care Centers
	2,480,544	Micros Systems (a)		62,808
		Information Systems for Restaurants & Hotels
	12,500,000	Novell (a)		56,625
		Directory, Operating System & Identity Management Software
	1,800,000	Concur Technologies (a)		55,944
		Web Enabled Cost & Expense Management Software
	1,525,000	ANSYS (a)		47,519
		Simulation Software for Engineers & Designers
	2,000,000	Red Hat (a)		40,260
		Maintenance & Support for Open Source & Middleware
	2,425,000	Kenexa (a)(b)		28,057
		Recruiting & Workforce Management Solutions
	1,800,000	Blackbaud		27,990
		Software & Services for Non-profits
	3,050,000	Radiant Systems (a)(b)		25,315
		IT Systems for Restaurants, Convenience Stores & Retail Stores
	2,785,803	Actuate (a)(b)		13,316
		Information Delivery Software & Solutions
	1,000,000	NetSuite (a)(c)		11,810
		End to End IT Systems Solution Delivered Over the Web
	700,000	Avid Technology (a)		9,387
		Digital Nonlinear Editing Software & Systems
	885,000	Art Technology Group (a)		3,363
		Software & Tools to Optimize Websites for E-Commerce
				563,071
		> Instrumentation 3.3%
	1,385,000	Mettler Toledo (a)		106,853
		Laboratory Equipment
	3,276,660	FLIR Systems (a)		73,921
		Infrared Cameras
	2,490,000	Trimble Navigation (a)		48,879
		GPS-based Instruments
	5,200,000	Hexagon (Sweden)		47,045
		Measurement Equipment
	500,000	Dionex (a)		30,515
		Ion & Liquid Chromatography
	2,750,000	IPG Photonics (a)(b)		30,167
		Fiber Lasers
	500,000	Varian (a)		19,715
		Analytical Instruments
	1,053,965	FARO Technologies (a)(b)		16,368
		Precision Measurement Equipment
	400,000	Hamamatsu Photonics (Japan)		7,625
		Optical Sensors for Medical & Industrial Applications

Number of Shares			Value (000)
	320,000	Rofin-Sinar Technologies (a)	$	6,403
		Laser Systems
				387,491
		> Computer Hardware & Related Equipment 2.8%
	3,800,000	Amphenol		120,232
		Electronic Connectors
	2,400,000	II-VI (a)(b)		53,208
		Laser Optics & Specialty Materials
	1,340,000	Dolby Laboratories (a)		49,955
		Audio Technology for Consumer Electronics
	1,400,000	Zebra Technologies (a)		33,124
		Bar Code Printers
	800,000	Nice Systems - ADR (Israel) (a)		18,456
		Audio & Video Recording Solutions
	970,000	Netgear (a)		13,978
		Networking Products for Small Business & Home
	740,000	Belden CDT		12,358
		Specialty Cable
	944,100	Stratasys (a)		10,376
		Rapid Prototyping Systems
	340,000	Teradata (a)		7,966
		Enterprise Data Warehouse Systems
	500,000	Intermec (a)		6,450
		Bar Code & Wireless LAN Systems
				326,103
		> Mobile Communications 2.2%
	6,575,000	Crown Castle International (a)		157,931
		Communications Towers
	1,750,000	American Tower (a)		55,178
		Communications Towers in USA & Latin America
	1,000,000	SBA Communications (a)		24,540
		Communications Towers
	1,200,000	MetroPCS Communications (a)		15,972
		Discount Cellular Telephone Services
	1,500,000	Globalstar (a)		1,575
		Satellite Mobile Voice & Data Carrier
				255,196
		> Financial Processors 1.6%
	2,919,000	Global Payments		109,346
		Credit Card Processor
	10,000,000	Singapore Exchange (Singapore)		48,855
		Singapore Equity & Derivatives Market Operator
	2,125,000	Hong Kong Exchanges and Clearing (Hong Kong)		32,995
		Hong Kong Equity & Derivatives Market Operator
				191,196
		> Telephone and Data Services 1.5%
	9,500,000	tw telecom (a)(b)		97,565
		Fiber Optic Telephone/Data Services
	4,300,000	Cogent Communications (a)(b)		35,045
		Internet Data Pipelines

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Telephone and Data Services—continued
	8,165,000	PAETEC Holding (a)(b)	$	22,045
		Telephone/Data Services for Business
	2,000,000	General Communications (a)		13,860
		CATV, Web, Phone & Commercial Communications Provider in Alaska
	100,000	AboveNet (a)		8,098
		Metropolitan Fiber Communications Services
				176,613
		> CATV 1.5%
	2,250,000	Discovery Communications, Series C (a)		46,192
	1,820,000	Discovery Communications (a)		41,041
		CATV Programming
	57,000	Jupiter Telecommunications (Japan)		43,215
		Largest Cable Service Provider in Japan
	1,250,000	Liberty Global, Series C (a)		19,763
		CATV Franchises Outside the USA
	3,655,915	Mediacom Communications (a)(b)		18,682
		CATV Franchises
				168,893
		> Semiconductors & Related Equipment 1.4%
	1,035,000	Supertex (a)(b)		25,989
		Analog/Mixed-signal Semiconductors
	1,830,000	Microsemi (a)		25,254
		Analog/Mixed-signal Semiconductors
	3,384,000	ON Semiconductor (a)		23,214
		Mixed-signal & Power Management Semiconductors
	2,135,000	IXYS (b)		21,606
		Power Semiconductors
	1,765,000	Pericom Semiconductor (a)(b)		14,861
		Interface Integrated Circuits (ICs) & Frequency Control Products
	645,000	Monolithic Power Systems (a)		14,455
		High Performance Analog & Mixed Signal Integrated Circuits (ICs)
	2,110,000	Integrated Device Technology (a)		12,744
		Communications Semiconductors
	3,750,000	Entegris (a)		10,200
		Semiconductor Materials Management Products
	500,000	Littelfuse (a)		9,980
		Little Fuses
				158,303
		> Gaming Equipment & Services 1.2%
	4,025,000	Bally Technologies (a)(b)		120,428
		Slot Machines & Software
	1,000,000	Scientific Games (a)		15,770
		Lottery Services Provider
				136,198
		> Internet Related 0.9%
	2,500,000	Switch & Data Facilities (a)(b)		29,325
		Network Neutral Data Centers
	188,000	NHN (South Korea) (a)		25,977
		South Korea's Largest Online Search Engine

Number of Shares			Value (000)
	350,000	Equinix (a)	$	25,459
		Network Neutral Data Centers
	800,000	Akamai (a)		15,344
		Content Delivery Network (CDN) for Better Delivery of Online Content
	590,000	Vasco Data Security International (a)		4,313
		Online Banking Security & Enterprise Network Security
	1,000,000	TheStreet.com		2,090
		Financial Information Websites
				102,508
		> Computer Services 0.8%
	5,000,000	iGate (b)		33,100
		IT & Business Process Outsourcing Services
	1,520,000	SRA International (a)		26,691
		Government IT Services
	1,450,000	Virtusa (a)(b)		11,644
		Offshore IT Outsourcing
	4,500,000	Hackett Group (a)(b)		10,485
		IT Integration & Best Practice Research
	225,000	ManTech International (a)		9,684
		Government IT Services
	709,260	WNS - ADR (India) (a)		6,298
		Offshore BPO (Business Process Outsourcing) Services
				97,902
		> Telecommunications Equipment 0.7%
	1,085,000	CommScope (a)		28,492
		Wireless Infrastructure Equipment & Telecom Cable
	1,380,000	Polycom (a)		27,973
		Video Conferencing Equipment
	665,000	F5 Networks (a)		23,002
		Internet Traffic Management Equipment
	400,576	Blue Coat Systems (a)		6,626
		WAN Acceleration & Network Security
				86,093
		> Business Information & Marketing Services 0.6%
	2,500,000	Navigant Consulting (a)(b)		32,300
		Financial Consulting Firm
	540,000	FTI Consulting (a)		27,389
		Financial Consulting Firm
	1,240,000	InfoGROUP (a)		7,080
		Business Data for Sales Leads
				66,769
		> Electronics Distribution 0.6%
	3,125,000	Avnet (a)		65,719
		Electronic Components Distribution
				65,719
		> Contract Manufacturing 0.3%
	1,275,000	Plexus (a)		26,086
		Electronic Manufacturing Services
	18,300,000	Sanmina-SCI (a)		8,052
		Electronic Manufacturing Services
				34,138

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Satellite Broadcasting & Services 0.2%
	893,000	SES (France)	$	17,049
		Satellite Broadcasting Services
	250,000	Eutelsat (France)		6,459
		Co-leader in European Fixed Satellite Services
				23,508
		> Consumer Software 0.2%
	3,200,000	THQ (a)		22,912
		Entertainment Software
				22,912
		> Advertising 0.1%
	2,700,000	VisionChina Media - ADR (China) (a)		16,497
		Advertising on Digital Screens in China's Mass Transit System
				16,497
		> Radio —%
	1,541,000	Salem Communications (a)(b)		1,479
		Radio Stations for Religious Programming
	164,991	Saga Communications (a)		850
		Radio Stations in Small & Mid-sized Cities
	2,400,000	Spanish Broadcasting System (a)(b)		432
		Spanish Language Radio Stations
				2,761
		> TV Broadcasting —%
	2,500,000	Entravision Communications (a)		1,200
		Spanish Language TV & Radio Stations
	1,750,000	Gray Television		858
		Mid-market Affiliated TV Stations
				2,058
Information: Total				2,883,929
Industrial Goods & Services 19.4%
		> Machinery 7.8%
	4,500,000	Ametek		155,610
		Aerospace/Industrial Instruments
	4,200,000	Donaldson (b)		145,488
		Industrial Air Filtration
	2,200,000	ESCO Technologies (a)(b)		98,560
		Automatic Electric Meter Readers
	3,000,000	Clarcor (b)		87,570
		Mobile & Industrial Filters
	2,300,000	Pentair		58,926
		Pumps & Water Treatment
	1,975,000	Mine Safety Appliances (b)		47,597
		Safety Equipment
	3,150,000	Oshkosh		45,801
		Specialty Truck Manufacturer
	1,675,000	Pall		44,488
		Filtration & Fluids Clarification
	1,660,000	MOOG (a)		42,845
		Motion Control Products for Aerospace, Defense & Industrial Markets
	1,100,000	Nordson		42,526
		Dispensing Systems for Adhesives & Coatings
	1,300,000	Kaydon		42,328
		Specialized Friction & Motion Control Products

Number of Shares			Value (000)
	1,350,000	Toro	$	40,365
		Turf Maintenance Equipment
	1,225,000	HEICO (b)		35,844
		FAA Approved Aircraft Replacement Parts
	350,000	Lincoln Electric		12,614
		Welding Equipment & Consumables
	114,000	Neopost (France)		10,251
		Postage Meter Machines
	225,000	FreightCar America		3,782
		Coal Railcar Producer
				914,595
		> Industrial Materials & Specialty Chemicals 2.6%
	2,000,000	Sociedad Quimica y Minera de Chile - ADR (Chile)		72,380
		Producer of Specialty Fertilizers, Lithium & Iodine
	1,530,000	Albemarle		39,122
		Refinery Catalysts & Other Specialty Chemicals
	2,200,000	Nalco Holding Company		37,048
		Provider of Water Treatment & Process Chemicals & Services
	363,000	Novozymes (Denmark)		29,504
		Industrial Enzymes
	600,000	Greif		26,532
		Industrial Packaging
	1,600,000	Drew Industries (a)(b)		19,472
		RV & Manufactured Home Components
	15,000	Sika (Switzerland)		16,651
		Chemicals for Construction & Industrial Applications
	2,000,000	Kansai Paint (Japan)		14,319
		Paint Producer in Japan, India, China & Southeast Asia
	515,380	Carbone Lorraine (France)		14,166
		Advanced Industrial Materials
	350,000	Aptargroup		11,819
		Dispensing Systems for Consumer Products & Pharmaceuticals
	450,000	Celanese		10,688
		Commodity & Specialty Chemicals Provider
	350,000	Koppers Holdings		9,230
		Integrated Provider of Carbon Compounds
	743,100	Albany International		8,456
		Paper Machine Clothing & Advanced Textiles
				309,387
		> Other Industrial Services 2.4%
	4,200,000	Expeditors International of Washington		140,028
		International Freight Forwarder
	1,650,000	Forward Air (b)		35,178
		Freight Transportation Between Airports
	1,750,000	Mobile Mini (a)		25,672
		Portable Storage Units Leasing
	2,100,000	UTI Worldwide (a)		23,940
		Freight Forwarding & Logistics
	1,093,050	Imtech (Netherlands)		21,275
		Engineering & Technical Services
	600,000	Intertek Group (United Kingdom)		10,345
		Testing, Inspection & Certification Services

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Other Industrial Services—continued
	900,000	American Reprographics (a)	$	7,488
		Document Management & Logistics
	800,000	TrueBlue (a)		6,720
		Temporary Manual Labor
	615,000	TAL International Group		6,704
		Intermodal Freight Containers Leasing
				277,350
		> Industrial Distribution 2.2%
	2,275,000	Airgas		92,206
		Industrial Gas Distributor
	1,000,000	WW Grainger		81,880
		Industrial Distribution
	900,000	Watsco		44,037
		HVAC Distribution
	2,600,000	Interline Brands (a)(b)		35,568
		Industrial Distribution
				253,691
		> Outsourcing Services 1.5%
	2,300,000	Quanta Services (a)		53,199
		Electrical & Telecom Construction Services
	30,000,000	OLAM International (Singapore)		50,161
		Agriculture Supply Chain Manager
	1,935,000	Administaff (b)		45,027
		Professional Employer Organization
	3,000,000	Serco (United Kingdom)		20,843
		Facilities Management
	600,000	GP Strategies (a)		3,534
		Training Programs
				172,764
		> Construction 1.2%
	700,000	Martin Marietta Materials		55,216
		Aggregates
	1,700,000	Simpson Manufacturing		36,754
		Wall Joint Maker
	60,000	NVR (a)		30,144
		DC Homebuilder
	437,500	Ritchie Brothers Auctioneers (c)		10,259
		Heavy Equipment Auctioneer
	584,000	M/I Homes (a)		5,717
		Columbus-based Home Builder
				138,090
		> Waste Management 0.7%
	1,858,500	Republic Services		45,366
		Solid Waste Management
	1,200,000	Waste Connections (a)		31,092
		Solid Waste Management
				76,458
		> Electrical Components 0.4%
	1,300,000	Acuity Brands		36,465
		Commercial Lighting Fixtures
	1,000,000	Ushio (Japan)		15,947
		Industrial Light Sources
				52,412

Number of Shares			Value (000)
		> Conglomerates 0.3%
	2,869,585	Aalberts Industries (Netherlands)	$	22,578
		Flow Control & Heat Treatment
	600,000	Ibiden (Japan)		16,761
		Electronic Parts & Ceramics
				39,339
		> Steel 0.3%
	1,700,000	GrafTech International (a)		19,227
		Industrial Graphite Materials Producer
	390,000	Haynes International (a)		9,243
		Producer of High Performance Alloys
	450,000	Commercial Metals		7,214
		Vertically Integrated Steelmaker
				35,684
Industrial Goods & Services: Total				2,269,770
Consumer Goods & Services 16.1%
		> Retail 3.9%
	4,020,000	Urban Outfitters (a)		83,897
		Apparel & Home Specialty Retailer
	7,507,000	Chico's FAS (a)		73,043
		Women's Specialty Retailer
	2,505,000	Abercrombie & Fitch		63,602
		Teen Apparel Retailer
	1,964,000	J Crew Group (a)		53,067
		Multi-channel Branded Retailer
	1,061,000	Children's Place Retail Stores (a)		28,042
		Specialty Children's Retailer
	3,308,890	Hot Topic (a)(b)		24,188
		Music Inspired Retailer of Apparel, Accessories & Gifts
	1,800,000	Lululemon Athletica (a)(c)		23,454
		Premium Active Apparel Retailer
	4,250,000	Talbots (b)		22,950
		Women's Specialty Retailer
	1,706,102	Charlotte Russe (a)(b)		21,975
		Value Fashion Retailer
	647,000	GameStop (a)		14,241
		Video Game Specialty Retailer
	3,100,000	Saks (a)		13,733
		Luxury Department Store Retailer
	600,000	Hibbett Sports (a)		10,800
		Sporting Goods Retailer
	2,751,621	Charming Shoppes (a)		10,236
		Women's Specialty Plus Size Apparel Retailer
	1,371,366	Gaiam (a)(b)		7,501
		Healthy Living Catalogs & E-Commerce
	445,700	Bebe Stores		3,067
		Women's Contemporary Specialty Apparel Retailer
	830,444	American Apparel (a)		3,023
		Vertically Integrated Apparel Retailer
				456,819

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Educational Services 2.8%
	1,400,000	ITT Educational Services (a)	$	140,924
		Post-secondary Degree Services
	9,500,000	SkillSoft - ADR (a)(b)		74,100
		Web-based Learning Solutions (E-Learning)
	1,700,000	Career Education (a)		42,313
		Post-secondary Education
	1,750,301	Universal Technical Institute (a)(b)		26,132
		Vocational Training
	386,000	New Oriental Education & Technology - ADR (China) (a)		26,001
		China's Largest Private Education Service Provider
	2,974,300	Princeton Review (a)(b)		16,091
		College Preparation Courses
	2,000,000	Voyager Learning (a)(b)		6,900
		Education Services for the K-12 Market
				332,461
		> Travel 2.4%
	4,700,000	Expedia (a)		71,017
		Online Travel Services Company
	1,950,000	Vail Resorts (a)(b)		52,299
		Ski Resort Operator & Developer
	3,700,000	Gaylord Entertainment (a)(b)		47,027
		Convention Hotels
	1,700,000	Choice Hotels		45,237
		Franchisor of Budget Hotel Brands
	6,000,000	Avis Budget Group (a)(b)		33,900
		Second Largest Car Rental Company
	3,000,000	Hertz (a)		23,970
		Largest U.S. Rental Car Operator
	110,000	Pierre & Vacances (France)		7,653
		Vacation Apartment Lets
				281,103
		> Apparel 1.7%
	5,930,000	Coach		159,398
		Designer & Retailer of Branded Leather Accessories
	1,783,000	True Religion Apparel (a)(b)		39,761
		Premium Denim
				199,159
		> Nondurables 1.4%
	1,010,000	Chattem (a)(b)		68,781
		Personal Care Products
	2,500,000	Jarden (a)		46,875
		Branded Household Products
	1,700,000	Helen of Troy (a)(b)		28,543
		Hair Dryers & Curling Irons
	450,000	Energizer Holdings (a)		23,508
		Household & Personal Care Products
				167,707
		> Furniture & Textiles 1.1%
	3,500,000	Herman Miller (b)		53,690
		Office Furniture
	4,000,000	Knoll (b)		30,320
		Office Furniture
	1,245,000	HNI		22,485
		Office Furniture & Fireplaces

Number of Shares			Value (000)
	2,016,856	Steelcase	$	11,738
		Office Furniture
	646,780	Interface		4,010
		Modular & Broadloom Carpet
				122,243
		> Food & Beverage 0.6%
	1,600,000	Hansen Natural (a)		49,312
		Alternative Beverages
	2,500,000	Smart Balance (a)		17,025
		Healthy Food Products
				66,337
		> Casinos & Gaming 0.5%
	4,050,000	Pinnacle Entertainment (a)(b)		37,625
		Regional Casino Operator
	875,000	Penn National Gaming (a)		25,471
		Regional Casino Operator
				63,096
		> Leisure Products 0.4%
	1,390,000	Thor Industries		25,534
		RV & Bus Manufacturer
	1,416,000	Speedway Motorsports		19,484
		Motorsports Racetrack Owner & Operator
	850,000	Winnebago Industries		6,316
		Motor Home Maker
				51,334
		> Consumer Goods Distribution 0.4%
	2,600,000	Pool (b)		43,056
		Distributor of Swimming Pool Supplies & Equipment
	110,010	Central European Distribution (Poland) (a)		2,923
		Vodka Production & Spirits Distribution
				45,979
		> Other Consumer Services 0.4%
	1,900,000	Lifetime Fitness (a)(c)		38,019
		Sport & Fitness Club Operator
	3,381,400	Lifestyle International (Hong Kong)		4,397
		Mid to High-end Department Store Operator in Hong Kong & China
				42,416
		> Restaurants 0.3%
	550,000	P.F. Chang's China Bistro (a)		17,633
		Mandarin Style Restaurants
	2,000,000	AFC Enterprises (a)(b)		13,500
		Popeye's Restaurants
				31,133
		> Other Entertainment 0.2%
	435,000	CTS Eventim (Germany)		17,620
		Event Ticket Sales
				17,620
		> Other Durable Goods —%
	4,500,000	Champion Enterprises (a)(b)		1,440
		Manufactured Homes
				1,440
Consumer Goods & Services: Total				1,878,847

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
Finance 13.0%
		> Insurance 3.4%
	2,400,000	Assurant	$	57,816
		Specialty Insurance
	2,365,000	HCC Insurance Holdings		56,784
		Specialty Insurance
	1,300,000	Endurance Specialty Holdings		38,090
		Commercial Lines Insurance/Reinsurance
	1,748,000	Leucadia National (a)		36,865
		Insurance Holding Company
	1,450,000	Delphi Financial Group		28,174
		Workers Compensation & Group Employee Benefit Products & Services
	100,000	Markel (a)		28,170
		Specialty Insurance
	575,000	Navigators Group (a)		25,547
		Specialty Insurance
	1,000,000	Aspen Insurance		22,340
		Commercial Lines Insurance/Reinsurance
	9,420,000	Conseco (a)(b)		22,326
		Life, Long-term Care & Medical Supplement Insurance
	900,000	Tower Group		22,302
		Commercial & Personal Lines Insurance
	832,000	Willis Group		21,407
		Insurance Broker
	1,420,000	Selective Insurance Group		18,133
		Commercial & Personal Lines Insurance
	1,200,000	SeaBright Insurance Holdings (a)(b)		12,156
		Workers Compensation Insurance
	995,000	Protective Life		11,383
		Life Insurance
				401,493
		> Banks 3.3%
	3,000,000	BOK Financial		113,010
		Tulsa-based Southwest Bank
	4,150,000	TCF Financial		55,485
		Great Lakes Bank
	4,538,205	Valley National Bancorp		53,097
		New Jersey/New York Bank
	3,337,900	Associated Banc-Corp		41,724
		Midwest Bank
	1,160,000	SVB Financial Group (a)		31,575
		Bank to Venture Capitalists
	1,690,000	Wilmington Trust		23,085
		Delaware Trust Bank
	2,020,000	MB Financial (b)		20,584
		Chicago Bank
	1,200,000	TriCo Bancshares (b)		18,600
		California Central Valley Bank
	250,000	Cullen/Frost Bankers		11,530
		Texas Bank
	170,000	City National		6,261
		Bank & Asset Manager
	178,550	Sandy Spring Bancorp		2,625
		Baltimore, D.C. Bank
	1,000,000	West Coast Bancorp (b)		2,040
		Portland Community Bank

Number of Shares			Value (000)
	341,296	Green Bankshares	$	1,529
		Tennessee Bank
				381,145
		> Finance Companies 2.5%
	7,235,000	AmeriCredit (a)(b)(c)		98,034
		Auto Lending
	1,730,000	GATX		44,495
		Rail Car Lessor
	2,266,361	McGrath Rentcorp (b)		43,197
		Temporary Space & IT Rentals
	3,300,000	H&E Equipment Services (a)(b)		30,855
		Heavy Equipment Leasing
	1,545,000	World Acceptance (a)(b)		30,761
		Personal Loans
	655,000	Aaron's		19,532
		Rent to Own
	7,000,000	CIT Group		15,050
		Middle Market Lender, Equipment Leasing & Vendor Finance/Factoring
	1,650,000	CAI International (a)(b)		8,415
		International Container Leasing
	1,091,000	Marlin Business Services (a)(b)		6,110
		Small Equipment Leasing
				296,449
		> Brokerage & Money Management 2.1%
	6,448,000	SEI Investments		116,322
		Mutual Fund Administration & Investment Management
	4,235,000	Eaton Vance		113,286
		Specialty Mutual Funds
	700,000	Investment Technology Group (a)		14,273
		Electronic Trading
	550,000	Cohen & Steers (c)		8,223
		REIT Fund Manager
				252,104
		> Savings & Loans 1.7%
	8,563,899	People's United		128,801
		Connecticut Savings & Loan
	1,989,000	Washington Federal		25,857
		Savings & Loan
	450,000	Housing Development Finance (India)		22,075
		Indian Mortgage Lender
	500,000	ViewPoint Financial		7,615
		Texas Thrift
	660,000	Provident New York Bancorp		5,359
		New York State Thrift
	234,693	Berkshire Hills Bancorp		4,877
		Northeast Thrift
				194,584
Finance: Total				1,525,775
Health Care 11.7%
		> Medical Equipment & Devices 3.6%
	3,000,000	Alexion Pharmaceuticals (a)		123,360
		Biotech Focused on Orphan Diseases
	2,100,000	Illumina (a)		81,774
		Leading Tools & Service Provider for Genetic Analysis

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Medical Equipment & Devices—continued
	750,000	Edwards Lifesciences (a)	$	51,022
		Heart Valves
	700,000	Haemonetics (a)		39,900
		Blood & Plasma Collection Equipment
	2,400,000	American Medical Systems (a)		37,920
		Medical Devices to Treat Urological Conditions
	1,900,000	Hologic (a)		27,037
		Diagnostic & Medical Imaging Equipment for Women's Health
	900,000	Kinetic Concepts (a)		24,525
		Wound Healing & Tissue Repair Products
	300,000	Beckman Coulter		17,142
		In-vitro Clinical Diagnostics
	600,000	Orthofix International (a)		15,006
		Bone Fixation & Stimulation Devices
				417,686
		> Biotechnology & Drug Delivery 3.2%
	2,000,000	Myriad Genetics (a)		71,300
		Genetic Diagnostics
	1,660,000	Auxilium Pharmaceuticals (a)		52,091
		Biotech Focused on Niche Disease Areas
	3,000,000	BioMarin (a)		46,830
		Biotech Focused on Orphan Diseases
	4,800,000	Medarex (a)		40,080
		Humanized Antibodies
	3,834,516	Seattle Genetics (a)		37,271
		Antibody-based Therapies for Cancer
	400,000	United Therapeutics (a)		33,332
		Biotech Focused on Rare Diseases
	4,631,195	Nektar Therapeutics (a)(b)		30,010
		Drug Delivery Technologies
	2,000,000	Savient Pharmaceuticals (a)		27,720
		Biotech Company Focused on Niche Disease Areas
	1,781,707	InterMune (a)		27,082
		Drugs for Pulmonary Fibrosis & Hepatitis C
	669,465	NPS Pharmaceuticals (a)		3,119
		Orphan Drugs & Healthy Royalties
	97,275	Poniard (a)		581
		Cancer Biotech
	359,944	MicroDose Technologies (a)(d)		198
		Drug Inhaler Development
	1,249,999	Perlegen Sciences (a)(d)		25
		Large Scale Gene Sequencing
	187,500	Locus Pharmaceuticals, Series A-1, Pfd. (a)(d)		15
	96,644	Locus Pharmaceuticals, Series B-1, Pfd. (a)(d)		8
		High Throughput Rational Drug Design
				369,662
		> Medical Supplies 2.6%
	1,090,000	Henry Schein (a)		52,265
		Largest Distributor of Healthcare Products
	2,453,000	Luminex (a)(b)		45,479
		Life Science Tools & Molecular Diagnostics
	4,000,000	Cepheid (a)(b)		37,680
		Molecular Diagnostics

Number of Shares			Value (000)
	850,000	ICU Medical (a)(b)	$	34,978
		Intravenous Therapy Products
	1,675,000	QIAGEN (Netherlands) (a)		31,138
		Life Science Tools & Molecular Diagnostics
	486,000	Techne		31,012
		Cytokines, Antibodies & Other Reagents for Life Science
	665,000	Idexx Laboratories (a)		30,723
		Diagnostic Equipment & Services for Veterinarians
	700,000	Cooper		17,311
		Contact Lens Manufacturer
	900,000	Immucor (a)		12,384
		Automated Blood Typing Reagents
	150,000	Owens & Minor		6,573
		Distribution of Medical Supplies
				299,543
		> Health Care Services 1.8%
	2,200,000	Psychiatric Solutions (a)		50,028
		Behavioral Health Services
	1,050,000	Charles River Laboratories (a)		35,437
		Pharmaceutical Research
	1,847,035	PSS World Medical (a)		34,189
		Distributor of Medical Supplies
	700,000	MEDNAX (a)		29,491
		Physician Management for Pediatric & Anesthesia Practices
	4,250,000	eResearch Technology (a)(b)		26,393
		Clinical Research Services
	975,300	Rhoen-Klinikum (Germany)		21,566
		Health Care Services
	850,000	Healthcare Services Group		15,198
		Outsourced Services to Long-term Care Industry
				212,302
		> Pharmaceuticals 0.5%
	1,000,000	Cephalon (a)		56,650
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	2,450,000	United Drug (Ireland)		6,806
		Irish Pharmaceutical Wholesaler & Outsourcer
	151,531	Myriad Pharmaceuticals (a)		705
		Genetic Diagnostics
				64,161
Health Care: Total				1,363,354
Energy & Minerals 8.3%
		> Oil Services 3.9%
	2,809,568	Fugro (Netherlands)		116,666
		Sub-sea Oilfield Services
	3,100,000	FMC Technologies (a)		116,498
		Oil & Gas Wellhead Manufacturer
	3,200,000	Atwood Oceanics (a)		79,712
		Offshore Drilling Contractor
	1,000,000	Oceaneering International (a)		45,200
		Provider of Sub-sea Services & Manufactured Products
	1,670,000	ShawCor (Canada)		28,902
		Oil & Gas Pipeline Products

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Oil Services—continued
	4,870,800	Trinidad Drilling (Canada)	$	20,603
		Operator of Deep Land Drilling Rigs & Service Rigs throughout North America
	1,750,000	Tesco (a)		13,895
		Developing New Well Drilling Technologies
	375,000	Bristow (a)		11,111
		Largest Provider of Helicopter Services to Offshore Oil & Gas Producers
	1,198,000	Tetra Technologies (a)		9,536
		U.S.-based Service Company with Life of Field Approach
	502,000	Exterran Holdings (a)		8,052
		Natural Gas Compressor Rental & Fabrication
	2,983,500	Horizon North Logistics (Canada) (a)		2,693
		Provides Diversified Oil Service Offering in Northern Canada
				452,868
		> Oil & Gas Producers 3.8%
	3,600,000	Southwestern Energy (a)		139,860
		Oil & Gas Producer
	1,850,000	XTO Energy		70,559
		Oil & Gas Producer
	1,100,000	Range Resources		45,551
		Oil & Gas Producer
	5,110,550	Pacific Rubiales Energy (Canada) (a)		42,136
		Oil Production & Exploration in Colombia
	975,000	Ultra Petroleum (a)		38,025
		Oil & Gas Producer
	2,400,000	Tullow Oil (United Kingdom)		37,131
		Oil & Gas Producer
	1,400,000	Carrizo Oil & Gas (a)		24,010
		Oil & Gas Producer
	1,400,000	Denbury Resources (a)		20,622
		Oil Producer Using Co2 Injection
	4,000,000	Gran Tierra Energy (Canada) (a)		13,927
		Oil Exploration & Production in Colombia, Peru & Argentina
	1,200,000	TriStar Oil & Gas (Canada) (a)		11,338
		Canadian Oil & Gas Producer
	1,500,000	Vaalco Energy (a)		6,345
		Oil & Gas Producer
				449,504
		> Mining 0.5%
	2,700,000	Silver Wheaton (Canada) (a)		22,248
		Silver Mining Royalty Company
	7,725,000	Uranium One (South Africa) (a)		17,733
		Uranium Mines in Kazakhstan, the U.S. & Australia
	300,000	Royal Gold		12,510
		Precious Metals Mining Royalty Company
	1,000,000	Ivanhoe Mines (Canada) (a)		5,545
		Copper Mine Project in Mongolia
				58,036
		> Oil Refining, Marketing & Distribution 0.1%
	435,000	Oneok		12,828
		Natural Gas Distribution, Pipeline Processing & Trading
				12,828

Number of Shares			Value (000)
		> Alternative Energy —%
	1,800,000	Synthesis Energy Systems (China) (a)	$	2,070
		Owner/Operator of Gasification Plants
				2,070
Energy & Minerals: Total				975,306
Other Industries 4.1%
		> Real Estate 2.2%
	675,000	Federal Realty Investment Trust		34,776
		Shopping Centers
	850,000	Digital Realty Trust		30,473
		Technology-focused Office Buildings
	900,000	Corporate Office Properties		26,397
		Office Buildings
	900,000	American Campus Communities		19,962
		Student Housing
	1,065,000	Macerich Company (c)		18,755
		Regional Shopping Malls
	750,000	SL Green Realty		17,205
		Manhattan Office Buildings
	700,000	Washington REIT		15,659
		Washington D.C. Diversified Properties
	3,750,000	DCT Industrial Trust		15,300
		Industrial Properties
	40,000,000	Mapletree Logistics (Singapore)		15,263
		Asian Logistics Landlord
	13,069,100	Ascendas REIT (Singapore)		14,306
		Singapore Industrial Property Landlord
	1,360,000	BioMed Realty Trust		13,913
		Life Science-focused Office Buildings
	2,800	Orix JREIT (Japan)		12,817
		Diversified REIT
	1,400,000	Extra Space Storage		11,690
		Self Storage Facilities
	1,158,000	Forest City Enterprises, Class B (b)		7,515
		Commercial & Residential Property Developer
	2,300,000	Kite Realty Group		6,716
		Community Shopping Centers
	37,407	Security Capital European Realty (Luxembourg) (a)(d)(e)		—
		Self Storage Properties
				260,747
		> Transportation 1.3%
	2,110,000	JB Hunt Transport Services		64,418
		Truck & Intermodal Carrier
	2,480,000	Heartland Express		36,506
		Regional Trucker
	2,500,000	Rush Enterprises, Class A (a)(b)		29,125
	500,000	Rush Enterprises, Class B (a)(b)		4,955
		Truck Sales & Services
	625,000	American Commercial Lines (a)		9,675
		Operator of Inland Barges/Builder of Barges & Vessels
	200,000	World Fuel Services		8,246
		Global Fuel Broker
				152,925

See accompanying notes to financial statements.

Number of Shares or Principal Amount (000)			Value (000)
		> Regulated Utilities 0.6%
	1,800,000	Northeast Utilities	$	40,158
		Regulated Electric Utility
	536,000	Red Electrica de Espana (Spain)		24,251
		Spanish Power Grid
				64,409
Other Industries: Total				478,081
Total Equities: 97.3% (Cost: $10,546,278)				11,375,062
Securities Lending Collateral: 1.1%
	133,395,450	Dreyfus Government Cash Management Fund (f) (7 day yield of 0.150%)		133,395
Total Securities Lending Collateral: (Cost: $133,395)				133,395
Short-Term Obligations: 2.9%
		> Repurchase Agreement 2.5%
$	291,659	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.0001%, collateralized by U.S. Treasury obligations with various maturities to 8/17/17, market value $297,497 (repurchase proceeds $291,659)		291,659
				291,659
		> Commercial Paper 0.4%
	50,000	Toyota Motor Credit 0.26% due 7/06/09		49,998
				49,998
Total Short-Term Obligations: (Amortized Cost: $341,657)				341,657
Total Investments: 101.3% (Cost: $11,021,330)(g)(h)				11,850,114
Obligation to Return Collateral for Securities Loaned: (1.1)%				(133,395	)
Cash and Other Assets Less Liabilities: (0.2)%				(22,925	)
Total Net Assets: 100.0%			$	11,693,794

ADR = American Depositary Receipts.

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

> Notes to Statement of Investments (dollar values in thousands)

(a) Non-income producing security.

Affiliates	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 6/30/09		Value		Dividend
Actuate		1,683,760		1,102,043		-		2,785,803	$	13,316	$	-
Administaff		2,025,000		-		90,000		1,935,000		45,027		527
AFC Enterprises		1,800,000		200,000		-		2,000,000		13,500		-
AmeriCredit		7,235,000		-		-		7,235,000		98,034		-
Array Biopharma*		2,910,000		-		2,910,000		-		-		-
Avis Budget Group		-		6,000,000		-		6,000,000		33,900		-
Bally Technologies		3,750,000		275,000		-		4,025,000		120,428		-
CAI International		1,500,000		150,000		-		1,650,000		8,415		-
Carrizo Oil & Gas*		2,525,000		200,000		1,325,000		1,400,000		24,010		-
Cepheid		3,100,000		900,000		-		4,000,000		37,680		-
Champion Enterprises		4,500,000		-		-		4,500,000		1,440		-
Charlotte Russe		-		1,706,102		-		1,706,102		21,975		-
Chattem		1,010,000		-		-		1,010,000		68,781		-
Clarcor		3,000,000		-		-		3,000,000		87,570		540
Cogent Communications		4,300,000		-		-		4,300,000		35,045		-
Conseco		9,420,000		-		-		9,420,000		22,326		-
Donaldson		4,200,000		-		-		4,200,000		145,488		966
Drew Industries		1,324,000		276,000		-		1,600,000		19,472		-
Entravision Communications*		2,500,000		-		-		2,500,000		1,200		-
eResearch Technology		3,935,901		314,099		-		4,250,000		26,393		-
ESCO Technologies		2,200,000		-		-		2,200,000		98,560		-
FARO Technologies		1,275,000		-		221,035		1,053,965		16,368		-
Forest City Enterprises, Class B		1,158,000		-		-		1,158,000		7,515		-
Forward Air		1,900,000		-		250,000		1,650,000		35,178		231
Gaiam		1,200,000		171,366		-		1,371,366		7,501		-
Gaylord Entertainment		3,300,000		400,000		-		3,700,000		47,027		-
H&E Equipment Services		3,300,000		-		-		3,300,000		30,855		-
Hackett Group		4,600,000		-		100,000		4,500,000		10,485		-
HEICO		850,000		375,000		-		1,225,000		35,844		51
Helen of Troy		1,900,000		-		200,000		1,700,000		28,543		-
Herman Miller		3,000,000		500,000		-		3,500,000		53,690		528
Hot Topic		-		3,791,890		483,000		3,308,890		24,188		-
ICU Medical		1,250,000		-		400,000		850,000		34,978		-
iGate		5,000,000		-		-		5,000,000		33,100		550
II-VI		2,400,000		-		-		2,400,000		53,208		-
Informatica		5,500,000		1,200,000		-		6,700,000		115,173		-
Interline Brands		2,000,000		600,000		-		2,600,000		35,568		-
IPG Photonics		2,750,000		-		-		2,750,000		30,167		-
ITT Educational Services*		2,150,000		-		750,000		1,400,000		140,924		-
IXYS		2,035,000		100,000		-		2,135,000		21,606		-
Kenexa		2,425,000		-		-		2,425,000		28,057		-
Kite Realty Group*		1,900,000		400,000		-		2,300,000		6,716		740
Knoll		3,300,000		700,000		-		4,000,000		30,320		476
Luminex		1,110,000		1,343,000		-		2,453,000		45,479		-
Marlin Business Services		1,091,000		-		-		1,091,000		6,110		-
MB Financial		2,020,000		-		-		2,020,000		20,584		263
McGrath Rentcorp		1,890,000		376,361		-		2,266,361		43,197		838
Mediacom Communications		4,000,000		-		344,085		3,655,915		18,682		-
Mine Safety Appliances		1,975,000		-		-		1,975,000		47,597		948
Mobile Mini*		1,750,000		-		-		1,750,000		25,672		-
Navigant Consulting		2,500,000		-		-		2,500,000		32,300		-
Nektar Therapeutics		5,325,000		-		693,805		4,631,195		30,010		-
PAETEC Holdings		8,000,000		165,000		-		8,165,000		22,045		-
Pericom Semiconductor		915,000		850,000		-		1,765,000		14,861		-
Pinnacle Entertainment		4,050,000		-		-		4,050,000		37,625		-
Pool		2,600,000		-		-		2,600,000		43,056		676
Princeton Review		2,550,000		424,300		-		2,974,300		16,091		-
Quality Systems*		1,850,000		-		700,000		1,150,000		65,504		975

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

Affiliates	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 6/30/09		Value		Dividend
Radiant Systems		3,050,000		-		-		3,050,000	$	25,315	$	-
Rush Enterprises		2,750,000		250,000		-		3,000,000		34,080		-
Salem Communications		1,541,000		-		-		1,541,000		1,479		-
Savient Pharmaceuticals*		1,416,941		1,583,059		1,000,000		2,000,000		27,720		-
SeaBright Insurance Holdings		1,200,000		-		-		1,200,000		12,156		-
Seattle Genetics*		4,400,000		-		565,484		3,834,516		37,271		-
SkillSoft - ADR		9,500,000		-		-		9,500,000		74,100		-
Smart Balance*		5,000,000		-		2,500,000		2,500,000		17,025		-
Spanish Broadcasting System		2,400,000		-		-		2,400,000		432		-
Stewart Information Services*		909,420		-		909,420		-		-		-	��
Stratasys*		1,180,000		-		235,900		944,100		10,376		-
Supertex		1,035,000		-		-		1,035,000		25,989		-
Switch & Data Facilities		2,500,000		-		-		2,500,000		29,325		-
Talbots		4,250,000		-		-		4,250,000		22,950		-
TriCo Bancshares		1,200,000		-		-		1,200,000		18,600		312
True Religion Apparel		1,150,000		633,000		-		1,783,000		39,761		-
tw telecom		9,500,000		-		-		9,500,000		97,565		-
Universal Technical Institute		1,500,000		250,301		-		1,750,301		26,132		-
Vail Resorts		2,390,000		-		440,000		1,950,000		52,299		-
Viad*		1,032,075		-		1,032,075		-		-		73
Virtusa		1,000,000		450,000		-		1,450,000		11,644		-
Voyager Learning		2,000,000		-		-		2,000,000		6,900		-
West Coast Bancorp		837,000		163,000		-		1,000,000		2,040		18
World Acceptance		1,545,000		-		-		1,545,000		30,761		-
TOTAL OF AFFILIATED TRANSACTIONS		221,024,097		25,849,521		15,149,804		231,723,814	$	2,822,304	$	8,712

* At June 30, 2009, the Fund owned less than five percent of the company's outstanding voting shares.

(c) All or a portion of this security was on loan at June 30, 2009. The total market value of securities on loan at June 30, 2009 was $129,784.

Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
MicroDose Technologies	11/24/00		359,944	$	2,005	$	198
Perlegen Sciences	3/30/01		1,249,999		4,500		25
Locus Pharmaceuticals, Series A-1, Pfd.	9/05/01		187,500		7,500		15
Locus Pharmaceuticals, Series B-1, Pfd.	2/08/07		96,644		280		8
Security Capital European Realty	8/20/98-7/20/99		37,407		205		-
				$	14,490	$	246

(e) Security has no value.

(f) Investment made with cash collateral received from securities lending activity.

(h) On June 30, 2009, the market value of foreign securities represented 9.52% of total net assets. The Fund's foreign portfolio was diversified as follows:

	Value		Percentage of Net Assets
Netherlands	$	191,657		1.64
Canada		147,392		1.26
Singapore		128,585		1.10
Japan		110,684		0.95
Chile		72,380		0.62
United Kingdom		68,319		0.58
France		55,578		0.48
Sweden		47,045		0.40
China		44,568		0.38
Germany		39,186		0.34
Hong Kong		37,392		0.32
	Value		Percentage of Net Assets
Denmark	$	29,504		0.25
India		28,373		0.24
South Korea		25,977		0.22
Spain		24,251		0.21
Israel		18,456		0.16
South Africa		17,733		0.15
Switzerland		16,651		0.14
Ireland		6,806		0.06
Poland		2,923		0.02
Luxembourg		-		-
Total Foreign Portfolio	$	1,113,460		9.52

See accompanying notes to financial statements.

Columbia Acorn Fund

Statement of Investments (Unaudited), continued

> Notes to Statement of Investments (dollar values in thousands)

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Equities
Total Information	$	2,654,709	$	229,220	$	-	$	2,883,929
Total Industrial Goods & Services		2,026,969		242,801		-		2,269,770
Total Consumer Goods & Services		1,802,150		29,670		-		1,831,820
Total Finance		1,503,700		22,075		-		1,525,775
Total Health Care		1,334,736		28,372		246		1,363,354
Total Energy & Minerals		821,509		153,797		-		975,306
Total Other Industries		458,471		66,637		-		525,108
Total Equities		10,602,244		772,572		246		11,375,062
Securities Lending Collateral		133,395		-		-		133,395
Short-Term Obligations		-		341,657		-		341,657
Total Investments		10,735,639		1,114,229		246		11,850,114
Total	$	10,735,639	$	1,114,229	$	246	$	11,850,114

The Fund's assets assigned to the Level 2 input category include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation.

Investments in Secruities	Balance as of December 31, 2008		Accrued Discounts/ Premiums		Realized Gain/(Loss)		Change in Unrealized Appreciation (Depreciation)			Net Purchases		Net Sales		Net transfers into Level 3		Net transfers out of Level 3		Balance as of June 30, 2009		Change in Unrealized Appreciation (Depreciation) from Investments held at June 30, 2009
Health Care
Biotechnology & Drug Delivery	$	426	$	-	$	-	$	(180	)	$	-	$	-	$	-	$	-	$	246	$	(180	)
Other Industries
Real Estate*		-		-		-		-			-		-		-		-		-		-
Total	$	426	$	-	$	-	$	(180	)	$	-	$	-	$	-	$	-	$	246	$	(180	)

* Security Capital European Realty has no value.

See accompanying notes to financial statements.

Columbia Acorn International

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Asia
> Japan
Aeon Delight		1,066,100		1,243,900
Aeon Mall		880,000		1,354,000
Asics		1,748,100		2,143,500
Benesse		286,900		398,900
Daiseki		755,700		787,200
Point		418,760		519,570
Rohto Pharmaceutical		1,250,000		1,735,100
Zenrin		600,000		743,100
> China
Mindray - ADR		797,000		833,800
New Oriental Education & Technology - ADR		223,000		382,000
RexLot Holdings		151,000,000		250,000,000
Shandong Weigao		2,625,000		4,800,000
> Singapore
Ascendas REIT		0		9,821,100
Mapletree Logistics		70,000,000		76,413,000
OLAM International		27,500,000		30,000,000
Singapore Exchange		6,900,000		7,000,000
> India
Educomp Solutions		250,000		370,000
Shriram Transport Finance		1,600,000		2,135,000
> South Korea
Mirae Asset Securities		0		376,000
NHN		94,000		245,000
> Taiwan
President Chain Store		6,996,000		9,994,000
Simplo Technology		0		3,655,000
Yuanta FHC		0		45,000,000
> Hong Kong
Lifestyle International		19,000,000		20,668,600
Europe
> United Kingdom
Chemring		275,000		384,000
Cobham		3,050,000		4,434,000
N Brown Group		0		2,730,000
Serco		5,100,000		5,500,000
> Netherlands
Aalberts Industries		1,992,322		2,051,535
Fugro		628,000		661,945
Smit Internationale		228,993		244,969
Vopak		372,000		390,900
> Germany
Tognum		656,900		744,400

	Number of Shares
	03/31/09		06/30/09
> France
Carbone Lorraine		309,390		399,598
Eutelsat		0		393,000
Neopost		198,000		295,000
Pierre & Vacances		171,700		222,118
Rubis		139,900		155,900
SAFT		322,000		441,635
> Sweden
East Capital Explorer		0		750,000
> Italy
CIR		12,866,000		15,569,356
Credito Emiliano		1,500,000		2,045,000
> Denmark
Novozymes		130,000		297,000
> Spain
Red Electrica de Espana		440,000		532,000
Other Countries
> United States
Alexion Pharmaceuticals		350,000		475,000
Atwood Oceanics		1,290,000		1,340,000
Illumina		0		150,000
Ritchie Brothers Auctioneers		0		150,000
World Fuel Services		0		200,000
> Canada
CCL Industries		819,000		1,117,000
Ivanhoe Mines		0		744,000
> Australia
Cochlear		0		70,000
> South Africa
Naspers		1,723,000		1,973,000
Latin America
> Brazil
Localiza Rent A Car		5,156,000		5,500,000
Natura		1,500,000		2,000,000
> Mexico
Grupo Aeroportuario del Sureste - ADR		600,000		700,000

See accompanying notes to financial statements.

Columbia Acorn International

Major Portfolio Changes in the Second Quarter (Unaudited), continued

	Number of Shares
	03/31/09		06/30/09
Sales
Asia
> Japan
Jupiter Telecommunications		43,500		31,500
Makita		540,000		430,000
Cosel		882,000		0
NGK Insulators		690,000		0
Ryohin Keikaku		288,000		0
SYSMEX		231,000		0
T. Hasegawa		538,000		0
Union Tool		247,200		0
Yusen Air & Sea Service		614,400		0
> China
Jiangsu Expressway		28,896,000		20,563,000
Hopewell Highway Infrastructure		17,098,900		0
Sinotrans		34,508,800		0
> Singapore
ComfortDelGro		18,060,000		0
> India
United Phosphorus		8,900,000		3,449,517
> South Korea
Taewoong		360,000		298,000
Woongjin Coway		1,112,000		753,000
> Hong Kong
Hong Kong Exchanges and Clearing		3,000,000		2,700,000
Hong Kong Aircraft Engineering		709,100		0
Europe
> United Kingdom
Intermediate Capital		900,000		864,000
Randgold Resources - ADR		400,000		212,000
> Netherlands
Imtech		2,025,000		1,871,250
QIAGEN		850,000		650,000
> Germany
Rational		175,143		155,000
Rhoen-Klinikum		1,607,845		1,010,947
> France
Iliad		250,000		211,000
Norbert Dentressangle		216,215		160,701
SES		1,447,000		944,000
> Switzerland
Geberit		200,000		167,000
Kuehne & Nagel		317,000		275,000

	Number of Shares
	03/31/09		06/30/09
> Sweden
Hexagon		4,733,000		3,944,000
> Italy
Sabaf		115,295		0
> Poland
ING Bank Slaski		44,162		0
> Greece
Intralot		5,090,000		3,427,000
> Russia
Novolipetsk Steel - GDR		775,000		0
Other Countries
> United States
FMC Technologies		410,000		251,000
> South Africa
Impala Platinum Holdings		1,440,000		0
> New Zealand
Sky City Entertainment		6,320,612		868,418
Latin America
> Brazil
Porto Seguro		2,500,000		0
> Chile
Sociedad Quimica y Minera de Chile - ADR		1,129,000		862,000

See accompanying notes to financial statements.

Columbia Acorn International

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 94.4%
Asia 42.6%
		> Japan 18.4%
	6,550,000	Kansai Paint	$	46,895
		Paint Producer in Japan, India, China & Southeast Asia
	11,371	Nippon Residential Investment		27,963
		Residential REIT
	519,570	Point		27,895
		Apparel Specialty Retailer
	10,170	Seven Bank		26,592
		ATM Processing Services
	1,354,000	Aeon Mall		25,621
		Suburban Shopping Mall Developer, Owner & Operator
	3,000,000	Kamigumi		25,254
		Port Cargo Handling & Logistics
	31,500	Jupiter Telecommunications		23,882
		Largest Cable Service Provider in Japan
	4,300	Osaka Securities Exchange		20,490
		Osaka Securities Exchange
	1,243,900	Aeon Delight		20,095
		Facility Maintenance & Management
	1,735,100	Rohto Pharmaceutical		19,576
		Health & Beauty Products
	2,143,500	Asics		19,462
		Footwear & Apparel
	4,200	Orix JREIT		19,226
		Diversified REIT
	925,200	Glory		18,303
		Currency Handling Systems & Related Equipment
	640,000	Ibiden		17,878
		Electronic Parts & Ceramics
	737,000	Kintetsu World Express		17,504
		Airfreight Logistics
	787,200	Daiseki		17,284
		Waste Disposal & Recycling
	1,750,000	Suruga Bank		16,680
		Regional Bank
	553,400	Unicharm PetCare		16,520
		Pet Food & Pet Toiletries
	1,900	Nippon Building Fund		16,261
		Office REIT
	398,900	Benesse		15,943
		Education Service Provider
	950,000	Ushio		15,150
		Industrial Light Sources
	7,500	Wacom		15,135
		Computer Graphic Illustration Devices
	193,000	Nakanishi		14,187
		Dental Tools & Machinery
	3,050	Fukuoka		13,672
		Diversified REIT in Fukuoka
	643,000	Ain Pharmaciez (a)		13,332
		Dispensing Pharmacy/Drugstore Operator
	587,800	Miura		13,094
		Industrial Boiler

Number of Shares			Value (000)
	3,100,000	Chuo Mitsui Trust Holdings	$	11,765
		Trust Bank
	480,000	Olympus		11,279
		Medical Equipment (Endoscopes) & Cameras
	580,000	Hamamatsu Photonics		11,056
		Optical Sensors for Medical & Industrial Applications
	743,100	Zenrin		10,982
		Map Content Publisher
	785,000	Tamron		10,704
		Camera Lens Maker
	430,000	Makita		10,356
		Power Tools
	1,650	Nippon Accommodations Fund		7,405
		Residential REIT
	407,200	As One		7,290
		Scientific Supplies Distributor
	116,300	Toyo Tanso		4,433
		Carbon & Graphite Products for Industrial Use
	115,000	Tsumura		3,583
		Traditional Chinese/Japanese Herbal Rx Drugs (Kampo)
				612,747
		> China 5.7%
	29,166,400	China Green		30,605
		Chinese Fruit & Vegetable Grower & Processor
	382,000	New Oriental Education & Technology - ADR (b)		25,731
		China's Largest Private Education Service Provider
	833,800	Mindray - ADR		23,280
		Medical Device Manufacturer
	14,182,000	China Yurun Food		21,353
		Meat Processor in China
	250,000,000	RexLot Holdings (b)		19,661
		Lottery Equipment Supplier in China
	13,414,000	China Shipping Development		17,114
		China's Dominant Shipper for Oil & Coal
	20,563,000	Jiangsu Expressway		15,065
		Chinese Toll Road Operator
	15,300,000	Fu Ji Food & Catering Services		12,858
		Food Catering Service Provider in China
	4,800,000	Shandong Weigao		12,300
		Vertically Integrated Hospital Consumable Manufacturer
	1,000,000	VisionChina Media - ADR (b)		6,110
		Advertising on Digital Screens in China's Mass Transit System
	282,500	ZhongDe Waste Technology		5,130
		Solid Municipal Waste & Medical Waste Incinerator Manufacturer
				189,207
		> Singapore 4.2%
	30,000,000	OLAM International		50,161
		Agriculture Supply Chain Manager
	7,000,000	Singapore Exchange		34,199
		Singapore Equity & Derivatives Market Operator

See accompanying notes to financial statements.

Columbia Acorn International

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Singapore—continued
	76,413,000	Mapletree Logistics	$	29,157
		Asian Logistics Landlord
	30,000,000	CDL Hospitality Trust		17,112
		Hotel Owner/Operator
	9,821,100	Ascendas REIT		10,751
		Singapore Industrial Property Landlord
				141,380
		> India 4.2%
	370,000	Educomp Solutions (b)		29,044
		Multimedia Educational Content
	1,008,727	Asian Paints		24,675
		India's Largest Paint Company
	1,700,000	Jain Irrigation Systems		22,413
		Agricultural Micro-irrigation Systems & Food Processing
	450,000	Housing Development Finance (b)		22,075
		Indian Mortgage Lender
	1,350,000	Mundra Port & Special Economic		17,180
		Zone Indian West Coast Shipping Port
	2,135,000	Shriram Transport Finance		13,529
		Truck Financing in India
	3,449,517	United Phosphorus		10,350
		Off-patent Crop Protection Chemicals
				139,266
		> South Korea 3.9%
	245,000	NHN (b)		33,853
		South Korea's Largest Online Search Engine
	158,000	MegaStudy		28,440
		Online Education Service Provider
	298,000	Taewoong		20,955
		Niche Custom Forging
	376,000	Mirae Asset Securities		20,368
		South Korean Largest Diversified Financial Company
	753,000	Woongjin Coway		18,272
		South Korean Household Appliance Rental Service Provider
	616,000	Sung Kwang Bend		9,229
		Custom Industrial Pipes
				131,117
		> Taiwan 3.1%
	45,000,000	Yuanta FHC		30,107
		Financial Holding Company in Taiwan
	9,994,000	President Chain Store		25,580
		Taiwan's Number One Convenience Chain Store Operator
	1,322,000	Formosa International Hotels		18,475
		Hotel, Food & Beverage Operation & Hospitality Management Services
	5,844,793	Everlight Electronics		14,859
		LED Packager
	3,655,000	Simplo Technology		14,659
		World's Largest Notebook Battery Pack Supplier
				103,680

Number of Shares			Value (000)
		> Hong Kong 2.4%
	2,700,000	Hong Kong Exchanges and Clearing	$	41,924
		Hong Kong Equity & Derivatives Market Operator
	20,668,600	Lifestyle International		26,878
		Mid to High-end Department Store Operator in Hong Kong & China
	74,150,656	NagaCorp		9,788
		Casino/Entertainment Complex in Cambodia
				78,590
		> Indonesia 0.7%
	75,000,000	Perusahaan Gas Negara		23,051
		Gas Distributor & Pipeline Operator
				23,051
Asia: Total				1,419,038
Europe 34.7%
		> United Kingdom 7.0%
	5,500,000	Serco		38,212
		Facilities Management
	2,185,600	Intertek Group		37,684
		Testing, Inspection & Certification Services
	3,100,000	Capita Group		36,547
		White Collar, Back Office Outsourcing
	2,500,000	Smith & Nephew		18,534
		Medical Equipment & Supplies
	384,000	Chemring		13,727
		Defense Manufacturer of Countermeasures & Energetics
	1,000,000	Rotork		13,639
		Valve Actuators for Oil & Water Pipelines
	212,000	Randgold Resources - ADR		13,604
		Gold Mining in Western Africa
	4,000,000	RPS Group		13,190
		Environmental Consulting & Planning
	4,434,000	Cobham		12,647
		Aerospace Components
	690,000	Tullow Oil		10,675
		Oil & Gas Producer
	2,730,000	N Brown Group		9,664
		Home Shopping Women's Clothes Retailer
	1,000,000	Keller Group		9,115
		Ground Engineering
	864,000	Intermediate Capital		6,909
		European Provider of Mezzanine Capital
				234,147
		> Netherlands 6.0%
	1,871,250	Imtech		36,421
		Engineering & Technical Services
	1,372,989	Koninklijke TenCate (a)		33,254
		Advanced Textiles & Industrial Fabrics
	661,945	Fugro		27,487
		Sub-sea Oilfield Services
	1,385,000	Unit 4 Agresso (b)(a)		22,654
		Business Development Software
	390,900	Vopak (b)		19,553
		World's Largest Operator of Petroleum & Chemical Storage Terminals

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Netherlands—continued
	1,088,187	Arcadis	$	18,126
		Engineering Consultant
	2,051,535	Aalberts Industries		16,142
		Flow Control & Heat Treatment
	244,969	Smit Internationale		14,519
		Harbor & Offshore Towage & Marine Services
	650,000	QIAGEN (b)		12,064
		Life Science Tools & Molecular Diagnostics
				200,220
		> Germany 4.7%
	524,000	Wincor Nixdorf		29,385
		Retail POS Systems & ATM Machines
	700,000	CTS Eventim		28,355
		Event Ticket Sales
	200,000	Vossloh		24,056
		Rail Infrastructure & Diesel Locomotives
	1,010,947	Rhoen-Klinikum		22,354
		Health Care Services
	155,000	Rational		17,880
		Commercial Oven Manufacturer
	595,000	Elringklinger		9,925
		Automobile Components
	744,400	Tognum		9,807
		Diesel Engines for Drive & Power Generation Systems
	700,000	Takkt		7,463
		Mail Order Retailer of Office & Warehouse Durables
	354,500	Deutsche Beteiligungs		6,067
		Private Equity Investment Management
				155,292
		> France 4.6%
	295,000	Neopost		26,528
		Postage Meter Machines
	211,000	Iliad		20,495
		Alternative Internet & Telecoms Provider
	944,000	SES		18,023
		Satellite Broadcasting Services
	441,635	SAFT		17,544
		Niche Battery Manufacturer
	222,118	Pierre & Vacances		15,453
		Vacation Apartment Lets
	155,900	Rubis		11,610
		Tank Storage & Liquefied Petroleum Gas Distributor
	190,000	Eurofins Scientific		11,169
		Food Screening & Testing
	399,598	Carbone Lorraine		10,984
		Advanced Industrial Materials
	393,000	Eutelsat		10,153
		Co-leader in European Fixed Satellite Services
	160,701	Norbert Dentressangle		8,009
		Transport
	725,898	Hi-Media (b)		3,633
		Leading Online Advertiser in Europe
				153,601

Number of Shares			Value (000)
		> Switzerland 2.3%
	20,500	Sika	$	22,756
		Chemicals for Construction & Industrial Applications
	275,000	Kuehne & Nagel		21,588
		Freight Forwarding/Logistics
	167,000	Geberit		20,582
		Plumbing Supplies
	85,000	Burckhardt Compression		11,013
		Gas Compression Pumps
				75,939
		> Sweden 2.2%
	3,944,000	Hexagon		35,681
		Measurement Equipment
	3,235,000	SWECO		16,357
		Engineering Consultants
	4,572,226	Nobia (b)		16,320
		Kitchen Cabinet Manufacturing & Sales
	750,000	East Capital Explorer (b)		6,014
		Sweden-based RUS/CEE Investment Fund
				74,372
		> Finland 2.0%
	1,310,000	Stockmann		27,828
		Department Store & Fashion Retailer in Scandinavia & Russia
	1,756,000	Poyry		24,911
		Engineering Consultants
	2,170,000	Ramirent (b)		13,357
		Largest Equipment Rental Company in Scandinavia & Central Eastern Europe
				66,096
		> Ireland 1.4%
	8,100,000	United Drug		22,501
		Irish Pharmaceutical Wholesaler & Outsourcer
	600,000	Aryzta (b)		19,210
		Baked Goods
	286,000	Paddy Power		6,674
		Irish Betting Services
				48,385
		> Italy 1.2%
	15,569,356	CIR (b)		25,755
		Italian Holding Company
	2,045,000	Credito Emiliano (b)		9,815
		Italian Regional Bank
	900,615	GranitiFiandre		3,243
		Innovative Stoneware
				38,813
		> Poland 0.8%
	975,900	Central European Distribution (b)		25,930
		Vodka Production & Spirits Distribution
				25,930
		> Denmark 0.7%
	297,000	Novozymes		24,140
		Industrial Enzymes
				24,140

See accompanying notes to financial statements.

Columbia Acorn International

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Spain 0.7%
	532,000	Red Electrica de Espana	$	24,070
		Spanish Power Grid
				24,070
		> Greece 0.6%
	3,427,000	Intralot		20,660
		Lottery & Gaming Systems & Services
				20,660
		> Czech Republic 0.5%
	114,000	Komercni Banka		15,817
		Leading Czech Republic Universal Bank
				15,817
Europe: Total				1,157,482
Other Countries 11.7%
		> United States 3.6%
	1,340,000	Atwood Oceanics (b)		33,379
		Offshore Drilling Contractor
	475,000	Alexion Pharmaceuticals (b)		19,532
		Biotech Focused on Orphan Diseases
	275,000	Oceaneering International (b)		12,430
		Provider of Sub-sea Services & Manufactured Products
	180,000	Cephalon (b)		10,197
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	251,000	FMC Technologies (b)		9,433
		Oil & Gas Wellhead Manufacturer
	300,000	Bristow (b)		8,889
		Largest Provider of Helicopter Services to Offshore Oil & Gas Producers
	200,000	World Fuel Services		8,246
		Global Fuel Broker
	460,000	BioMarin (b)		7,181
		Biotech Focused on Orphan Diseases
	150,000	Illumina (b)		5,841
		Leading Tools & Service Provider for Genetic Analysis
	150,000	Ritchie Brothers Auctioneers (c)		3,517
		Heavy Equipment Auctioneer
	324,000	Tesco (b)		2,573
		Developing New Well Drilling Technologies
				121,218
		> Canada 2.4%
	1,710,000	ShawCor		29,594
		Oil & Gas Pipeline Products
	1,117,000	CCL Industries		22,059
		Leading Global Label Manufacturer
	1,897,000	TriStar Oil & Gas (b)		17,924
		Canadian Oil & Gas Producer
	850,000	Ivanhoe Mines (b)		4,713
	744,000	Ivanhoe Mines (b)		4,166
		Copper Mine Project in Mongolia
	2,262,100	Horizon North Logistics (b)		2,042
		Provides Diversified Oil Service Offering in Northern Canada
				80,498

Number of Shares			Value (000)
		> Australia 2.3%
	7,140,000	Sino Gold (b)	$	29,624
		Gold Mining in The People's Republic of China
	536,000	Australian Stock Exchange		15,925
		Australian Equity & Derivatives Market Operator
	624,735	Perpetual Trustees		14,305
		Mutual Fund Management
	2,000,000	Billabong International		14,055
		Action Sports Apparel Brand Manager
	70,000	Cochlear		3,252
		Cochlear Implants for Hearing
				77,161
		> South Africa 2.3%
	1,973,000	Naspers		51,999
		Media in Africa & Other Emerging Markets
	4,600,000	Mr. Price		16,761
		South African Retailer of Apparel, Household & Sporting Goods
	3,049,000	Uranium One (b)		6,999
		Uranium Mines in Kazakhstan, the U.S. & Australia
				75,759
		> Israel 0.9%
	2,890,000	Israel Chemicals		28,448
		Producer of Potash, Phosphates, Bromine & Specialty Chemicals
				28,448
		> Kazakhstan 0.2%
	1,770,000	Halyk Savings Bank of Kazakhstan - GDR (b)		7,369
		Largest Retail Bank & Insurer in Kazakhstan
				7,369
		> New Zealand —%
	868,418	Sky City Entertainment		1,499
		Casino/Entertainment Complex
				1,499
Other Countries: Total				391,952
Latin America 5.4%
		> Brazil 2.8%
	5,500,000	Localiza Rent A Car		33,963
		Car Rental
	4,300,000	Suzano (b)		33,268
		Brazilian Pulp & Paper Producer
	2,000,000	Natura		26,394
		Direct Retailer of Cosmetics
				93,625
		> Mexico 1.7%
	18,000,000	Urbi Desarrollos Urbanos (b)		27,338
		Affordable Housing Builder
	700,000	Grupo Aeroportuario del Sureste - ADR		27,300
		Mexican Airport Operator
				54,638

See accompanying notes to financial statements.

Number of Shares or Principal Amount (000)			Value (000)
		> Chile 0.9%
	862,000	Sociedad Quimica y Minera de Chile - ADR	$	31,196
		Producer of Specialty Fertilizers, Lithium & Iodine
				31,196
Latin America: Total				179,459
Total Equities: 94.4% (Cost: $2,898,869)				3,147,931
Securities Lending Collateral: 0.1%
	1,944,000	Dreyfus Government Cash Management Fund (d) (7 day yield of 0.150%)		1,944
Total Securities Lending Collateral: (Cost: $1,944)				1,944
Short-Term Obligations: 4.9%
		> Repurchase Agreement 4.4%
$	146,027	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.0001%, collateralized by U.S. Government Agency obligations with various maturities to 3/15/16, market value $148,951 (repurchase proceeds $146,027)		146,027
				146,027
		> Commercial Paper 0.5%
	16,800	Toyota Motor Credit 0.26% due 7/06/09		16,800
				16,800
Total Short-Term Obligations: (Amortized Cost: $162,827)				162,827
Total Investments: 99.4% (Cost: $3,063,640)(e)(f)				3,312,702
Obligation to Return Collateral for Securities Loaned: (0.1)%				(1,944	)
Cash and Other Assets Less Liabilities: 0.7%				22,744
Total Net Assets: 100.0%			$	3,333,502

ADR = American Depositary Receipts.

GDR = Global Depositary Receipts.

See accompanying notes to financial statements.

Columbia Acorn International

Statement of Investments (Unaudited), continued

> Notes to Statement of Investments (dollar values in thousands)

Affiliates	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 6/30/09		Value		Dividend
Ain Pharmaciez		643,000		-		-		643,000	$	13,332	$	185
Koninklijke TenCate		1,556,239		78,456		261,706		1,372,989		33,254		725
Unit 4 Aggresso		1,385,000		-		-		1,385,000		22,654		-
Total of Affiliated Transactions		3,584,239		78,456		261,706		3,400,989	$	69,240	$	910

The aggregate cost and value of these companies at June 30, 2009, were $59,544 and $69,240, respectively. Investments in affiliated companies represented 2.1% of total net assets at June 30, 2009.

(b) Non-income producing security.

(c) All or a portion of this security was on loan at June 30, 2009. The total market value of securities on loan at June 30, 2009 was $1,905.

(d) Investment made with cash collateral received from securities lending activity.

(f) On June 30, 2009, the Fund's total investments were denominated in currencies as follows:

Currency	Value		Percentage of Net Assets
Euro	$	712,267		21.4
Japanese Yen		612,747		18.4
U.S. Dollar		450,674		13.5
British Pound		220,543		6.6
Hong Kong Dollar		207,546		6.2
Other currencies less than 5% of total net assets		1,108,925		33.3
	$	3,312,702		99.4

At June 30, 2009, the Fund had entered into the following forward foreign currency exchange contracts:

Forward Foreign Currency Contracts to Buy	Forward Foreign Currency Contracts to Sell	Principal Amount in Foreign Currency			Principal Amount in U.S. Dollar		Settlement Date	Unrealized Appreciation
AUD	USD		6,917		$	5,000	7/15/2009	$	569
AUD	USD		13,288			10,000	8/14/2009		674
CAD	USD		24,233			20,000	7/15/2009		835
CAD	USD		17,589	��		15,000	8/14/2009		125
JPY	USD		1,977,760			20,000	7/15/2009		533
JPY	USD		2,452,150			25,000	9/15/2009		476
					$	95,000		$	3,212
Forward Foreign Currency Contracts to Buy	Forward Foreign Currency Contracts to Sell	Principal Amount in Foreign Currency			Principal Amount in U.S. Dollar		Settlement Date	Unrealized (Depreciation)
AUD	USD		18,581		$	15,000	9/15/2009	$	(110	)
CAD	USD		33,561			30,000	9/15/2009		(1,134	)
JPY	USD		2,384,325			25,000	8/14/2009		(238	)
USD	EUR		33,940			45,000	7/15/2009		(2,614	)
USD	EUR		36,714			50,000	8/14/2009		(1,503	)
USD	EUR		49,938			70,000	9/15/2009		(47	)
					$	235,000		$	(5,646	)

The counterparty for all forward foreign currency exchange contracts is State Street Bank and Trust Company.

AUD = Australian Dollar

CAD = Canadian Dollar

EUR = Euro

JPY = Japanese Yen

USD = United States Dollar

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)		Total
Equities
Total Asia	$	55,121	$	1,363,917		$	-	$	1,419,038
Total Europe		39,534		1,117,948			-		1,157,482
Total Other Countries		208,715		183,237			-		391,952
Total Latin America		179,459		-			-		179,459
Total Equities		482,829		2,665,102			-		3,147,931
Securities Lending Collateral		1,944		-			-		1,944
Short-Term Obligations		-		162,827			-		162,827
Total Investments	$	484,773	$	2,827,929		$	-	$	3,312,702
Net Forward Foreign Currency Exchange Contracts	$	-	$	(2,434	)	$	-	$	(2,434	)
Total	$	484,773	$	2,825,495		$	-	$	3,310,268

The Fund's assets assigned to the Level 2 input category include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation.

Investments in Secruities	Balance as of December 31, 2008		Accrued Discounts/ Premiums		Realized Gain/(Loss)		Change in Unrealized Appreciation (Depreciation)		Net Purchases		Net Sales		Net transfers into Level 3		Net transfers out of Level 3			Balance as of June 30, 2009		Change in Unrealized Appreciation (Depreciation) from Investments held at June 30, 2009
Asia
Hong Kong	$	312	$	-	$	-	$	-	$	-	$	-	$	-	$	(312	)	$	-	$	-
Total	$	312	$	-	$	-	$	-	$	-	$	-	$	-	$	(312	)	$	-	$	-

See accompanying notes to financial statements.

Columbia Acorn International

Portfolio Diversification

At June 30, 2009, the Fund's portfolio investments as a percentage of net assets were diversified as follows:

	Value (000)		Percentage of Net Assets
> Industrial Goods & Services
Industrial Materials & Specialty Chemicals	$	253,329		7.6
Other Industrial Services		251,676		7.5
Machinery		197,273		5.9
Outsourcing Services		124,920		3.7
Electrical Components		63,501		1.9
Conglomerates		34,020		1.0
Construction		33,214		1.0
Medical Equipment & Devices		14,187		0.4
Industrial Distribution		7,290		0.2
Waste Management		5,130		0.2
		984,540		29.4
> Consumer Goods & Services
Retail		118,853		3.6
Other Consumer Services		89,533		2.7
Nondurables		84,549		2.5
Food & Beverage		84,026		2.5
Apparel		61,345		1.8
Casinos & Gaming		58,282		1.7
Travel		49,416		1.5
Other Entertainment		46,830		1.4
Consumer Goods Distribution		25,930		0.8
Educational Services		25,731		0.8
Furniture & Textiles		16,320		0.5
Consumer Electronics		10,704		0.3
		671,519		20.1
> Information
Financial Processors		76,123		2.3
Computer Hardware & Related Equipment		59,179		1.8
Internet Related		54,348		1.6
TV Broadcasting		51,999		1.6
Instrumentation		46,737		1.4
Publishing		40,026		1.2
Satellite Broadcasting & Services		28,176		0.8
CATV		23,882		0.7
Business Software		22,654		0.7
Semiconductors & Related Equipment		14,859		0.4
Business Information & Marketing Services		13,190		0.4
Advertising		9,743		0.3
		440,916		13.2
> Other Industries
Real Estate		168,885		5.1
Transportation		115,507		3.5
Conglomerates		25,755		0.8
Regulated Utilities		24,070		0.7
		334,217		10.1

	Value (000)			Percentage of Net Assets
> Energy & Minerals
Oil Services	$	125,827			3.8
Mining		59,106			1.8
Oil Refining, Marketing & Distribution		54,214			1.6
Agricultural Commodities		33,268			1.0
Oil & Gas Producers		28,599			0.9
		301,014			9.1
> Finance
Brokerage & Money Management		92,786			2.8
Banks		88,038			2.6
Finance Companies		40,928			1.2
Savings & Loans		22,075			0.7
		243,827			7.3
> Health Care
Medical Equipment & Devices		94,018			2.8
Pharmaceuticals		36,281			1.1
Health Care Services		22,354			0.7
Medical Supplies		12,064			0.4
Biotechnology & Drug Delivery		7,181			0.2
		171,898			5.2
Total Equities:		3,147,931			94.4
Securities Lending Collateral:		1,944			0.1
Short-Term Obligations:		162,827			4.9
Total Investments:		3,312,702			99.4
Obligation to Return Collateral for Securities Loaned:		(1,944	)		(0.1	)
Cash and Other Assets Less Liabilities:		22,744			0.7
Net Assets:	$	3,333,502			100.0

See accompanying notes to financial statements.

Columbia Acorn USA

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Information
Bally Technologies		410,000		570,000
Blue Coat Systems		0		83,724
Cogent Communications		240,000		840,000
CommScope		0		335,000
Entegris		0		750,000
Informatica		943,000		1,093,000
ManTech International		0		50,000
Monolithic Power Systems		100,000		340,000
Netgear		0		135,000
NetSuite		150,000		240,000
Pericom Semiconductor		225,000		480,000
SBA Communications		0		130,000
Switch & Data Facilities		870,500		947,000
tw telecom		1,736,000		2,061,000
Consumer Goods & Services
American Apparel		0		334,296
Avis Budget Group		0		907,750
Bebe Stores		0		262,000
Cavco Industries		306,672		337,900
Charlotte Russe		0		270,878
Charming Shoppes		0		609,879
Chico's FAS		607,000		824,000
Children's Place Retail Stores		60,000		90,000
Gaylord Entertainment		411,000		528,969
Hertz		0		750,000
Interface		0		349,300
J Crew Group		154,000		246,000
Knoll		580,000		780,000
Lifetime Fitness		0		110,000
Lululemon Athletica		0		165,000
New York & Company		0		333,700
Saks		0		459,000
Universal Technical Institute		0		165,000
Industrial Goods & Services
Albany International		0		150,000
Drew Industries		238,889		255,000
GrafTech International		0		200,000
HEICO		0		100,000
Interline Brands		225,000		375,000
M/I Homes		140,000		240,000
Oshkosh		0		200,000
Ritchie Brothers Auctioneers		0		110,000

	Number of Shares
	03/31/09		06/30/09
Finance
CIT Group		0		700,000
Delphi Financial Group		0		110,000
GATX		205,000		365,000
H&E Equipment Services		514,396		625,000
McGrath Rentcorp		220,000		345,000
MF Global		0		750,000
Wilmington Trust		0		140,000
Health Care
American Medical Systems		33,398		100,000
Auxilium Pharmaceuticals		125,000		165,000
Cepheid		345,900		450,000
Luminex		260,100		350,000
Medarex		320,000		445,000
NPS Pharmaceuticals		0		290,935
Energy & Minerals
Atwood Oceanics		555,000		720,000
Carrizo Oil & Gas		315,000		485,000
Oceaneering International		75,111		130,111
Other Industries
Corporate Office Properties		113,100		170,000
DCT Industrial Trust		0		470,000
Kite Realty Group		150,000		1,450,000
Macerich Company		0		266,953
SL Green Realty		110,000		405,000

See accompanying notes to financial statements.

Columbia Acorn USA

Major Portfolio Changes in the Second Quarter (Unaudited), continued

	Number of Shares
	03/31/09		06/30/09
Sales
Information
American Tower		376,000		100,000
FLIR Systems		700,000		460,740
Tellabs		528,000		0
Consumer Goods & Services
Abercrombie & Fitch		357,000		281,000
ITT Educational Services		232,000		202,000
True Religion Apparel		600,213		381,313
Industrial Goods & Services
Administaff		175,000		85,000
ESCO Technologies		650,300		625,300
Pentair		533,600		500,000
Simpson Manufacturing		195,000		0
Waste Connections		280,875		130,000
Finance
HCC Insurance Holdings		714,500		0
People's United		407,040		77,040
Health Care
Cephalon		145,000		125,000
Lincare Holdings		126,800		0
Meridian Biosciences		105,000		0
Savient Pharmaceuticals		400,000		280,000

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 98.1%
Information 32.5%
		> Business Software 7.7%
	1,093,000	Informatica (a)	$	18,789
		Enterprise Data Integration Software
	695,100	Micros Systems (a)		17,600
		Information Systems for Restaurants & Hotels
	2,100,000	Novell (a)		9,513
		Directory, Operating System & Identity Management Software
	305,000	ANSYS (a)		9,504
		Simulation Software for Engineers & Designers
	288,000	Concur Technologies (a)		8,951
		Web Enabled Cost & Expense Management Software
	525,000	Blackbaud		8,164
		Software & Services for Non-profits
	100,000	Quality Systems (b)		5,696
		IT Systems for Medical Groups & Ambulatory Care Centers
	240,000	NetSuite (a)(b)		2,834
		End to End IT Systems Solution Delivered Over the Web
	100,000	Avid Technology (a)		1,341
		Digital Nonlinear Editing Software & Systems
	180,000	Art Technology Group (a)		684
		Software & Tools to Optimize Websites for E-Commerce
	114,300	Actuate (a)		546
		Information Delivery Software & Solutions
				83,622
		> Semiconductors & Related Equipment 4.0%
	760,000	Microsemi (a)		10,488
		Analog/Mixed-signal Semiconductors
	1,179,750	ON Semiconductor (a)		8,093
		Mixed-signal & Power Management Semiconductors
	340,000	Monolithic Power Systems (a)		7,619
		High Performance Analog & Mixed Signal Integrated Circuits (ICs)
	1,168,000	Integrated Device Technology (a)		7,055
		Communications Semiconductors
	189,296	Supertex (a)		4,753
		Analog/Mixed-signal Semiconductors
	480,000	Pericom Semiconductor (a)		4,042
		Interface Integrated Circuits (ICs) & Frequency Control Products
	750,000	Entegris (a)		2,040
		Semiconductor Materials Management Products
				44,090
		> Instrumentation 3.4%
	180,000	Mettler Toledo (a)		13,887
		Laboratory Equipment
	460,740	FLIR Systems (a)		10,394
		Infrared Cameras
	775,000	IPG Photonics (a)		8,502
		Fiber Lasers

Number of Shares			Value (000)
	168,000	Trimble Navigation (a)	$	3,298
		GPS-based Instruments
	36,000	FARO Technologies (a)		559
		Precision Measurement Equipment
				36,640
		> Mobile Communications 3.3%
	1,250,000	Crown Castle International (a)		30,025
		Communications Towers
	130,000	SBA Communications (a)		3,190
		Communications Towers
	100,000	American Tower (a)		3,153
		Communications Towers in USA & Latin America
	88,000	Globalstar (a)		93
		Satellite Mobile Voice & Data Carrier
				36,461
		> Computer Hardware & Related Equipment 3.0%
	505,000	II-VI (a)		11,196
		Laser Optics & Specialty Materials
	295,600	Amphenol		9,353
		Electronic Connectors
	280,000	Nice Systems - ADR (Israel) (a)		6,460
		Audio & Video Recording Solutions
	184,000	Zebra Technologies (a)		4,353
		Bar Code Printers
	135,000	Netgear (a)		1,945
		Networking Products for Small Business & Home
				33,307
		> Telephone and Data Services 2.8%
	2,061,000	tw telecom (a)		21,166
		Fiber Optic Telephone/Data Services
	840,000	Cogent Communications (a)		6,846
		Internet Data Pipelines
	800,000	PAETEC Holding (a)		2,160
		Telephone/Data Services for Business
				30,172
		> Telecommunications Equipment 1.9%
	525,000	Polycom (a)		10,642
		Video Conferencing Equipment
	335,000	CommScope (a)		8,797
		Wireless Infrastructure Equipment & Telecom Cable
	83,724	Blue Coat Systems (a)		1,385
		WAN Acceleration & Network Security
				20,824
		> Gaming Equipment & Services 1.7%
	570,000	Bally Technologies (a)		17,054
		Slot Machines & Software
	100,000	Scientific Games (a)		1,577
		Lottery Services Provider
				18,631
		> Financial Processors 1.7%
	483,280	Global Payments		18,104
		Credit Card Processor
				18,104

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Internet Related 1.4%
	947,000	Switch & Data Facilities (a)	$	11,108
		Network Neutral Data Centers
	40,000	Equinix (a)		2,910
		Network Neutral Data Centers
	381,740	TheStreet.com		798
		Financial Information Websites
				14,816
		> Computer Services 1.2%
	275,000	SRA International (a)		4,829
		Government IT Services
	1,005,500	Hackett Group (a)		2,343
		IT Integration & Best Practice Research
	50,000	ManTech International (a)		2,152
		Government IT Services
	786,000	RCM Technologies (a)(c)		1,745
		Technology & Engineering Services
	235,000	iGate		1,555
		IT & Business Process Outsourcing Services
				12,624
		> Contract Manufacturing 0.2%
	115,000	Plexus (a)		2,353
		Electronic Manufacturing Services
				2,353
		> CATV 0.1%
	305,785	Mediacom Communications (a)		1,563
		CATV Franchises
				1,563
		> Radio 0.1%
	511,100	Salem Communications (a)		491
		Radio Stations for Religious Programming
	705,500	Spanish Broadcasting System (a)		127
		Spanish Language Radio Stations
	18,750	Saga Communications (a)		96
		Radio Stations in Small & Mid-sized Cities
				714
		> TV Broadcasting —%
	975,000	Entravision Communications (a)		468
		Spanish Language TV & Radio Stations
				468
Information: Total				354,389
Consumer Goods & Services 15.0%
		> Retail 5.0%
	402,000	Urban Outfitters (a)		8,390
		Apparel & Home Specialty Retailer
	824,000	Chico's FAS (a)		8,017
		Women's Specialty Retailer
	281,000	Abercrombie & Fitch		7,135
		Teen Apparel Retailer
	246,000	J Crew Group (a)(b)		6,647
		Multi-channel Branded Retailer
	497,714	Hot Topic (a)		3,638
		Music Inspired Retailer of Apparel, Accessories & Gifts
	270,878	Charlotte Russe (a)		3,489
		Value Fashion Retailer

Number of Shares			Value (000)
	480,000	Talbots (b)	$	2,592
		Women's Specialty Retailer
	90,000	Children's Place Retail Stores (a)		2,379
		Specialty Children's Retailer
	609,879	Charming Shoppes (a)		2,269
		Women's Specialty Plus Size Apparel Retailer
	165,000	Lululemon Athletica (a)(b)		2,150
		Premium Active Apparel Retailer
	459,000	Saks (a)		2,033
		Luxury Department Store Retailer
	262,000	Bebe Stores		1,802
		Women's Contemporary Specialty Apparel Retailer
	94,000	Hibbett Sports (a)		1,692
		Sporting Goods Retailer
	334,296	American Apparel (a)		1,217
		Vertically Integrated Apparel Retailer
	333,700	New York & Company (a)		1,031
		Women's Specialty Retailer
				54,481
		> Educational Services 2.1%
	202,000	ITT Educational Services (a)		20,333
		Post-secondary Degree Services
	165,000	Universal Technical Institute (a)		2,464
		Vocational Training
				22,797
		> Travel 2.0%
	528,969	Gaylord Entertainment (a)(b)		6,723
		Convention Hotels
	750,000	Hertz (a)		5,992
		Largest U.S. Rental Car Operator
	907,750	Avis Budget Group (a)		5,129
		Second Largest Car Rental Company
	150,000	Vail Resorts (a)		4,023
		Ski Resort Operator & Developer
				21,867
		> Apparel 1.3%
	381,313	True Religion Apparel (a)		8,503
		Premium Denim
	222,200	Coach		5,973
		Designer & Retailer of Branded Leather Accessories
				14,476
		> Furniture & Textiles 1.1%
	780,000	Knoll		5,912
		Office Furniture
	285,000	Herman Miller		4,372
		Office Furniture
	349,300	Interface		2,166
		Modular & Broadloom Carpet
				12,450
		> Other Durable Goods 0.9%
	337,900	Cavco Industries (a)(c)		8,559
		High End Manufactured Homes
	2,078,300	Champion Enterprises (a)		665
		Manufactured Homes
				9,224

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Consumer Goods Distribution 0.8%
	523,500	Pool	$	8,669
		Distributor of Swimming Pool Supplies & Equipment
				8,669
		> Nondurables 0.5%
	298,000	Jarden (a)		5,588
		Branded Household Products
				5,588
		> Leisure Products 0.4%
	180,000	Thor Industries		3,307
		RV & Bus Manufacturer
	150,000	Winnebago Industries		1,114
		Motor Home Maker
				4,421
		> Casinos & Gaming 0.4%
	455,000	Pinnacle Entertainment (a)		4,227
		Regional Casino Operator
				4,227
		> Food & Beverage 0.3%
	90,000	Hansen Natural (a)		2,774
		Alternative Beverages
				2,774
		> Other Consumer Services 0.2%
	110,000	Lifetime Fitness (a)		2,201
		Sport & Fitness Club Operator
				2,201
Consumer Goods & Services: Total				163,175
Industrial Goods & Services 14.7%
		> Machinery 10.3%
	625,300	ESCO Technologies (a)		28,013
		Automatic Electric Meter Readers
	627,500	Ametek		21,699
		Aerospace/Industrial Instruments
	445,000	Donaldson		15,415
		Industrial Air Filtration
	373,600	Nordson		14,443
		Dispensing Systems for Adhesives & Coatings
	500,000	Pentair		12,810
		Pumps & Water Treatment
	195,000	MOOG (a)		5,033
		Motion Control Products for Aerospace, Defense & Industrial Markets
	155,000	Mine Safety Appliances		3,736
		Safety Equipment
	100,000	HEICO		2,926
		FAA Approved Aircraft Replacement Parts
	200,000	Oshkosh		2,908
		Specialty Truck Manufacturer
	71,800	Toro (b)		2,147
		Turf Maintenance Equipment
	60,000	Clarcor		1,751
		Mobile & Industrial Filters
	50,000	Kaydon		1,628
		Specialized Friction & Motion Control Products
				112,509

Number of Shares			Value (000)
		> Industrial Materials & Specialty Chemicals 1.2%
	255,000	Drew Industries (a)	$	3,104
		RV & Manufactured Home Components
	163,000	Nalco Holding Company		2,745
		Provider of Water Treatment & Process Chemicals & Services
	50,000	Greif		2,211
		Industrial Packaging
	65,000	Koppers Holdings		1,714
		Integrated Provider of Carbon Compounds
	150,000	Albany International		1,707
		Paper Machine Clothing & Advanced Textiles
	60,000	Albemarle		1,534
		Refinery Catalysts & Other Specialty Chemicals
				13,015
		> Outsourcing Services 0.9%
	350,000	Quanta Services (a)		8,095
		Electrical & Telecom Construction Services
	85,000	Administaff		1,978
		Professional Employer Organization
				10,073
		> Other Industrial Services 0.5%
	396,000	American Reprographics (a)		3,295
		Document Management & Logistics
	265,000	TrueBlue (a)		2,226
		Temporary Manual Labor
				5,521
		> Industrial Distribution 0.5%
	375,000	Interline Brands (a)		5,130
		Industrial Distribution
				5,130
		> Construction 0.4%
	110,000	Ritchie Brothers Auctioneers (b)		2,579
		Heavy Equipment Auctioneer
	240,000	M/I Homes (a)		2,350
		Columbus-based Home Builder
				4,929
		> Electrical Components 0.4%
	145,000	Acuity Brands		4,067
		Commercial Lighting Fixtures
				4,067
		> Waste Management 0.3%
	130,000	Waste Connections (a)		3,368
		Solid Waste Management
				3,368
		> Steel 0.2%
	200,000	GrafTech International (a)		2,262
		Industrial Graphite Materials Producer
				2,262
Industrial Goods & Services: Total				160,874

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
Finance 13.8%
		> Finance Companies 5.2%
	1,136,500	AmeriCredit (a)(b)	$	15,400
		Auto Lending
	365,000	GATX		9,388
		Rail Car Lessor
	275,000	Aaron's		8,200
		Rent to Own
	407,900	World Acceptance (a)		8,121
		Personal Loans
	345,000	McGrath Rentcorp		6,576
		Temporary Space & IT Rentals
	625,000	H&E Equipment Services (a)		5,844
		Heavy Equipment Leasing
	700,000	CIT Group		1,505
		Middle Market Lender, Equipment Leasing & Vendor Finance/Factoring
	230,000	CAI International (a)		1,173
		International Container Leasing
	99,200	Marlin Business Services (a)		555
		Small Equipment Leasing
				56,762
		> Banks 4.7%
	935,182	Valley National Bancorp		10,942
		New Jersey/New York Bank
	659,800	TCF Financial		8,821
		Great Lakes Bank
	414,088	Lakeland Financial		7,868
		Indiana Bank
	508,000	Pacific Continental		6,162
		Pacific N.W. Bank
	468,025	MB Financial		4,769
		Chicago Bank
	103,000	SVB Financial Group (a)		2,804
		Bank to Venture Capitalists
	213,600	Associated Banc-Corp		2,670
		Midwest Bank
	140,000	Wilmington Trust		1,912
		Delaware Trust Bank
	46,000	BOK Financial		1,733
		Tulsa-based Southwest Bank
	851,247	Guaranty Bancorp (a)		1,626
		Colorado Bank
	90,000	TriCo Bancshares		1,395
		California Central Valley Bank
	166,527	Green Bankshares (b)		746
		Tennessee Bank
				51,448
		> Brokerage & Money Management 1.6%
	280,000	Eaton Vance		7,490
		Specialty Mutual Funds
	750,000	MF Global (a)		4,448
		Futures Broker
	155,000	Investment Technology Group (a)		3,160
		Electronic Trading
	150,000	SEI Investments		2,706
		Mutual Fund Administration & Investment Management
				17,804

Number of Shares			Value (000)
		> Savings & Loans 1.4%
	600,000	ViewPoint Financial	$	9,138
		Texas Thrift
	238,090	Berkshire Hills Bancorp		4,947
		Northeast Thrift
	77,040	People's United		1,159
		Connecticut Savings & Loan
	42,231	K-Fed Bancorp		388
		Los Angeles Savings & Loan
				15,632
		> Insurance 0.9%
	120,000	Tower Group		2,974
		Commercial & Personal Lines Insurance
	75,000	Endurance Specialty Holdings		2,197
		Commercial Lines Insurance/Reinsurance
	110,000	Delphi Financial Group		2,137
		Workers Compensation & Group Employee Benefit Products & Services
	7,000	Markel (a)		1,972
		Specialty Insurance
				9,280
Finance: Total				150,926
Health Care 10.3%
		> Biotechnology & Drug Delivery 3.6%
	180,000	Myriad Genetics (a)		6,416
		Genetic Diagnostics
	165,000	Auxilium Pharmaceuticals (a)		5,178
		Biotech Focused on Niche Disease Areas
	474,700	Seattle Genetics (a)		4,614
		Antibody-based Therapies for Cancer
	270,000	BioMarin (a)		4,215
		Biotech Focused on Orphan Diseases
	280,000	Savient Pharmaceuticals (a)		3,881
		Biotech Company Focused on Niche Disease Areas
	445,000	Medarex (a)		3,716
		Humanized Antibodies
	43,000	United Therapeutics (a)		3,583
		Biotech Focused on Rare Diseases
	518,295	Nektar Therapeutics (a)		3,358
		Drug Delivery Technologies
	161,286	InterMune (a)		2,451
		Drugs for Pulmonary Fibrosis & Hepatitis C
	290,935	NPS Pharmaceuticals (a)		1,356
		Orphan Drugs & Healthy Royalties
	500,000	IsoRay (a)		125
	100,000	IsoRay - Warrants (a)(d)		5
		Radiology Cancer Company
	19,425	Poniard (a)		116
		Cancer Biotech
	18,181	Metabolex, Series A-1 (a)(d)		19
		Diabetes Drug Development
	738,060	Medicure - Warrants (a)(d)
		Cardiovascular Biotech Company		7
	37,500	Locus Pharmaceuticals, Series A-1, Pfd. (a)(d)		3
	19,329	Locus Pharmaceuticals, Series B-1, Pfd. (a)(d)		2
		High Throughput Rational Drug Design
				39,045

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Medical Supplies 2.4%
	158,300	Techne	$	10,101
		Cytokines, Antibodies & Other Reagents for Life Science
	350,000	Luminex (a)		6,489
		Life Science Tools & Molecular Diagnostics
	450,000	Cepheid (a)		4,239
		Molecular Diagnostics
	180,000	Immucor (a)		2,477
		Automated Blood Typing Reagents
	53,000	Idexx Laboratories (a)		2,449
		Diagnostic Equipment & Services for Veterinarians
				25,755
		> Health Care Services 1.9%
	606,300	PSS World Medical (a)		11,223
		Distributor of Medical Supplies
	242,000	Psychiatric Solutions (a)		5,503
		Behavioral Health Services
	67,000	Charles River Laboratories (a)		2,261
		Pharmaceutical Research
	283,000	eResearch Technology (a)		1,757
		Clinical Research Services
				20,744
		> Medical Equipment & Devices 1.8%
	235,000	Alexion Pharmaceuticals (a)		9,663
		Biotech Focused on Orphan Diseases
	169,000	Illumina (a)		6,581
		Leading Tools & Service Provider for Genetic Analysis
	100,000	American Medical Systems (a)		1,580
		Medical Devices to Treat Urological Conditions
	50,000	Kinetic Concepts (a)		1,363
		Wound Healing & Tissue Repair Products
				19,187
		> Pharmaceuticals 0.6%
	125,000	Cephalon (a)		7,081
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	13,603	Myriad Pharmaceuticals (a)		63
		Genetic Diagnostics
				7,144
Health Care: Total				111,875
Energy & Minerals 7.8%
		> Oil Services 4.5%
	598,400	FMC Technologies (a)		22,488
		Oil & Gas Wellhead Manufacturer
	720,000	Atwood Oceanics (a)		17,935
		Offshore Drilling Contractor
	130,111	Oceaneering International (a)		5,881
		Provider of Sub-sea Services & Manufactured Products
	115,375	Exterran Holdings (a)		1,850
		Natural Gas Compressor Rental & Fabrication
	106,000	Tesco (a)		842
		Developing New Well Drilling Technologies
				48,996

Number of Shares			Value (000)
		> Oil & Gas Producers 2.9%
	276,800	Southwestern Energy (a)	$	10,754
		Oil & Gas Producer
	925,000	Quicksilver Resources (a)		8,593
		Natural Gas & Coal Seam Gas Producer
	485,000	Carrizo Oil & Gas (a)		8,318
		Oil & Gas Producer
	111,200	Equitable Resources		3,882
		Natural Gas Producer & Utility
				31,547
		> Other Resources 0.4%
	218,000	Layne Christensen (a)		4,458
		Oil & Gas Production/Engineering & Construction/Contract Drilling
				4,458
Energy & Minerals: Total				85,001
Other Industries 4.0%
		> Real Estate 3.1%
	405,000	SL Green Realty		9,291
		Manhattan Office Buildings
	170,000	Corporate Office Properties		4,986
		Office Buildings
	266,953	Macerich Company (b)		4,701
		Regional Shopping Malls
	1,450,000	Kite Realty Group		4,234
		Community Shopping Centers
	100,000	Digital Realty Trust		3,585
		Technology-focused Office Buildings
	90,000	American Campus Communities		1,996
		Student Housing
	470,000	DCT Industrial Trust		1,917
		Industrial Properties
	196,000	Extra Space Storage		1,637
		Self Storage Facilities
	120,000	BioMed Realty Trust		1,228
		Life Science-focused Office Buildings
				33,575
		> Transportation 0.9%
	524,720	Heartland Express		7,724
		Regional Trucker
	180,000	Rush Enterprises, Class A (a)		2,097
		Truck Sales & Service
				9,821
Other Industries: Total				43,396
Total Equities: 98.1% (Cost: $1,114,810)				1,069,636
Securities Lending Collateral: 2.3%
	24,650,050	Dreyfus Government Cash Management Fund (e) (7 day yield of 0.150%)		24,650
Total Securities Lending Collateral: (Cost: $24,650)				24,650

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), continued

Principal Amount (000)			Value (000)
Short-Term Obligation: 2.0%
		> Repurchase Agreement 2.0%
$	21,703	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 07/01/09 at 0.0001%, collateralized by a U.S. Government Agency obligation, maturing 3/15/16, market value $22,142 (repurchase proceeds $21,703)	$	21,703
Total Short-Term Obligation: (Cost: $21,703)				21,703
Total Investments: 102.4% (Cost: $1,161,163)(f)				1,115,989
Obligation to Return Collateral for Securities Loaned: (2.3)%				(24,650	)
Cash and Other Assets Less Liabilities: (0.1)%				(1,553	)
Total Net Assets: 100%			$	1,089,786

ADR = American Depositary Receipts.

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

(a) Non-income producing security.

(b) All or a portion of this security was on loan at June 30, 2009. The total market value of securities on loan at June 30, 2009 was $23,954.

(c) An affiliated person of the Fund may include any company in which the Fund owns five percent or more of its outstanding voting shares.

Transactions in these affiliated companies during the six months ended June 30, 2009, are as follows:

Affiliate	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 6/30/09		Value		Dividend
RCM Technologies		786,000		-		-		786,000	$	1,745	$	-
Cavco Industries		287,900		50,000		-		337,900		8,559		-
Total Affiliated Transactions		1,073,900		50,000		-		1,123,900	$	10,304	$	-

(d) Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued at their fair value determined in good faith under consistently applied procedures established by the board of trustees. At June 30, 2009, these securities amounted to $36, which represented less than 0.01% of total net assets.

Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Metabolex, Series A	2/11/00		18,181	$	2,000	$	19
Medicure - Warrants	12/22/06		738,060		-		7
Locus Pharmaceuticals, Series A-1, Pfd.	9/05/01		37,500		1,500		3
IsoRay - Warrants	3/21/07		100,000		-		5
Locus Pharmaceuticals, Series B-1, Pfd.	2/08/07		19,329		56		2
				$	3,556	$	36

(e) Investment made with cash collateral received from securities lending activity.

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Equities
Total Information	$	354,389	$	-	$	-	$	354,389
Total Consumer Goods & Services		163,175		-		-		163,175
Total Industrial Goods & Services		160,874		-		-		160,874
Total Finance		150,926		-		-		150,926
Total Health Care		111,839		12		24		111,875
Total Energy & Minerals		85,001		-		-		85,001
Total Other Industries		43,396		-		-		43,396
Total Equities		1,069,600		12		24		1,069,636
Securities Lending Collateral		24,650		-		-		24,650
Short-Term Obligation		-		21,703		-		21,703
Total Investments		1,094,250		21,715		24		1,115,989
Total	$	1,094,250	$	21,715	$	24	$	1,115,989

See accompanying notes to financial statements.

Columbia Acorn USA

Statement of Investments (Unaudited), continued

> Notes to Statement of Investments (dollar values in thousands)

Investments in Secruities	Balance as of December 31, 2008		Accrued Discounts/ Premiums		Realized Gain/(Loss)		Change in Unrealized Appreciation (Depreciation)			Net Purchases		Net Sales		Net transfers into Level 3		Net transfers out of Level 3		Balance as of June 30, 2009		Change in Unrealized Appreciation (Depreciation) from Investments held at June 30, 2009
Health Care
Biotechnology & Drug Delivery	$	41	$	-	$	-	$	(17	)	$	-	$	-	$	-	$	-	$	24	$	(17	)
Total	$	41	$	-	$	-	$	(17	)	$	-	$	-	$	-	$	-	$	24	$	(17	)

See accompanying notes to financial statements.

Columbia Acorn International Select

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Asia
> Japan
Aeon Mall		182,000		318,000
Benesse		144,300		166,300
Nintendo		22,500		31,500
Rohto Pharmaceutical		502,200		568,300
Suruga Bank		279,000		307,000
> South Korea
MegaStudy		0		42,480
NHN		29,000		71,100
> Singapore
Ascendas REIT		0		2,291,500
OLAM International		0		5,250,000
Singapore Exchange		0		702,000
> Hong Kong
Hong Kong Exchanges and Clearing		370,000		434700
Lifestyle International		0		666,300
NagaCorp		7,798,800		9,776,566
> China
Shandong Weigao		0		1,516,000
> Taiwan
Ishares MSCI Taiwan Index Fund		0		244,800
Europe
> United Kingdom
Capita Group		950,000		1,060,000
Cobham		1,035,000		2,000,000
Intertek Group		561,600		641,600
Serco		2,000,000		2,300,000
> France
Eutelsat		0		117,000
Neopost		29,500		83,500
> Netherlands
Fugro		0		120,162
Imtech		0		169,000
Other Countries
> Canada
CCL Industries		0		134,000
Pacific Rubiales Energy		473,867		1,308,000
Potash Corp. of Saskatchewan		95,400		117,400
> United States
Alexion Pharmaceuticals		107,600		220,000
Atwood Oceanics		0		115,000
> South Africa
Naspers		421,000		630,000

	Number of Shares
	03/31/09		06/30/09
> Israel
Israel Chemicals		620,000		1,203,000
> Australia
Sino Gold		1,205,000		1,275,000
Latin America
> Chile
Sociedad Quimica y Minera de Chile - ADR		90,000		182,000

See accompanying notes to financial statements.

Columbia Acorn International Select

Major Portfolio Changes in the Second Quarter (Unaudited), continued

	Number of Shares
	03/31/09		06/30/09
Sales
Asia
> Japan
Jupiter Telecommunications		15,600		9,000
Ryohin Keikaku		70,000		0
> South Korea
Woongjin Coway		256,000		116,000
> Singapore
ComfortDelGro		1,680,000		0
Europe
> United Kingdom
RPS Group		1,100,000		973,000
Smith & Nephew		896,000		0
> France
SES		471,000		210,000
> Germany
Rhoen-Klinikum		400,000		197,200
> Netherlands
QIAGEN		150,000		0
> Sweden
Hexagon		893,000		669,000
> Ireland
Aryzta		96,000		0
United Drug		2,200,000		2,100,000
> Switzerland
Kuehne & Nagel		39,700		35,700
Swatch Group		18,200		0
Synthes		42,000		0
> Greece
Intralot		654,000		0
Other Countries
> Canada
Pacific Rubiales Energy		276133		0
> United States
BioMarin		110,000		0
Bristow		55000		0
Cephalon		155,000		85,000
Diamond Offshore		78,000		47,000
Oceaneering International		98,000		63,000

See accompanying notes to financial statements.

Columbia Acorn International Select

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 91.7%
Asia 33.7%
		> Japan 19.5%
	1,277,000	Kansai Paint	$	9,143
		Paint Producer in Japan, India, China & Southeast Asia
	31,500	Nintendo		8,669
		Entertainment Software & Hardware
	2,740	Seven Bank		7,165
		ATM Processing Services
	9,000	Jupiter Telecommunications		6,823
		Largest Cable Service Provider in Japan
	166,300	Benesse		6,646
		Education Service Provider
	568,300	Rohto Pharmaceutical		6,412
		Health & Beauty Products
	318,000	Aeon Mall		6,017
		Suburban Shopping Mall Developer, Owner & Operator
	900	Orix JREIT		4,120
		Diversified REIT
	435,000	Kamigumi		3,662
		Port Cargo Handling & Logistics
	307,000	Suruga Bank		2,926
		Regional Bank
	330	Nippon Building Fund		2,824
		Office REIT
	67,000	Ain Pharmaciez		1,389
		Dispensing Pharmacy/Drugstore Operator
				65,796
		> South Korea 6.0%
	71,100	NHN (a)		9,824
		South Korea's Largest Online Search Engine
	42,480	MegaStudy		7,646
		Online Education Service Provider
	116,000	Woongjin Coway		2,815
		South Korean Household Appliance Rental Service Provider
				20,285
		> Singapore 4.4%
	5,250,000	OLAM International		8,778
		Agriculture Supply Chain Manager
	702,000	Singapore Exchange		3,430
		Singapore Equity & Derivatives Market Operator
	2,291,500	Ascendas REIT		2,508
		Singapore Industrial Property Landlord
				14,716
		> Hong Kong 2.6%
	434,700	Hong Kong Exchanges and Clearing		6,750
		Hong Kong Equity & Derivatives Market Operator
��	9,776,566	NagaCorp		1,291
		Casino/Entertainment Complex in Cambodia
	666,300	Lifestyle International		866
		Mid to High-end Department Store Operator in Hong Kong & China
				8,907

Number of Shares			Value (000)
		> China 1.2%
	1,516,000	Shandong Weigao	$	3,885
		Vertically Integrated Hospital Consumable Manufacturer
				3,885
Asia: Total				113,589
Europe 31.7%
		> United Kingdom 14.4%
	2,300,000	Serco		15,979
		Facilities Management
	1,060,000	Capita Group		12,497
		White Collar, Back Office Outsourcing
	641,600	Intertek Group		11,063
		Testing, Inspection & Certification Services
	2,000,000	Cobham		5,705
		Aerospace Components
	973,000	RPS Group		3,208
		Environmental Consulting & Planning
				48,452
		> France 4.3%
	83,500	Neopost		7,509
		Postage Meter Machines
	210,000	SES		4,009
		Satellite Broadcasting Services
	117,000	Eutelsat		3,023
		Co-leader in European Fixed Satellite Services
				14,541
		> Germany 3.1%
	110,000	Wincor Nixdorf		6,169
		Retail POS Systems & ATM Machines
	197,200	Rhoen-Klinikum		4,360
		Health Care Services
				10,529
		> Netherlands 2.5%
	120,162	Fugro		4,990
		Sub-sea Oilfield Services
	169,000	Imtech		3,289
		Engineering & Technical Services
				8,279
		> Spain 2.4%
	175,000	Red Electrica de Espana		7,918
		Spanish Power Grid
				7,918
		> Sweden 1.8%
	669,000	Hexagon		6,052
		Measurement Equipment
				6,052
		> Ireland 1.7%
	2,100,000	United Drug		5,834
		Irish Pharmaceutical Wholesaler & Outsourcer
				5,834

See accompanying notes to financial statements.

Columbia Acorn International Select

Statement of Investments (Unaudited), continued

Number of Shares			Value (000)
		> Switzerland 0.8%
	35,700	Kuehne & Nagel	$	2,802
		Freight Forwarding/Logistics
				2,802
		> Denmark 0.7%
	29,000	Novozymes		2,357
		Industrial Enzymes
				2,357
Europe: Total				106,764
Other Countries 24.3%
		> Canada 7.3%
	117,400	Potash Corp. of Saskatchewan		10,924
		World's Largest Producer of Potash
	1,308,000	Pacific Rubiales Energy (a)		10,784
	138,067	Pacific Rubiales Energy-Warrants (a)(b)		438
		Oil Production & Exploration in Colombia
	134,000	CCL Industries		2,646
		Leading Global Label Manufacturer
				24,792
		> United States 7.0%
	220,000	Alexion Pharmaceuticals (a)		9,046
		Biotech Focused on Orphan Diseases
	85,000	Cephalon (a)		4,815
		Specialty Pharmaceuticals for Pain, Central Nervous System & Oncology
	47,000	Diamond Offshore		3,903
		Offshore Drilling Contractor
	115,000	Atwood Oceanics (a)		2,865
		Offshore Drilling Contractor
	63,000	Oceaneering International (a)		2,848
		Provider of Sub-sea Services & Manufactured Products
				23,477
		> South Africa 4.9%
	630,000	Naspers		16,604
		Media in Africa & Other Emerging Markets
				16,604
		> Israel 3.5%
	1,203,000	Israel Chemicals		11,842
		Producer of Potash, Phosphates, Bromine & Specialty Chemicals
				11,842
		> Australia 1.6%
	1,275,000	Sino Gold (a)		5,290
		Gold Mining in The People's Republic of China
				5,290
Other Countries: Total				82,005

Number of Shares or Principal Amount (000)			Value (000)
Latin America 2.0%
		> Chile 2.0%
	182,000	Sociedad Quimica y Minera de Chile - ADR	$	6,587
		Producer of Specialty Fertilizers, Lithium & Iodine
				6,587
Latin America: Total				6,587
Total Equities: 91.7% (Cost: $293,799)				308,945
Exchange Traded Fund: 0.7%
	244,800	iShares MSCI Taiwan Index Fund		2,470
		Taiwan Exchange Traded Fund
Total Exchange Traded Fund: (Cost: $2,409)				2,470
Short-Term Obligations: 7.0%
		> Repurchase Agreement 6.5%
$	22,021	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/08, due 7/01/09 at 0.0001%, collateralized by a U.S. Treasury obligation, maturing 4/23/14, market value $22,464 (repurchase proceeds $22,021)		22,021
				22,021
		> Commercial Paper 0.5%
	1,600	Toyota Motor Credit 0.26% due 7/06/09		1,600
				1,600
Total Short-Term Obligations: (Amortized Cost: $23,621)				23,621
Total Investments: 99.4% (Cost: $319,829)(c)(d)				335,036
Cash and Other Assets Less Liabilities: 0.6%				1,901
Total Net Assets: 100.0%			$	336,937

ADR = American Depositary Receipts.

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

(a) Non-income producing security.

Additional information on these securities is as follows:

Security				Acquisition Dates				Shares				Cost				Value
Pacific Rubiales Energy-Warrants					7/12/07				138,067			$	236			$	438

(d) On June 30, 2009, the Fund's total investments were denominated in
currencies as follows:

Currency	Value		Percentage of Net Assets
Japanese Yen	$	65,796		19.5
U.S. Dollar		56,155		16.7
British Pound		48,451		14.4
Euro		47,100		14.0
Canadian Dollar		24,792		7.3
Other currencies less than 5% of total net assets		92,742		27.5
	$	335,036		99.4

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Equities
Total Asia	$	-	$	113,589	$	-	$	113,589
Total Europe		-		106,764		-		106,764
Total Other Countries		47,831		34,174		-		82,005
Total Latin America		6,587		-		-		6,587
Total Equities		54,418		254,527		-		308,945
Exchange Traded Fund		2,470		-		-		2,470
Short-Term Obligations		-		23,621		-		23,621
Total Investments		56,888		278,148		-		335,036
Total	$	56,888	$	278,148	$	-	$	335,036

The Fund's assets assigned to the Level 2 input category include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation.

See accompanying notes to financial statements.

Columbia Acorn International Select

Portfolio Diversification

At June 30, 2009, the Fund's portfolio investments as a percentage of net assets were diversified as follows:

	Value (000)		Percentage of Net Assets
> Industrial Goods & Services
Outsourcing Services	$	37,254		11.1
Industrial Materials & Specialty Chemicals		29,929		8.9
Other Industrial Services		17,154		5.1
Machinery		7,509		2.2
Electrical Components		5,705		1.7
		97,551		29.0
> Information
TV Broadcasting		16,604		4.9
Financial Processors		10,180		3.0
Internet Related		9,824		2.9
Consumer Software		8,669		2.6
Satellite Broadcasting & Services		7,032		2.1
CATV		6,823		2.0
Computer Hardware & Related Equipment		6,169		1.8
Instrumentation		6,052		1.8
Business Information & Marketing Services		3,208		1.0
		74,561		22.1
> Energy & Minerals
Mining		16,214		4.8
Oil Services		14,606		4.4
Oil & Gas Producers		11,222		3.3
		42,042		12.5
> Consumer Goods & Services
Other Consumer Services		17,973		5.3
Nondurables		9,058		2.7
Retail		7,406		2.2
Casinos & Gaming		1,291		0.4
		35,728		10.6
> Health Care
Medical Equipment & Devices		12,931		3.8
Pharmaceuticals		10,649		3.2
Health Care Services		4,360		1.3
		27,940		8.3
> Other Industries
Real Estate		9,452		2.8
Regulated Utilities		7,918		2.3
Transportation		3,662		1.1
		21,032		6.2

	Value (000)		Percentage of Net Assets
> Finance
Banks	$	10,091		3.0
		10,091		3.0
Total Equities:		308,945		91.7
Exchange Traded Fund:		2,470		0.7
Short-Term Obligations:		23,621		7.0
Total Investments:		335,036		99.4
Cash and Other Assets Less Liabilities:		1,901		0.6
Net Assets:	$	336,937		100.0

See accompanying notes to financial statements.

Columbia Acorn Select

Major Portfolio Changes in the Second Quarter (Unaudited)

	Number of Shares
	03/31/09		06/30/09
Purchases
Consumer Goods & Services
Hertz		6,500,000		7,598,000
ITT Educational Services		775,000		825,000
Princeton Review		0		871,636
Steelcase		0		2,017,127
Information
Amphenol		725,000		750,000
Novell		8,000,000		8,500,000
SBA Communications		0		505,000
VisionChina Media - ADR (China)		3,300,000		4,000,000
WNS - ADR (India)		3,800,000		3,937,425
Energy & Minerals
Canadian Solar (China)		1,600,000		1,900,000
Gran Tierra Energy (Canada)		0		2,000,000
Industrial Goods & Services
Donaldson		225,000		250,000
Finance
CIT Group		0		6,000,000
Discover Financial Services		0		1,300,076

	Number of Shares
	03/31/09		06/30/09
Sales
Consumer Goods & Services
Expedia		3,250,000		3,000,000
Knoll		400,000		0
SkillSoft - ADR		9,500,000		9,283,928
Information
American Tower		1,400,000		1,050,000
Discovery Communications		700,000		0
Discovery Communications, Series C		1,250,000		1,125,000
Globalstar		11,000,000		9,800,000
Tellabs		2,800,000		0
Energy & Minerals
Pacific Rubiales Energy (Canada)		8,122,166		7,116,666
Synthesis Energy Systems (China)		2,800,000		2,500,000
Uranium One (South Africa)		18,050,000		9,850,000
Industrial Goods & Services
Expeditors International of Washington		1,425,000		950,000
Quanta Services		2,800,000		2,500,000
Health Care
Cephalon		400,000		0

See accompanying notes to financial statements.

Columbia Acorn Select

Statement of Investments (Unaudited), June 30, 2009

Number of Shares			Value (000)
				Equities: 95.0%
Consumer Goods & Services 33.6%
		> Educational Services 13.5%
	825,000	ITT Educational Services (a)	$	83,044
		Post-secondary Degree Services
	9,283,928	SkillSoft - ADR (a)(b)		72,415
		Web-based Learning Solutions (E-Learning)
	1,700,000	Career Education (a)		42,313
		Post-secondary Education
	871,636	Princeton Review (a)		4,716
		College Preparation Courses
				202,488
		> Travel 7.1%
	7,598,000	Hertz (a)		60,708
		Largest U.S. Rental Car Operator
	3,000,000	Expedia (a)		45,330
		Online Travel Services Company
				106,038
		> Retail 6.0%
	3,350,000	Safeway		68,239
		Supermarkets
	863,000	Abercrombie & Fitch		21,912
		Teen Apparel Retailer
				90,151
		> Apparel 2.9%
	1,600,000	Coach		43,008
		Designer & Retailer of Branded Leather Accessories
				43,008
		> Casinos & Gaming 2.3%
	325,000,000	RexLot Holdings (China) (a)		25,559
		Lottery Equipment Supplier in China
	74,834,052	NagaCorp (Hong Kong)		9,878
		Casino/Entertainment Complex in Cambodia
				35,437
		> Food & Beverage 1.0%
	17,500,000	Fu Ji Food & Catering Services (China)		14,707
		Food Catering Service Provider in China
				14,707
		> Furniture & Textiles 0.8%
	2,017,127	Steelcase		11,739
		Office Furniture
				11,739
Consumer Goods & Services: Total				503,568
Information 19.3%
		> Mobile Communications 6.2%
	1,550,000	Crown Castle International (a)		37,231
		Communications Towers
	1,050,000	American Tower (a)		33,106
		Communications Towers in USA & Latin America
	505,000	SBA Communications (a)		12,393
		Communications Towers
	9,800,000	Globalstar (a)(b)(c)		10,290
		Satellite Mobile Voice & Data Carrier
				93,020

Number of Shares			Value (000)
		> Business Software 2.6%
	8,500,000	Novell (a)	$	38,505
		Directory, Operating System & Identity Management Software
				38,505
		> Computer Services 2.5%
	3,937,425	WNS - ADR (India) (a)(b)		34,965
		Offshore BPO (Business Process Outsourcing) Services
	1,334,442	Hackett Group (a)		3,109
		IT Integration & Best Practice Research
				38,074
		> Advertising 2.5%
	4,000,000	VisionChina Media - ADR (China) (a)(b)		24,440
		Advertising on Digital Screens in China's Mass Transit System
	2,350,000	China Mass Media - ADR (China) (a)(b)		12,173
		Media Planning Agency in China
				36,613
		> Computer Hardware & Related Equipment 1.6%
	750,000	Amphenol		23,730
		Electronic Connectors
				23,730
		> CATV 1.5%
	1,125,000	Discovery Communications, Series C (a)		23,096
		CATV Programming
				23,096
		> Contract Manufacturing 1.5%
	50,200,000	Sanmina-SCI (a)(b)		22,088
		Electronic Manufacturing Services
				22,088
		> Financial Processors 0.9%
	3,700,000	CardTronics (a)(b)		14,097
		Operates the World's Largest Network of ATMs
				14,097
Information: Total				289,223
Energy & Minerals 14.9%
		> Oil & Gas Producers 5.8%
	7,116,666	Pacific Rubiales Energy (Canada) (a)(d)		58,382
	1,483,334	Pacific Rubiales Energy (Canada) (a)		12,230
	2,868,750	Pacific Rubiales Energy-Warrants (Canada) (a)(d)		9,091
		Oil Production & Exploration in Colombia
	2,000,000	Gran Tierra Energy (Canada) (a)		6,964
		Oil Exploration & Production in Colombia, Peru & Argentina
				86,667
		> Oil Services 5.6%
	6,700,000	Tetra Technologies (a)(b)		53,332
		U.S.-based Service Company with Life of Field Approach
	800,000	FMC Technologies (a)		30,064
		Oil & Gas Wellhead Manufacturer
				83,396

See accompanying notes to financial statements.

Number of Shares			Value (000)
		> Alternative Energy 2.0%
	1,900,000	Canadian Solar (China) (a)(b)(c)	$	23,028
		Solar Cell & Module Manufacturer
	1,480,000	Real Goods Solar (a)(b)		3,833
		Residential Solar Energy Installer
	2,500,000	Synthesis Energy Systems (China) (a)(b)		2,875
		Owner/Operator of Gasification Plants
				29,736
		> Mining 1.5%
	9,850,000	Uranium One (South Africa) (a)		22,611
		Uranium Mines in Kazakhstan, the U.S. & Australia
				22,611
Energy & Minerals: Total				222,410
Industrial Goods & Services 12.7%
		> Outsourcing Services 3.9%
	2,500,000	Quanta Services (a)		57,825
		Electrical & Telecom Construction Services
				57,825
		> Other Industrial Services 3.1%
	950,000	Expeditors International of Washington		31,673
		International Freight Forwarder
	1,050,000	Mobile Mini (a)		15,403
		Portable Storage Units Leasing
				47,076
		> Waste Management 2.8%
	1,500,000	Waste Management		42,240
		U.S. Garbage Collection & Disposal
				42,240
		> Machinery 1.8%
	525,000	Ametek		18,155
		Aerospace/Industrial Instruments
	250,000	Donaldson		8,660
		Industrial Air Filtration
				26,815
		> Industrial Materials & Specialty Chemicals 1.1%
	1,000,000	Nalco Holding Company		16,840
		Provider of Water Treatment & Process Chemicals & Services
				16,840
Industrial Goods & Services: Total				190,796
Finance 10.7%
		> Brokerage & Money Management 6.6%
	6,015,300	MF Global (a)		35,671
		Futures Broker
	1,300,000	Eaton Vance		34,775
		Specialty Mutual Funds
	1,550,000	SEI Investments		27,962
		Mutual Fund Administration & Investment Management
				98,408

Number of Shares or Principal Amount (000)			Value (000)
		> Insurance 2.4%
	14,950,000	Conseco (a)(b)	$	35,431
		Life, Long-term Care & Medical Supplement Insurance
				35,431
		> Credit Cards 0.9%
	1,300,076	Discover Financial Services		13,352
		Credit Card Company
				13,352
		> Finance Companies 0.8%
	6,000,000	CIT Group		12,900
		Middle Market Lender, Equipment Leasing & Vendor Finance/Factoring
				12,900
Finance: Total				160,091
Other Industries 3.8%
		> Transportation 3.8%
	1,300,000	JB Hunt Transport Services		39,689
		Truck & Intermodal Carrier
	1,125,000	American Commercial Lines (a)(b)(c)		17,415
		Operator of Inland Barges/Builder of Barges & Vessels
				57,104
Other Industries: Total				57,104
Total Equities: 95.0% (Cost: $1,669,978)				1,423,192
Securities Lending Collateral: 1.2%
	17,611,150	Dreyfus Government Cash Management Fund (e) (7 day yield of 0.150%)		17,611
Securities Lending Collateral: Total 1.1% (Cost: $17,611)				17,611
Short-Term Obligations: 5.3%
		> Repurchase Agreement 4.8%
$	72,138	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.0001%, collateralized by a U.S. Government Agency obligation, maturing 3/15/16, market value $73,585 (repurchase proceeds $72,138)		72,138
				72,138

See accompanying notes to financial statements.

Columbia Acorn Select

Statement of Investments (Unaudited), continued

Principal Amount (000)			Value (000)
		> Commercial Paper 0.5%
$	7,700	Toyota Motor Credit 0.26% due 7/06/09	$	7,700
				7,700
Total Short-Term Obligations: 5.3% (Amortized Cost: $79,838)				79,838
Total Investments: 101.5% (Cost: $1,767,427)(f)				1,520,641
Obligation to Return Collateral for Securities Loaned: (1.2)%				(17,611	)
Cash and Other Assets Less Liabilities: (0.3)%				(4,691	)
Total Net Assets: 100.0%			$	1,498,339

ADR = American Depositary Receipts.

See accompanying notes to financial statements.

> Notes to Statement of Investments (dollar values in thousands)

(a) Non-income producing security.

Affiliates	Balance of Shares Held 12/31/08		Purchases/ Additions		Sales/ Reductions			Balance of Shares Held 6/30/09		Value		Dividend
American Commercial Lines		3,803,849		696,151		3,375,000	*		1,125,000	$	17,415	$	-
Canadian Solar		1,825,000		300,000		225,000			1,900,000		23,028		-
CardTronics		3,560,000		140,000		-			3,700,000		14,097		-
China Mass Media - ADR		2,350,000		-		-			2,350,000		12,173		-
Conseco		14,950,000		-		-			14,950,000		35,431		-
Globalstar		10,000,000		1,000,000		1,200,000			9,800,000		10,290		-
Real Goods Solar		1,500,000		-		20,000			1,480,000		3,833		-
Sanmina-SCI		50,200,000		-		-			50,200,000		22,088		-
SkillSoft - ADR		9,500,000		-		216,072			9,283,928		72,415		-
Synthesis Energy Systems		2,800,000		-		300,000			2,500,000		2,875		-
Tetra Technologies		6,150,000		1,050,000		500,000			6,700,000		53,332		-
VisionChina Media - ADR		3,118,900		881,100		-			4,000,000		24,440
WNS-ADR		3,100,000		843,500		6,075			3,937,425		34,965		-
Total of Affiliated Transactions		112,857,749		4,910,751		5,842,147			111,926,353	$	326,382	$	-

* Includes the effect of a 1:4 reverse stock split.

The aggregate cost and value of these companies at June 30 were $769,982 and $326,382, respectively. Investments in affiliated companies represented 21.8% of total net assets at June 30, 2009.

(c) All or a portion of this security was on loan at June 30, 2009. The total market value of securities on loan at June 30, 2009 was $16,936.

Additional information on these securities is as follows:

Security	Acquisition Dates	Shares		Cost		Value
Pacific Rubiales Energy	7/12/07-8/22/07		7,116,666	$	30,391	$	58,382
Pacific Rubiales Energy-Warrants	7/12/07		2,868,750		4,910		9,091
				$	35,301	$	67,473

(e) Investment made with cash collateral received from securities lending activity.

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Equities
Total Consumer Goods & Services	$	453,424	$	50,144	$	-	$	503,568
Total Information		289,223		-		-		289,223
Total Energy & Minerals		154,937		67,473		-		222,410
Total Industrial Goods & Services		190,796		-		-		190,796
Total Finance		160,091		-		-		160,091
Total Other Industries		57,104		-		-		57,104
Total Equities		1,305,575		117,617		-		1,423,192
Securities Lending Collateral		17,611		-		-		17,611
Short-Term Obligations		-		79,838		-		79,838
Total Investments		1,323,186		197,455		-		1,520,641
Total	$	1,323,186	$	197,455	$	-	$	1,520,641

The Fund's assets assigned to the Level 2 input category include certain foreign securities for which a third party statistical pricing service may be employed for purposes of fair market valuation.

See accompanying notes to financial statements.

Columbia Thermostat Fund

Statement of Investments (Unaudited), June 30, 2009

Number of Shares or Principal Amount (000)			Value (000)
		> Stock Funds: 99.5%
	3,482,959	Columbia Large Cap Enhanced Core Fund, Class Z	$	31,242
	2,474,587	Columbia Dividend Income Fund, Class Z		24,869
	968,355	Columbia Acorn Fund, Class Z		18,825
	681,187	Columbia Acorn International, Class Z		18,753
	1,323,292	Columbia Marsico Growth Fund, Class Z		18,579
	712,612	Columbia Acorn Select, Class Z		12,471
Total Stock Funds (Cost: $158,610)				124,739
Short-Term Obligations: 0.7%
		> Repurchase Agreements: 0.7%
$	446	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.001%, collateralized by a U.S. Government Agency obligation, maturing 8/20/13 market value $455 (repurchase proceeds $446)		446
	407	Repurchase Agreement with Fixed Income Clearing Corp., dated 6/30/09, due 7/01/09 at 0.0001%, collateralized by a U.S. Government Agency obligation, maturing 4/23/14 market value $415 (repurchase proceeds $407)		407
Total Short-Term Obligations (Cost: $853)				853
Total Investments: 100.2% (Cost: $159,463)(a)				125,592
Cash and Other Assets Less Liabilities: (0.2)%				(252	)
Total Net Assets: 100.0%			$	125,340

See accompanying notes to financial statements.

> Notes to Statements of Investments (dollar values in thousands)

The following table summarizes the inputs used, as of June 30, 2009, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Investment Companies	$	124,739	$	-	$	-	$	124,739
Short-Term Obligations		-		853		-		853
Total Investments		124,739		853		-		125,592
Total	$	124,739	$	853	$	-	$	125,592

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Assets and Liabilities (Unaudited)

June 30, 2009	Columbia Acorn Fund			Columbia Acorn International			Columbia Acorn USA			Columbia Acorn International Select			Columbia Acorn Select			Columbia Thermostat Fund
(in thousands)
Assets:
Unaffiliated investments, at cost	$	7,910,206		$	3,004,096		$	1,144,180		$	319,829		$	997,445		$	853
Affiliated investments, at cost (See Note 4)		3,111,124			59,544			16,983			—			769,982			158,610
Unaffiliated investments, at value (including securities on loan: Columbia Acorn Fund $129,784; Columbia Acorn International $1,905; Columbia Acorn USA $23,954; Columbia Acorn International Select $–; Columbia Acorn Select $16,936; Columbia Thermostat Fund $–)	$	9,027,810		$	3,243,462		$	1,105,685		$	335,036		$	1,194,259		$	853
Affiliated investments, at value (See Note 4)		2,822,304			69,240			10,304			—			326,382			124,739
Cash		3,248			1			—			—	*		1			—	*
Foreign currency (cost: Columbia Acorn Fund $4,116; Columbia Acorn International $22,027; Columbia Acorn International Select $335; Columbia Acorn Select $–)		4,174			22,008			—			332			—			—
Unrealized appreciation on forward foreign currency exchange contracts		—			3,212			—			—			—			—
Receivable for:
Investments sold		26,664			8,714			3,743			1,445			820			—
Fund shares sold		10,208			5,488			1,472			2,199			1,433			141
Dividends and interest		6,441			4,834			447			312			524			—
Securities lending income		197			12			29			—			93			—
Foreign tax reclaims		269			1,679			—			127			—			—
Expense reimbursement due from Advisor		—			—			—			1			—			48
Trustees' Deferred Compensation Investments		2,506			699			193			—			224			—
Other assets		29			9			2			—	*		5			5
Total Assets		11,903,850			3,359,358			1,121,875			339,452			1,523,741			125,786
Liabilities:
Payable to custodian bank		—			—			23			—			—			—
Collateral on securities loaned		133,395			1,944			24,650			—			17,611			—
Expense reimbursement due to Advisor		—			—			—			—			5			—
Unrealized depreciation on forward foreign currency exchange contracts		—			5,646			—			—			—			—
Payable for:
Investments purchased		28,350			6,876			4,585			1,357			1,870			—
Fund shares redeemed		33,574			4,137			1,388			733			3,615			286
Management fee		6,264			2,119			786			254			1,028			10
Administration fee		432			121			40			12			56			5
12b-1 Service and Distribution fees		1,320			160			65			22			196			45
Reports to shareholders		863			298			92			25			252			41
Deferred Trustees' fees		2,506			699			193			33			224			22
Transfer agent fees		3,057			465			247			29			521			37
Trustees' fees		4			1			1			—	*		4			—	*
Custody fees		287			846			9			33			—			—
Deferred foreign capital gains tax payable		—			2,496			—			—			—			—
Other liabilities		4			48			10			17			20			—
Total Liabilities		210,056			25,856			32,089			2,515			25,402			446
Net Assets	$	11,693,794		$	3,333,502		$	1,089,786		$	336,937		$	1,498,339		$	125,340
Composition of Net Assets:
Paid in capital	$	11,363,927		$	3,696,881		$	1,264,123		$	400,024		$	1,903,392		$	180,354
Undistributed/(overdistributed) net investment income (Accumulated net investment loss)		10,048			28,563			(1,564	)		1,132			(4,758	)		472
Accumulated net realized gain/(loss)		(509,030	)		(636,081	)		(127,599	)		(79,429	)		(153,509	)		(21,615	)
Net unrealized appreciation/(depreciation) on:
Investments		828,784			249,062			(45,174	)		15,207			(246,786	)		(33,871	)
Foreign capital gains tax		—			(2,496	)		—			—			—			—
Foreign currency translations		65			(2,427	)		—			3			—			—
Net Assets	$	11,693,794		$	3,333,502		$	1,089,786		$	336,937		$	1,498,339		$	125,340
Net asset value per share – Class A (a)	$	18.88		$	27.47		$	17.16		$	19.52		$	17.09		$	8.88
(Net assets/shares)		($2,340,341/123,982)			($414,663/15,096)			($144,270/8,409)			($60,654/3,107)			($423,925/24,800)			($38,497/4,335)
Maximum offering price per share – Class A (b)	$	20.03		$	29.14		$	18.21		$	20.71		$	18.14		$	9.42
(Net asset value per share/front- end sales charge)		($18.88/0.9425)			($27.47/0.9425)			($17.16/0.9425)			($19.52/0.9425)			($17.09/0.9425)			($8.88/0.9425)
Net asset value and offering price per share – Class B (a)	$	17.71		$	26.82		$	16.11		$	18.71		$	16.10		$	8.93
(Net assets/shares)		($521,503/29,446)			($37,517/1,399)			($21,287/1,322)			($3,691/197)			($76,156/4,729)			($32,245/3,611)
Net asset value and offering price per share – Class C (a)	$	17.57		$	26.74		$	16.01		$	18.62		$	16.00		$	8.92
(Net assets/shares)		($618,461/35,197)			($65,900/2,465)			($25,641/1,602)			($9,562/513)			($74,894/4,682)			($19,523/2,188)
Net asset value and offering price per share – Class Z (c)	$	19.44		$	27.53		$	17.71		$	19.70		$	17.50		$	8.79
(Net assets/shares)		($8,213,489/422,483)			($2,815,422/102,280)			($898,588/50,731)			($263,030/13,355)			($923,364/52,762)			($35,075/3,989)

(a) Redemption price per share is equal to net asset value less any applicable contingent deferred sales charge and redemption fee.

(b) On sales of $50,000 or more the offering price is reduced.

* Rounds to less than $500.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Operations (Unaudited)
For the Six Months Ended June 30, 2009

(in thousands)	Columbia Acorn Fund			Columbia Acorn International			Columbia Acorn USA			Columbia Acorn International Select			Columbia Acorn Select			Columbia Thermostat Fund
Investment Income:
Dividend income	$	55,015		$	50,215		$	3,987		$	3,849		$	3,540		$	—
Dividend income from affiliates (See Note 4)		8,712			910			—			—			—			—
Dividends from affiliated investment company shares (See Note 4)		—			—			—			—			—			921
Interest income		334			94			19			10			40			—	*
Securitites lending income		197			12			29			—			93			—
		64,258			51,231			4,035			3,859			3,673			921
Foreign taxes withheld		(1,195	)		(4,175	)		(1	)		(328	)		—			—
Total Investment Income		63,063			47,056			4,034			3,531			3,673			921
Expenses:
Management fee		33,835			10,922			4,143			1,225			5,431			60
Administration fee		2,360			629			214			58			297			27
12b-1 Service and Distribution fees:
Class A		2,613			435			163			60			473			46
Class B		1,918			129			78			14			260			119
Class C		2,858			287			118			45			335			100
Transfer agent fees:
Class A		1,250			362			72			35			333			41
Class B		774			74			37			10			141			45
Class C		535			82			22			12			88			26
Class Z		1,833			655			238			44			267			9
Custody fees		487			1,321			22			70			88			—
Trustees' fees		480			130			43			14			64			8
Registration and blue sky fees		79			51			34			37			42			28
Reports to shareholders		1,130			462			171			73			316			82
Chief compliance officer expenses (See Note 4)		290			75			26			7			36			3
Other expenses		457			165			60			42			89			25
Total expenses		50,899			15,779			5,441			1,746			8,260			619
Less custody fees paid indirectly		—	*		—	*		—	*		—	*		—	*		—
Less reimbursement of expenses by Investment Advisor		—			—			—			(5	)		(9	)		(204	)
Net Expenses		50,899			15,779			5,441			1,741			8,251			415
Net Investment Income/(Loss)		12,164			31,277			(1,407	)		1,790			(4,578	)		506
Net Realized and Unrealized Gain (Loss) on Portfolio Positions:
Net realized gain/(loss) on:
Unaffiliated investments		(390,602	)		(254,864	)		(23,665	)		(31,779	)		(38,924	)		—
Affiliated investments (See Note 4)		(952	)		(3,830	)		—			—			(17,425	)		(11,816	)
Foreign currency transactions and forward foreign currency exchange contracts		(163	)		(1,856	)		—			(75	)		488			—
Net realized gain/(loss)		(391,717	)		(260,550	)		(23,665	)		(31,854	)		(55,861	)		(11,816	)
Net change in net unrealized appreciation/(depreciation) on:
Unaffiliated investments		1,098,443			774,311			110,717			61,179			343,493			—
Affiliated investments (See Note 4)		271,729			21,926			(1,892	)		—			6,519			18,571
Foreign currency translations and forward foreign currency exchange contracts		63			971			—			(13	)		(3	)		—
Foreign capital gains tax		—			(2,496	)		—			—			—			—
Net change in unrealized appreciation/ (depreciation)		1,370,235			794,712			108,825			61,166			350,009			18,571
Net realized and unrealized gain		978,518			534,162			85,160			29,312			294,148			6,755
Net Increase in Net Assets resulting from Operations	$	990,682		$	565,439		$	83,753		$	31,102		$	289,570		$	7,261

* Rounds to less than $500.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Changes in Net Assets

	Columbia Acorn Fund						Columbia Acorn International						Columbia Acorn USA
Increase (Decrease) in Net Assets	(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,
(in thousands)	2009			2008			2009			2008			2009			2008
Operations:
Net investment income/(loss)	$	12,164		$	12,367		$	31,277		$	76,400		$	(1,407	)	$	(5,465	)
Net realized gain/(loss) on investments,foreign currency transactions and forward foreign currency exchange contracts		(391,717	)		(11,712	)		(260,550	)		(378,865	)		(23,665	)		(102,173	)
Net realized gain/(loss) on affiliated investments and distributions from affiliated investment company shares		—			—			—			—			—			—
Net change in net unrealized appreciation/(depreciation) on investments, foreign currency translations, forward foreign currency exchange contracts and foreign capital gains tax		1,370,235			(7,343,366	)		794,712			(2,403,090	)		108,825			(495,968	)
Net change in net unrealized appreciation/(depreciation) on affiliated investment company shares		—			—			—			—			—			—
Net Increase/(Decrease) from Operations		990,682			(7,342,711	)		565,439			(2,705,555	)		83,753			(603,606	)
Distributions to Shareholders From:
Net investment income – Class A		—			—			(6,101	)		(1,020	)		—			—
Net realized gain – Class A		—	*		(91,100	)		—			(9,807	)		—			(8,248	)
Net investment income – Class B		—			—			(290	)		—	*		—			—
Net realized gain – Class B		—	*		(26,893	)		—			(1,332	)		—			(1,748	)
Net investment income – Class C		—			—			(348	)		—	*		—			—
Net realized gain – Class C		—			(28,315	)		—			(2,146	)		—			(1,740	)
Net investment income – Class Z		—			(6,088	)		(53,466	)		(23,593	)		—			—
Net realized gain – Class Z		—	*		(284,695	)		—			(68,973	)		—			(41,787	)
Total Distributions to Shareholders		—			(437,091	)		(60,205	)		(106,871	)		—			(53,523	)
Share Transactions:
Subscriptions – Class A		293,596			612,669			59,159			277,346			32,218			53,928
Distributions reinvested – Class A		—	*		83,711			5,737			9,979			—			7,538
Redemptions – Class A		(363,945	)		(1,151,023	)		(77,603	)		(207,715	)		(35,190	)		(69,749	)
Net Increase/(Decrease) – Class A		(70,349	)		(454,643	)		(12,707	)		79,610			(2,972	)		(8,283	)
Subscriptions – Class B		102			1,991			—			1,704			5			71
Distributions reinvested – Class B		—			24,675			278			1,209			—			1,615
Redemptions – Class B		(99,550	)		(255,304	)		(7,739	)		(23,974	)		(3,666	)		(11,765	)
Net Decrease – Class B		(99,448	)		(228,638	)		(7,461	)		(21,061	)		(3,661	)		(10,079	)
Subscriptions – Class C		25,737			62,517			3,110			20,234			957			3,931
Distributions reinvested – Class C		—			22,379			265			1,596			—			1,523
Redemptions – Class C		(76,956	)		(287,537	)		(10,606	)		(43,103	)		(2,805	)		(10,090	)
Net Increase/(Decrease) – Class C		(51,219	)		(202,641	)		(7,231	)		(21,273	)		(1,848	)		(4,636	)
Subscriptions – Class Z		706,723			1,526,416			213,802			664,727			153,038			213,395
Distributions reinvested – Class Z		—			251,789			38,423			64,910			—			37,687
Redemptions – Class Z		(653,809	)		(2,162,613	)		(237,241	)		(912,602	)		(82,920	)		(190,501	)
Net Increase/(Decrease) – Class Z		52,914			(384,408	)		14,984			(182,965	)		70,118			60,581
Net Increase/(Decrease) from Share Transactions		(168,102	)		(1,270,330	)		(12,415	)		(145,689	)		61,637			37,583
Redemption Fees		—			—			116			354			—			—
Total Increase/(Decrease) in Net Assets		822,580			(9,050,132	)		492,935			(2,957,761	)		145,390			(619,546	)
Net Assets:
Beginning of period		10,871,214			19,921,346			2,840,567			5,798,328			944,396			1,563,942
End of period	$	11,693,794		$	10,871,214		$	3,333,502		$	2,840,567		$	1,089,786		$	944,396
Undistributed/(Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)	$	10,048		$	(2,116	)	$	28,563		$	57,491		$	(1,564	)	$	(157	)

* Rounds to less than $500.

See accompanying notes to financial statements.

	Columbia Acorn International Select						Columbia Acorn Select						Columbia Thermostat Fund
Increase (Decrease) in Net Assets	(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,
(in thousands)	2009			2008			2009			2008			2009			2008
Operations:
Net investment income/(loss)	$	1,790		$	2,451		$	(4,578	)	$	(17,307	)	$	506		$	3,146
Net realized gain/(loss) on investments,foreign currency transactions and forward foreign currency exchange contracts		(31,854	)		(46,780	)		(55,861	)		(87,624	)		—			—
Net realized gain/(loss) on affiliated investments and distributions from affiliated investment company shares		—			—			—			—			(11,816	)		(9,015	)
Net change in net unrealized appreciation/(depreciation) on investments, foreign currency translations, forward foreign currency exchange contracts and foreign capital gains tax		61,166			(101,043	)		350,009			(1,330,289	)		—			—
Net change in net unrealized appreciation/(depreciation) on affiliated investment company shares		—			—			—			—			18,571			(58,979	)
Net Increase/(Decrease) from Operations		31,102			(145,372	)		289,570			(1,435,220	)		7,261			(64,848	)
Distributions to Shareholders From:
Net investment income – Class A		(456	)		—			—			—			(7	)		(1,051	)
Net realized gain – Class A		—			(984	)		—			(25,410	)		—			(337	)
Net investment income – Class B		—			—			—			—			—			(657	)
Net realized gain – Class B		—			(189	)		—			(4,641	)		—			(371	)
Net investment income – Class C		—			—			—			—			—			(361	)
Net realized gain – Class C		—			(288	)		—			(4,551	)		—			(201	)
Net investment income – Class Z		(3,077	)		(280	)		—			—			(115	)		(1,140	)
Net realized gain – Class Z		—			(3,600	)		—			(39,523	)		—			(301	)
Total Distributions to Shareholders		(3,533	)		(5,341	)		—			(74,125	)		(122	)		(4,419	)
Share Transactions:
Subscriptions – Class A		21,075			47,637			49,937			131,376			3,418			21,460
Distributions reinvested – Class A		440			901			—			23,381			6			1,269
Redemptions – Class A		(12,187	)		(21,936	)		(103,487	)		(377,780	)		(8,180	)		(14,939	)
Net Increase/(Decrease) – Class A		9,328			26,602			(53,550	)		(223,023	)		(4,756	)		7,790
Subscriptions – Class B		—			271			7			388			—			2,089
Distributions reinvested – Class B		—			170			—			4,147			—			943
Redemptions – Class B		(992	)		(3,345	)		(11,619	)		(41,288	)		(6,281	)		(14,056	)
Net Decrease – Class B		(992	)		(2,904	)		(11,612	)		(36,753	)		(6,281	)		(11,024	)
Subscriptions – Class C		959			7,847			2,400			8,177			807			17,881
Distributions reinvested – Class C		—			248			—			3,639			—			510
Redemptions – Class C		(1,893	)		(4,044	)		(12,442	)		(51,407	)		(6,477	)		(8,717	)
Net Increase/(Decrease) – Class C		(934	)		4,051			(10,042	)		(39,591	)		(5,670	)		9,674
Subscriptions – Class Z		83,230			175,091			126,122			387,091			1,348			23,041
Distributions reinvested – Class Z		833			1,768			—			29,748			106			1,339
Redemptions – Class Z		(29,026	)		(84,177	)		(161,949	)		(373,486	)		(3,619	)		(8,008	)
Net Increase/(Decrease) – Class Z		55,037			92,682			(35,827	)		43,353			(2,165	)		16,372
Net Increase/(Decrease) from Share Transactions		62,439			120,431			(111,031	)		(256,014	)		(18,872	)		22,812
Redemption Fees		23			171			—			—			—			—
Total Increase/(Decrease) in Net Assets		90,031			(30,111	)		178,539			(1,765,359	)		(11,733	)		(46,455	)
Net Assets:
Beginning of period		246,906			277,017			1,319,800			3,085,159			137,073			183,528
End of period	$	336,937		$	246,906		$	1,498,339		$	1,319,800		$	125,340		$	137,073
Undistributed/(Overdistributed) Net Investment Income or (Accumulated Net Investment Loss)	$	1,132		$	2,875		$	(4,758	)	$	(180	)	$	472		$	88

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Changes in Net Assets, continued

	Columbia Acorn Fund						Columbia Acorn International						Columbia Acorn USA
Changes in Shares of Beneficial Interest:	(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,
(in thousands)	2009			2008			2009			2008			2009			2008
Subscriptions – Class A		17,391			26,521			2,525			8,030			2,119			2,597
Shares issued in reinvestment and capital gains – Class A		—			3,428			208			248			—			302
Less shares redeemed – Class A		(22,419	)		(49,918	)		(3,567	)		(6,693	)		(2,303	)		(3,306	)
Net Increase/(Decrease) – Class A		(5,028	)		(19,969	)		(834	)		1,585			(184	)		(407	)
Subscriptions – Class B		5			80			—			44			—	*		3
Shares issued in reinvestment and capital gains – Class B		—			1,065			10			30			—			68
Less shares redeemed – Class B		(6,437	)		(11,645	)		(358	)		(768	)		(256	)	��	(573	)
Net Decrease – Class B		(6,432	)		(10,500	)		(348	)		(694	)		(256	)		(502	)
Subscriptions – Class C		1,631			3,082			133			569			66			219
Shares issued in reinvestment and capital gains – Class C		—			975			10			41			—			65
Less shares redeemed – Class C		(5,125	)		(13,528	)		(499	)		(1,414	)		(203	)		(514	)
Net Increase/(Decrease) – Class C		(3,494	)		(9,471	)		(356	)		(804	)		(137	)		(230	)
Subscriptions – Class Z		40,996			63,561			8,828			19,040			9,698			9,874
Shares issued in reinvestment and capital gains – Class Z		—			10,170			1,391			1,609			—			1,466
Less shares redeemed – Class Z		(39,033	)		(93,561	)		(10,481	)		(30,912	)		(5,233	)		(8,493	)
Net Increase/(Decrease) – Class Z		1,963			(19,830	)		(262	)		(10,263	)		4,465			2,847
Net Increase/(Decrease) in Shares of Beneficial Interest		(12,991	)		(59,770	)		(1,800	)		(10,176	)		3,888			1,708

* Rounds to less than 500.

See accompanying notes to financial statements.

	Columbia Acorn International Select						Columbia Acorn Select						Columbia Thermostat Fund
Changes in Shares of Beneficial Interest:	(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,			(Unaudited) Six months ended June 30,			Year ended December 31,
(in thousands)	2009			2008			2009			2008			2009			2008
Subscriptions – Class A		1,214			1,986			3,524			6,192			431			1,952
Shares issued in reinvestment and capital gains – Class A		23			30			—			901			1			147
Less shares redeemed – Class A		(716	)		(959	)		(7,473	)		(18,425	)		(1,067	)		(1,454	)
Net Increase/(Decrease) – Class A		521			1,057			(3,949	)		(11,332	)		(635	)		645
Subscriptions – Class B		—			10			—	*		16			—			176
Shares issued in reinvestment and capital gains – Class B		—			6			—			168			—			104
Less shares redeemed – Class B		(62	)		(149	)		(892	)		(2,059	)		(796	)		(1,344	)
Net Decrease – Class B		(62	)		(133	)		(892	)		(1,875	)		(796	)		(1,064	)
Subscriptions – Class C		58			317			170			469			100			1,558
Shares issued in reinvestment and capital gains – Class C		—			9			—			148			—			56
Less shares redeemed – Class C		(116	)		(183	)		(973	)		(2,581	)		(840	)		(861	)
Net Increase/(Decrease) – Class C		(58	)		143			(803	)		(1,964	)		(740	)		753
Subscriptions – Class Z		4,783			7,667			8,532			17,670			175			1,994
Shares issued in reinvestment and capital gains – Class Z		42			58			—			1,123			12			153
Less shares redeemed – Class Z		(1,706	)		(3,845	)		(11,196	)		(18,669	)		(472	)		(783	)
Net Increase/(Decrease) – Class Z		3,119			3,880			(2,664	)		124			(285	)		1,364
Net Increase/(Decrease) in Shares of Beneficial Interest		3,520			4,947			(8,308	)		(15,047	)		(2,456	)		1,698

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Financial Highlights

Columbia Acorn Fund

Class A Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	17.22		$	28.87		$	29.02		$	27.57		$	25.93		$	22.20
Income from Investment Operations
Net investment income/(loss) (a)		0.01			(0.01	)		0.05	(b)		0.05			0.07			(0.05	)
Net realized and unrealized gain/(loss)		1.65			(10.98	)		2.13			3.82			3.20			4.69
Total from Investment Operations		1.66			(10.99	)		2.18			3.87			3.27			4.64
Less Distributions to Shareholders
From net investment income		—			—			(0.03	)		(0.04	)		(0.07	)		—
From net realized gains		—			(0.66	)		(2.30	)		(2.38	)		(1.56	)		(0.91	)
Total Distributions to Shareholders		—			(0.66	)		(2.33	)		(2.42	)		(1.63	)		(0.91	)
Net Asset Value, End of Period	$	18.88		$	17.22		$	28.87		$	29.02		$	27.57		$	25.93
Total Return (c)		9.64	%(d)		(38.72	)%		7.39	%(e)(f)		14.13	%(e)		12.76	%(e)		21.05	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		1.12	%(h)		1.05	%		1.02	%		1.02	%		1.03	%		1.20	%
Net investment income/(loss) (g)		0.09	%(h)		(0.04	)%		0.17	%		0.17	%		0.28	%		(0.21	)%
Waiver/Reimbursement		—			—			0.01	%		0.02	%		0.02	%		0.02	%
Portfolio turnover rate		14	%(d)		21	%		20	%		22	%		16	%		20	%
Net assets at end of period (000s)	$	2,340,341		$	2,221,100		$	4,300,920		$	4,067,868		$	3,349,461		$	2,669,936

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.03 per share.

(c) Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

Class B Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	16.21		$	27.39		$	27.78		$	26.61		$	25.19		$	21.75
Income from Investment Operations
Net investment loss (a)		(0.05	)		(0.15	)		(0.11	)(b)		(0.13	)		(0.11	)		(0.22	)
Net realized and unrealized gain/(loss)		1.55			(10.37	)		2.02			3.68			3.09			4.57
Total from Investment Operations		1.50			(10.52	)		1.91			3.55			2.98			4.35
Less Distributions to Shareholders
From net realized gains		—			(0.66	)		(2.30	)		(2.38	)		(1.56	)		(0.91	)
Total Distributions to Shareholders		—			(0.66	)		(2.30	)		(2.38	)		(1.56	)		(0.91	)
Net Asset Value, End of Period	$	17.71		$	16.21		$	27.39		$	27.78		$	26.61		$	25.19
Total Return (c)		9.25	%(d)		(39.11	)%		6.76	%(e)(f)		13.43	%(e)		11.98	%(e)		20.15	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		1.80	%(h)		1.65	%		1.59	%		1.66	%		1.72	%		1.95	%
Net investment loss (g)		(0.60	)%(h)		(0.64	)%		(0.39	)%		(0.48	)%		(0.42	)%		(0.96	)%
Waiver/Reimbursement		—			—			0.01	%		0.02	%		0.02	%		0.02	%
Portfolio turnover rate		14	%(d)		21	%		20	%		22	%		16	%		20	%
Net assets at end of period (000s)	$	521,503		$	581,587		$	1,270,292		$	1,404,165		$	1,422,580		$	1,399,135

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.03 per share.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

Class C Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	16.09		$	27.25		$	27.70		$	26.58		$	25.18		$	21.75
Income from Investment Operations
Net investment loss (a)		(0.06	)		(0.19	)		(0.18	)(b)		(0.17	)		(0.13	)		(0.22	)
Net realized and unrealized gain/(loss)		1.54			(10.31	)		2.03			3.67			3.09			4.56
Total from Investment Operations		1.48			(10.50	)		1.85			3.50			2.96			4.34
Less Distributions to Shareholders
From net realized gains		—			(0.66	)		(2.30	)		(2.38	)		(1.56	)		(0.91	)
Total Distributions to Shareholders		—			(0.66	)		(2.30	)		(2.38	)		(1.56	)		(0.91	)
Net Asset Value, End of Period	$	17.57		$	16.09		$	27.25		$	27.70		$	26.58		$	25.18
Total Return (c)		9.20	%(d)		(39.23	)%		6.56	%(e)(f)		13.25	%(e)		11.90	%(e)		20.11	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		1.94	%(h)		1.83	%		1.79	%		1.80	%		1.82	%		1.95	%
Net investment loss (g)		(0.73	)%(h)		(0.82	)%		(0.60	)%		(0.61	)%		(0.51	)%		(0.96	)%
Waiver/Reimbursement		—			—			0.00	%(i)		0.02	%		0.02	%		0.02	%
Portfolio turnover rate		14	%(d)		21	%		20	%		22	%		16	%		20	%
Net assets at end of period (000s)	$	618,461		$	622,665		$	1,312,243		$	1,345,520		$	1,220,339		$	1,083,006

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.03 per share.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

(i) Rounds to less than 0.01%.

See accompanying notes to financial statements.

Columbia Acorn International

Class A Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	23.03		$	43.42		$	40.07		$	33.20		$	28.75		$	22.45
Income from Investment Operations
Net investment income (a)		0.22			0.47			0.27			0.23			0.22			0.14
Net realized and unrealized gain/(loss)		4.63			(20.20	)		6.52			10.87			5.84			6.31
Total from Investment Operations		4.85			(19.73	)		6.79			11.10			6.06			6.45
Less Distributions to Shareholders
From net investment income		(0.41	)		(0.06	)		(0.08	)		(0.32	)		(0.53	)		(0.15	)
From net realized gains		—			(0.60	)		(3.36	)		(3.91	)		(1.08	)		—
Total Distributions to Shareholders		(0.41	)		(0.66	)		(3.44	)		(4.23	)		(1.61	)		(0.15	)
Redemption Fees
Redemption fees added to paid in capital (a)(b)		0.00			0.00			0.00			0.00			0.00			0.00
Net Asset Value, End of Period	$	27.47		$	23.03		$	43.42		$	40.07		$	33.20		$	28.75
Total Return (c)		21.05	%(d)		(46.09	)%		16.90	%(e)		34.16	%(e)		21.42	%(e)		28.91	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.45	%(g)		1.31	%		1.23	%		1.24	%		1.30	%		1.48	%
Net investment income (f)		1.91	%(g)		1.36	%		0.60	%		0.61	%		0.72	%		0.61	%
Waiver/Reimbursement		—			—			0.00	%(h)		0.01	%		0.02	%		0.02	%
Portfolio turnover rate		20	%(d)		38	%		28	%		31	%		27	%		40	%
Net assets at end of period (000s)	$	414,663		$	366,820		$	622,901		$	313,401		$	142,204		$	70,582

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Rounds to less than $0.01 per share.

(c) Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g) Annualized.

(h) Rounds to less than 0.01%.

Class B Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	22.41		$	42.46		$	39.39		$	32.71		$	28.18		$	22.07
Income from Investment Operations
Net investment income/(loss) (a)		0.13			0.27			0.04			(0.00	)(b)		0.02			(0.04	)
Net realized and unrealized gain/(loss)		4.48			(19.72	)		6.39			10.66			5.73			6.19
Total from Investment Operations		4.61			(19.45	)		6.43			10.66			5.75			6.15
Less Distributions to Shareholders
From net investment income		(0.20	)		—			(0.00	)(b)		(0.07	)		(0.14	)		(0.04	)
From net realized gains		—			(0.60	)		(3.36	)		(3.91	)		(1.08	)		—
Total Distributions to Shareholders		(0.20	)		(0.60	)		(3.36	)		(3.98	)		(1.22	)		(0.04	)
Redemption Fees
Redemption fees added to paid in capital (a)(b)		0.00			0.00			0.00			0.00			0.00			0.00
Net Asset Value, End of Period	$	26.82		$	22.41		$	42.46		$	39.39		$	32.71		$	28.18
Total Return (c)		20.59	%(d)		(46.41	)%		16.25	%(e)		33.26	%(e)		20.57	%(e)		27.91	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		2.17	%(g)		1.90	%		1.81	%		1.89	%		2.01	%		2.27	%
Net investment income/(loss) (f)		1.17	%(g)		0.77	%		0.08	%		(0.01	)%		0.08	%		(0.18	)%
Waiver/Reimbursement		—			—			0.01	%		0.02	%		0.02	%		0.02	%
Portfolio turnover rate		20	%(d)		38	%		28	%		31	%		27	%		40	%
Net assets at end of period (000s)	$	37,517		$	39,153		$	103,631		$	94,165		$	73,572		$	54,752

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Rounds to less than $0.01 per share.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g) Annualized.

Class C Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	22.30		$	42.32		$	39.35		$	32.68		$	28.19		$	22.06
Income from Investment Operations
Net investment income/(loss) (a)		0.12			0.21			(0.06	)		(0.05	)		(0.00	)(b)		(0.03	)
Net realized and unrealized gain/(loss)		4.46			(19.63	)		6.39			10.66			5.71			6.20
Total from Investment Operations		4.58			(19.42	)		6.33			10.61			5.71			6.17
Less Distributions Declared to Shareholders
From net investment income		(0.14	)		—			(0.00	)(b)		(0.03	)		(0.14	)		(0.04	)
From net realized gains		—			(0.60	)		(3.36	)		(3.91	)		(1.08	)		—
Total Distributions Declared to Shareholders		(0.14	)		(0.60	)		(3.36	)		(3.94	)		(1.22	)		(0.04	)
Redemption Fees
Redemption fees added to paid in capital (a)(b)		0.00			0.00			0.00			0.00			0.00			0.00
Net Asset Value, End of Period	$	26.74		$	22.30		$	42.32		$	39.35		$	32.68		$	28.19
Total Return (c)		20.54	%(d)		(46.50	)%		16.01	%(e)		33.14	%(e)		20.45	%(e)		28.01	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		2.27	%(g)		2.08	%		1.99	%		2.01	%		2.09	%		2.24	%
Net investment income/(loss) (f)		1.07	%(g)		0.60	%		(0.14	)%		(0.14	)%		(0.01	)%		(0.15	)%
Waiver/Reimbursement		—			—			0.00	%(h)		0.01	%		0.02	%		0.02	%
Portfolio turnover rate		20	%(d)		38	%		28	%		31	%		27	%		40	%
Net assets at end of period (000s)	$	65,900		$	62,906		$	153,416		$	99,425		$	47,325		$	30,547

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Rounds to less than $0.01 per share.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g) Annualized.

(h) Rounds to less than 0.01%.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn USA

Class A Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	15.90		$	27.23		$	28.02		$	26.52		$	24.77		$	20.74
Income from Investment Operations
Net investment loss (a)		(0.04	)		(0.14	)		(0.09	)(b)		(0.10	)		(0.01	)		(0.24	)
Net realized and unrealized gain/(loss)		1.30			(10.23	)		1.01			2.21			3.13			4.41
Total from Investment Operations		1.26			(10.37	)		0.92			2.11			3.12			4.17
Less Distributions to Shareholders
From net realized gains		—			(0.96	)		(1.71	)		(0.61	)		(1.37	)		(0.14	)
Net Asset Value, End of Period	$	17.16		$	15.90		$	27.23		$	28.02		$	26.52		$	24.77
Total Return (c)		7.92	%(d)		(39.38	)%		3.18	%(e)(f)		7.95	%(e)		12.68	%(e)		20.12	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		1.36	%(h)		1.29	%		1.25	%		1.26	%		1.31	%		1.51	%
Net investment loss (g)		(0.50	)%(h)		(0.60	)%		(0.29	)%		(0.35	)%		(0.02	)%		(1.08	)%
Waiver/Reimbursement		—			—			0.00	%(i)		0.01	%		0.01	%		0.02	%
Portfolio turnover rate		16	%(d)		23	%		21	%		13	%		13	%		18	%
Net assets at end of period (000s)	$	144,270		$	136,597		$	245,085		$	245,552		$	168,922		$	112,509

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.09 per share.

(c) Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

(i) Rounds to less than 0.01%.

Class B Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	14.98		$	25.87		$	26.87		$	25.61		$	24.14		$	20.36
Income from Investment Operations
Net investment loss (a)		(0.09	)		(0.27	)		(0.25	)(b)		(0.27	)		(0.18	)		(0.39	)
Net realized and unrealized gain/(loss)		1.22			(9.66	)		0.96			2.14			3.02			4.31
Total from Investment Operations		1.13			(9.93	)		0.71			1.87			2.84			3.92
Less Distributions to Shareholders
From net realized gains		—			(0.96	)		(1.71	)		(0.61	)		(1.37	)		(0.14	)
Net Asset Value, End of Period	$	16.11		$	14.98		$	25.87		$	26.87		$	25.61		$	24.14
Total Return (c)		7.54	%(d)		(39.75	)%		2.53	%(e)(f)		7.29	%(e)		11.84	%(e)		19.26	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		2.10	%(h)		1.92	%		1.85	%		1.93	%		2.00	%		2.23	%
Net investment loss (g)		(1.24	)%(h)		(1.24	)%		(0.87	)%		(1.01	)%		(0.72	)%		(1.80	)%
Waiver/Reimbursement		—			—			0.01	%		0.02	%		0.01	%		0.02	%
Portfolio turnover rate		16	%(d)		23	%		21	%		13	%		13	%		18	%
Net assets at end of period (000s)	$	21,287		$	23,633		$	53,820		$	65,040		$	73,168		$	72,643

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.09 per share.

(d) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

Class C Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	14.89		$	25.77		$	26.81		$	25.59		$	24.14		$	20.36
Income from Investment Operations
Net investment loss (a)		(0.09	)		(0.30	)		(0.30	)(b)		(0.30	)		(0.20	)		(0.39	)
Net realized and unrealized gain/(loss)		1.21			(9.62	)		0.97			2.13			3.02			4.31
Total from Investment Operations		1.12			(9.92	)		0.67			1.83			2.82			3.92
Less Distributions to Shareholders
From net realized gains		—			(0.96	)		(1.71	)		(0.61	)		(1.37	)		(0.14	)
Net Asset Value, End of Period	$	16.01		$	14.89		$	25.77		$	26.81		$	25.59		$	24.14
Total Return (c)		7.52	%(d)		(39.87	)%		2.39	%(e)(f)		7.14	%(e)		11.76	%(e)		19.26	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		2.18	%(h)		2.08	%		2.03	%		2.05	%		2.10	%		2.23	%
Net investment loss (g)		(1.32	)%(h)		(1.39	)%		(1.07	)%		(1.14	)%		(0.81	)%		(1.80	)%
Waiver/Reimbursement		—			—			0.00	%(i)		0.01	%		0.01	%		0.02	%
Portfolio turnover rate		16	%(d)		23	%		21	%		13	%		13	%		18	%
Net assets at end of period (000s)	$	25,641		$	25,899		$	50,743		$	55,306		$	42,844		$	39,643

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.09 per share.

(e) Not annualized.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

(i) Rounds to less than 0.01%.

See accompanying notes to financial statements.

Columbia Acorn International Select

Class A Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	17.99		$	31.74		$	27.68		$	20.36		$	17.85		$	14.45
Income from Investment Operations
Net investment income/(loss) (a)		0.10			0.20			0.04	(b)		0.03			0.06			(0.00	)(c)
Net realized and unrealized gain/(loss)		1.58			(13.41	)		5.91			7.29			2.69			3.43
Total from Investment Operations		1.68			(13.21	)		5.95			7.32			2.75			3.43
Less Distributions to Shareholders
From net investment income		(0.15	)		—			(0.12	)		—			(0.24	)		(0.03	)
From net realized gains		—			(0.54	)		(1.77	)		—			—			—
Total Distributions to Shareholders		(0.15	)		(0.54	)		(1.89	)		—			(0.24	)		(0.03	)
Redemption Fees
Redemption fees added to paid in capital (a)(c)		0.00			0.00			0.00			0.00			0.00			0.00
Net Asset Value, End of Period	$	19.52		$	17.99		$	31.74		$	27.68		$	20.36		$	17.85
Total Return (d)		9.33	%(e)		(42.30	)%		21.50	%(f)		35.97	%(f)		15.60	%(f)		23.76	%(f)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		1.57	%(h)		1.54	%		1.49	%		1.58	%		1.70	%		1.75	%
Net investment income/(loss) (g)		1.14	%(h)		0.78	%		0.11	%		0.11	%		0.34	%		(0.03	)%
Waiver/Reimbursement		—			—			0.00	%(i)		0.02	%		0.10	%		0.37	%
Portfolio turnover rate		36	%(e)		68	%		57	%		47	%		39	%		73	%
Net assets at end of period (000s)	$	60,654		$	46,522		$	48,538		$	22,599		$	10,219		$	4,357

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.07 per share.

(d) Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deffered sales charge.

(e) Not annualized.

(f) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

(i) Rounds to less than 0.01%.

Class B Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	17.16		$	30.50		$	26.73		$	19.80		$	17.36		$	14.12
Income from Investment Operations
Net investment income/(loss) (a)		0.04			0.04			(0.13	)(b)		(0.12	)		(0.03	)		(0.10	)
Net realized and unrealized gain/(loss)		1.51			(12.84	)		5.67			7.05			2.61			3.34
Total from Investment Operations		1.55			(12.80	)		5.54			6.93			2.58			3.24
Less Distributions to Shareholders
From net investment income		—			—			—			—			(0.14	)		—
From net realized gains		—			(0.54	)		(1.77	)		—			—			—
Total Distributions to Shareholders		—			(0.54	)		(1.77	)		—			(0.14	)		—
Redemption Fees
Redemption fees added to paid in capital (a)(c)		0.00			0.00			0.00			0.00			0.00			0.00
Net Asset Value, End of Period	$	18.71		$	17.16		$	30.50		$	26.73		$	19.80		$	17.36
Total Return (d)		9.03	%(e)(f)		(42.68	)%		20.69	%(f)		35.00	%(f)		14.97	%(f)		22.95	%(f)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		2.20	%(h)		2.17	%		2.10	%		2.25	%		2.30	%		2.38	%
Net investment gain/(loss) (g)		0.52	%(h)		0.16	%		(0.45	)%		(0.53	)%		(0.16	)%		(0.66	)%
Waiver/Reimbursement		0.24	%(h)		—			0.01	%		0.04	%		0.28	%		0.58	%
Portfolio turnover rate		36	%(e)		68	%		57	%		47	%		39	%		73	%
Net assets at end of period (000s)	$	3,691		$	4,444		$	11,941		$	9,787		$	6,594		$	5,097

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.07 per share.

(d) Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(e) Not annualized.

(f) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

Class C Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	17.08		$	30.42		$	26.70		$	19.80		$	17.38		$	14.14
Income from Investment Operations
Net investment gain/(loss) (a)		0.02			0.00	(b)		(0.20	)(c)		(0.15	)		(0.05	)		(0.11	)
Net realized and unrealized gain/(loss)		1.52			(12.80	)		5.69			7.05			2.60			3.35
Total from Investment Operations		1.54			(12.80	)		5.49			6.90			2.55			3.24
Less Distributions to Shareholders
From net investment income		—			—			—			—			(0.13	)		—
From net realized gains		—			(0.54	)		(1.77	)		—			—			—
Total Distributions to Shareholders		—			(0.54	)		(1.77	)		—			(0.13	)		—
Redemption Fees
Redemption fees added to paid in capital (a)(b)		0.00			0.00			0.00			0.00			0.00			0.00
Net Asset Value, End of Period	$	18.62		$	17.08		$	30.42		$	26.70		$	19.80		$	17.38
Total Return (d)		9.02	%(e)		(42.79	)%		20.53	%(f)		34.85	%(f)		14.77	%(f)		22.91	%(f)
Ratios to Average Net Assets/Supplemental Data
Net expenses (g)		2.45	%(h)		2.34	%		2.29	%		2.38	%		2.45	%		2.45	%
Net investment gain/(loss) (g)		0.28	%(h)		0.01	%		(0.68	)%		(0.67	)%		(0.30	)%		(0.73	)%
Waiver/Reimbursement		—			—			0.01	%		0.02	%		0.17	%		0.35	%
Portfolio turnover rate		36	%(e)		68	%		57	%		47	%		39	%		73	%
Net assets at end of period (000s)	$	9,562		$	9,747		$	13,023		$	7,060		$	4,083		$	2,543

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Rounds to less than $0.01 per share.

(c) Net investment income per share includes special dividends. The effect of these dividends amounted to $0.07 per share.

(d) Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(e) Not annualized.

(f) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(h) Annualized.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn Select

Class A Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	13.77		$	27.89		$	26.18		$	22.47		$	20.83		$	18.01
Income from Investment Operations
Net investment loss (a)		(0.06	)		(0.18	)		(0.15	)		(0.13	)		(0.09	)		(0.16	)
Net realized and unrealized gain/(loss)		3.38			(13.25	)		2.50			4.45			2.32			3.42
Total from Investment Operations		3.32			(13.43	)		2.35			4.32			2.23			3.26
Less Distributions to Shareholders
From net investment income		—			—			—			(0.02	)		—			—
From net realized gains		—			(0.69	)		(0.64	)		(0.59	)		(0.59	)		(0.44	)
Total Distributions to Shareholders		—			(0.69	)		(0.64	)		(0.61	)		(0.59	)		(0.44	)
Net Asset Value, End of Period	$	17.09		$	13.77		$	27.89		$	26.18		$	22.47		$	20.83
Total Return (b)		24.11	%(c)		(49.31	)%(d)		8.92	%(e)		19.32	%(e)		10.78	%(e)		18.16	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		1.39	%(g)		1.24	%		1.19	%		1.24	%		1.26	%		1.47	%
Net investment loss (f)		(0.84	)%(g)		(0.80	)%		(0.52	)%		(0.54	)%		(0.42	)%		(0.86	)%
Waiver/Reimbursement		—			—			0.00	%(h)		0.03	%		0.03	%		0.02	%
Portfolio turnover rate		9	%(c)		28	%		14	%		21	%		19	%		34	%
Net assets at end of period (000s)	$	423,925		$	395,794		$	1,117,941		$	940,857		$	744,178		$	515,842

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deffered sales charge.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g) Annualized.

(h) Rounds to less than 0.01%.

Class B Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	13.02		$	26.57		$	25.13		$	21.71		$	20.23		$	17.64
Income from Investment Operations
Net investment loss (a)		(0.10	)		(0.31	)		(0.31	)		(0.28	)		(0.23	)		(0.31	)
Net realized and unrealized gain/(loss)		3.18			(12.55	)		2.39			4.29			2.24			3.34
Total from Investment Operations		3.08			(12.86	)		2.08			4.01			2.01			3.03
Less Distributions to Shareholders
From net realized gains		—			(0.69	)		(0.64	)		(0.59	)		(0.53	)		(0.44	)
Net Asset Value, End of Period	$	16.10		$	13.02		$	26.57		$	25.13		$	21.71		$	20.23
Total Return (b)		23.66	%(c)(d)		(49.62	)%(e)		8.22	%(d)		18.54	%(d)		10.01	%(d)		17.24	%(d)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		2.10	%(g)		1.87	%		1.79	%		1.91	%		1.99	%		2.26	%
Net investment loss (f)		(1.54	)%(g)		(1.43	)%		(1.12	)%		(1.21	)%		(1.15	)%		(1.65	)%
Waiver/Reimbursement		0.03	%(g)		—			0.01	%		0.03	%		0.03	%		0.02	%
Portfolio turnover rate		9	%(c)		28	%		14	%		21	%		19	%		34	%
Net assets at end of period (000s)	$	76,156		$	73,152		$	199,182		$	214,260		$	206,441		$	185,545

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(d) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g) Annualized.

Class C Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	12.94		$	26.46		$	25.07		$	21.69		$	20.23		$	17.64
Income from Investment Operations
Net investment loss (a)		(0.11	)		(0.34	)		(0.36	)		(0.31	)		(0.25	)		(0.30	)
Net realized and unrealized gain/(loss)		3.17			(12.49	)		2.39			4.28			2.24			3.33
Total from Investment Operations		3.06			(12.83	)		2.03			3.97			1.99			3.03
Less Distributions to Shareholders
From net realized gains		—			(0.69	)		(0.64	)		(0.59	)		(0.53	)		(0.44	)
Net Asset Value, End of Period	$	16.00		$	12.94		$	26.46		$	25.07		$	21.69		$	20.23
Total Return (b)		23.65	%(c)		(49.71	)%(d)		8.04	%(e)		18.37	%(e)		9.91	%(e)		17.24	%(e)
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		2.23	%(g)		2.04	%		1.98	%		2.04	%		2.08	%		2.25	%
Net investment loss (f)		(1.67	)%(g)		(1.60	)%		(1.31	)%		(1.34	)%		(1.24	)%		(1.64	)%
Waiver/Reimbursement		—			—			0.00	%(h)		0.03	%		0.03	%		0.02	%
Portfolio turnover rate		9	%(c)		28	%		14	%		21	%		19	%		34	%
Net assets at end of period (000s)	$	74,894		$	70,962		$	197,100		$	173,152		$	149,160		$	110,435

(a) Per share data was calculated using the average shares outstanding during the period.

(b) Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(e) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(f) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

(g) Annualized.

(h) Rounds to less than 0.01%.

See accompanying notes to financial statements.

Columbia Thermostat Fund

Class A Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	8.26		$	12.31		$	12.59		$	12.49		$	13.11		$	12.30
Income from Investment Operations
Net investment income (a)		0.04			0.22			0.49			0.45			0.39			0.28
Net realized and unrealized gain/(loss)		0.58			(3.98	)		0.53			0.84			0.29			0.81
Total from Investment Operations		0.62			(3.76	)		1.02			1.29			0.68			1.09
Less Distributions to Shareholders
From net investment income		0.00	(b)		(0.22	)		(0.51	)		(0.47	)		(0.39	)		(0.25	)
From net realized gains		—			(0.07	)		(0.79	)		(0.72	)		(0.91	)		(0.03	)
Total Distributions to Shareholders		0.00	(b)		(0.29	)		(1.30	)		(1.19	)		(1.30	)		(0.28	)
Net Asset Value, End of Period	$	8.88		$	8.26		$	12.31		$	12.59		$	12.49		$	13.11
Total Return (c)(d)		7.52	%(e)		(30.67	)%		8.19	%		10.56	%		5.25	%		8.92	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (f)		0.50	%(g)		0.50	%(h)		0.50	%(h)		0.50	%(h)		0.50	%(h)		0.50	%(h)
Net investment income		1.03	%(g)		1.99	%(h)		3.75	%(h)		3.53	%(h)		2.97	%(h)		2.23	%(h)
Waiver/Reimbursement		0.36	%(g)		0.18	%		0.18	%		0.20	%		0.15	%		0.33	%
Portfolio turnover rate		1	%(e)		130	%		128	%		66	%		96	%		67	%
Net assets at end of period (000s)	$	38,497		$	41,032		$	53,246		$	58,013		$	71,034		$	77,092

(b) Rounds to less than $(0.01) per share.

(c) Total return at net asset value assuming all distributions reinvested and no initial sales charge or contingent deferred sales charge.

(d) Had the Advisor not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e) Not annualized.

(f) Does not include expenses of the investment companies in which the Fund invests.

(g) Annualized.

(h) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

Class B Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	8.32		$	12.38		$	12.62		$	12.51		$	13.14		$	12.32
Income from Investment Operations
Net investment income (a)		0.02			0.16			0.42			0.38			0.31			0.19
Net realized and unrealized gain/(loss)		0.59			(4.00	)		0.54			0.84			0.28			0.83
Total from Investment Operations		0.61			(3.84	)		0.96			1.22			0.59			1.02
Less Distributions to Shareholders
From net investment income		—			(0.15	)		(0.41	)		(0.39	)		(0.31	)		(0.17	)
From net realized gains		—			(0.07	)		(0.79	)		(0.72	)		(0.91	)		(0.03	)
Total Distributions to Shareholders		—			(0.22	)		(1.20	)		(1.11	)		(1.22	)		(0.20	)
Net Asset Value, End of Period	$	8.93		$	8.32		$	12.38		$	12.62		$	12.51		$	13.14
Total Return (b)(c)		7.33	%(d)		(31.10	)%		7.71	%		9.91	%		4.56	%		8.27	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (e)		1.00	%(f)		1.00	%(g)		1.00	%(g)		1.06	%(g)		1.10	%(g)		1.18	%(g)
Net investment income		0.52	%(f)		1.45	%(g)		3.25	%(g)		2.99	%(g)		2.39	%(g)		1.55	%(g)
Waiver/Reimbursement		0.42	%(f)		0.20	%		0.19	%		0.23	%		0.19	%		0.29	%
Portfolio turnover rate		1	%(d)		130	%		128	%		66	%		96	%		67	%
Net assets at end of period (000s)	$	32,245		$	36,673		$	67,709		$	72,367		$	78,444		$	78,040

(b) Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(c) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(d) Not annualized.

(e) Does not include expenses of the investment companies in which the Fund invests.

(f) Annualized.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

Class C Shares	(Unaudited) Six Months ended June 30,			Year ended December 31,
_{Selected data for a share outstanding throughout each period}	2009			2008			2007			2006			2005			2004
Net Asset Value, Beginning of Period	$	8.33		$	12.37		$	12.62		$	12.51		$	13.13		$	12.32
Income from Investment Operations
Net investment income (a)		0.01			0.13			0.39			0.36			0.29			0.19
Net realized and unrealized gain/(loss)		0.58			(3.97	)		0.53			0.84			0.29			0.81
Total from Investment Operations		0.59			(3.84	)		0.92			1.20			0.58			1.00
Less Distributions to Shareholders
From net investment income		—			(0.13	)		(0.38	)		(0.37	)		(0.29	)		(0.16	)
From net realized gains		—			(0.07	)		(0.79	)		(0.72	)		(0.91	)		(0.03	)
Total Distributions to Shareholders		—			(0.20	)		(1.17	)		(1.09	)		(1.20	)		(0.19	)
Net Asset Value, End of Period	$	8.92		$	8.33		$	12.37		$	12.62		$	12.51		$	13.13
Total Return (b)(c)		7.08	%(d)		(31.20	)%		7.36	%		9.72	%		4.49	%		8.13	%
Ratios to Average Net Assets/Supplemental Data
Net expenses (e)		1.25	%(f)		1.25	%(g)		1.25	%(g)		1.25	%(g)		1.25	%(g)		1.25	%(g)
Net investment income		0.21	%(f)		1.23	%(g)		3.02	%(g)		2.81	%(g)		2.21	%(g)		1.48	%(g)
Waiver/Reimbursement		0.40	%(f)		0.20	%		0.19	%		0.23	%		0.19	%		0.26	%
Portfolio turnover rate		1	%(d)		130	%		128	%		66	%		96	%		67	%
Net assets at end of period (000s)	$	19,523		$	24,383		$	26,908		$	27,375		$	28,316		$	31,161

(b) Total return at net asset value assuming all distributions reinvested and no contingent deferred sales charge.

(c) Had the Advisor and/or Transfer Agent not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(d) Not annualized.

(e) Does not include expenses of the investment companies in which the Fund invests.

(f) Annualized.

(g) The benefits derived from custody fees paid indirectly had an impact of less than 0.01%.

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited)

1. Nature of Operations

Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat Fund (the "Funds") are each a series of Columbia Acorn Trust (the "Trust"), an open-end management investment company organized as a Massachusetts business trust. The investment objective of each Fund is to seek long-term capital appreciation. Columbia Thermostat Fund pursues its investment objective by investing in shares of other mutual funds. As a "fund of funds" under normal circumstances, the Fund allocates at least 95% of its net assets among a selected group of stock and bond mutual funds ("portfolio funds") according to the current level of the Standard & Poor's 500 Index in relation to predetermined ranges set by the Adviser. The Fund may invest up to 5% of its net assets plus any cash received that day in cash, repurchase agreements, high quality short-term paper and government securities.

Class B shares are subject to a CDSC if redeemed within six years of purchase. Class B shares will convert to Class A shares automatically eight years after purchase.

Class C shares are offered at net asset value but are subject to a CDSC on redemptions made within one year after purchase.

Columbia Acorn International and Columbia Acorn International Select impose a 2% redemption fee on shares that are redeemed within 60 days or less of purchase. See the discussion of Fund policies regarding redemption fees in the Funds' prospectuses for more information.

The financial highlights for the Fund's Class Z shares are presented in a separate semiannual report.

2. Significant Accounting Policies

>Security valuation

established by the Board of Trustees. The Funds have retained an independent statistical fair value pricing service that employs a systematic methodology to assist in the fair valuation process for securities principally traded in a foreign market in order to adjust for possible changes in value that may occur between the close of the foreign exchange and the time as of which the securities are to be valued. If a security is valued at fair value, that value may be different from the last quoted market price for the security.

• Level 1 – quoted prices in active markets for identical securities

• Level 2 – other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk and others)

• Level 3 – significant unobservable inputs (including management's own assumptions in determining the value of investments)

The inputs or methodologies used for valuing securities are not necessarily an indication of the risk associated with investing in those securities.

In April 2009, the Financial Accounting Standards Board ("FASB") issued FASB Staff Position 157-4, Determining Fair Value When the Value and Level of Activity for the Asset or Liability Have Significantly Decreased and Identifying Transactions That Are Not Orderly ("FSP FAS 157-4"), which amends SFAS 157 and is effective for interim and annual periods ending after June 15, 2009. FSP FAS 157-4 provides additional guidance for estimating fair value in accordance with SFAS 157, when the volume and level of activity for the asset or liability measured at fair value has significantly decreased. Additionally, FSP FAS 157-4 expands disclosure req uirements for reporting entities with respect to categories of assets and liabilities carried at fair value. Management does not expect the adoption of FSP FAS 157-4 to have a material impact on the Funds' financial statement disclosure.

>Repurchase agreements

Each Fund may engage in repurchase agreement transactions. Each Fund, through its custodian, receives delivery of underlying securities collateralizing repurchase agreements. The counterparty is required to maintain collateral that is at all times at least equal to the repurchase price including interest. In the event of default or bankruptcy by the counterparty to the agreement, realization and/or retention of the collateral may be subject to legal proceedings.

>Foreign currency translations

>Forward foreign currency exchange contracts

A forward foreign currency exchange contract would limit the risk of loss due to a decline in the value of a particular

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited), continued

On January 1, 2009, the Fund adopted Statement of Financial Accounting Standards No. 161, Disclosures about Derivative Instruments and Hedging Activities – an amendment of FASB Statement No. 133 ("SFAS 161"). SFAS 161 requires additional discussion about the reporting entity's derivative instruments and hedging activities, by providing for qualitative disclosures about the objectives and strategies for using derivatives, quantitative data about the fair value of and gains and losses on derivative contracts, and details of credit-risk-related contingent features in their derivative contracts. For additional information on derivative instruments, please see Note 5.

>Securities lending

Each Fund may lend securities up to one-third of the value of its total assets to certain approved brokers, dealers and other financial institutions to earn additional income. In lending its securities, the Fund retains the benefits of owning the securities, including receipt of dividends or interest generated by the security. The Fund also receives a fee for the loan. The Fund has the ability to recall the loans at any time and could do so in order to vote proxies or to sell the loaned securities. Each loan is collateralized by cash that exceeds the value of the securities on loan. The market value of the loaned securities is determined daily at the close of business of the Fund and any additional required collateral is delivered to the Fund on the next business day. The Fund has elected to invest the cash collateral in the Dreyfus Government Cash Management Fund, and the income earned is paid to the Fund, net of any fees remit ted to Goldman Sachs Agency Lending as the lending agent and net of any borrower rebates. The Funds' advisor, Columbia Wanger Asset Management, L.P. ("CWAM") does not retain any fees earned by the lending program nor does it charge the Funds for administering the program. Generally, in the event of borrower default, the Fund has the right to use the collateral to offset any losses incurred. In the event the Fund is delayed or prevented from exercising its right to dispose of the collateral, there may be a potential loss to the Fund. Some of these losses may be indemnified by the lending agent. The Fund bears the risk of loss with respect to the investment of collateral.

>Security transactions and investment income

>Restricted securities

>Use of estimates

>Fund share valuation

>Custody fees/credits

Custody fees are reduced based on each Fund's cash balances maintained with the custodian. The amount is disclosed as a reduction of total expenses on the Statements of Operations.

>Federal income taxes

>Foreign capital gains taxes

>Distributions to Shareholders

Distributions to shareholders are recorded on the ex-dividend date.

>Indemnification

3. Federal Tax Information

The tax character of distributions paid during the year ended December 31, 2008 were as follows:

	Ordinary Income*		Long-Term Capital Gains
(in thousands)
Columbia Acorn Fund	$	24,585	$	412,506
Columbia Acorn International		32,574		74,297
Columbia Acorn USA		9		53,514
Columbia Acorn International Select		601		4,740
Columbia Acorn Select		—		74,125
Columbia Thermostat Fund		3,595		824

*For tax purposes short-term capital gain distributions, if any, are considered ordinary income distributions.

	Year of Expiration
	2009			2010			2011		2012- 2015		2016		Total
(in thousands)
Columbia Acorn Fund	$	—		$	—		$	—	$	—	$	—	$	—
Columbia Acorn International		—			—			—		—		135,487		135,487
Columbia Acorn USA		1,012	*		506	*		—		—		76,008		77,526
Columbia Acorn International Select		—			—			—		—		30,442		30,442
Columbia Acorn Select		—			—			—		—		12,271		12,271
Columbia Thermostat Fund		—			—			—		—		5,193		5,193

Under Financial Accounting Standards Board Interpretation No. 48, Accounting for Uncertainty in Income Taxes – an Interpretation of FASB Statement No. 109 ("FIN 48")

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited), continued

management determines whether a tax position of a Fund is more likely than not to be sustained upon examination by the applicable taxing authority, including resolution of any related appeals or litigation processes, based on the technical merits of the position. The tax benefit to be recognized is measured as the largest amount of benefit that is greater than fifty percent likely of being realized upon ultimate settlement. Management has evaluated the known implications of FIN 48 on its computation of net assets for the Funds. As a result of this evaluation, management believes that FIN 48 does not have any effect on the Fund's financial statements. However, management's conclusions regarding FIN 48 may be subject to review and adjustment at a later date based on factors including, but not limited to, further implementation guidance from FASB, new tax laws, regulations, and administrative interpretations (including relevant cou rt decisions). Each Fund's federal tax returns for the prior three fiscal years remain subject to examination by the Internal Revenue Service. The Funds are not aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months.

4. Transactions with Affiliates

Columbia Acorn Fund

Average Daily Net Assets	Annual Fee Rate
Up to $700 million		0.74	%
$700 million to $2 billion		0.69	%
$2 billion to $6 billion		0.64	%
$6 billion and over		0.63	%

Columbia Acorn International

Average Daily Net Assets	Annual Fee Rate
Up to $100 million		1.19	%
$100 million to $500 million		0.94	%
$500 million and over		0.74	%

Columbia Acorn USA

Average Daily Net Assets	Annual Fee Rate
Up to $200 million		0.94	%
$200 million to $500 million		0.89	%
$500 million to $2 billion		0.84	%
$2 billion to $3 billion		0.80	%
$3 billion and over		0.70	%

Columbia Acorn International Select

Average Daily Net Assets	Annual Fee Rate
Up to $500 million		0.94	%
$500 million and over		0.90	%

Columbia Acorn Select

Average Daily Net Assets	Annual Fee Rate
Up to $700 million		0.85	%
$700 million to $2 billion		0.80	%
$2 billion to $3 billion		0.75	%
$3 billion and over		0.70	%

Columbia Thermostat Fund

				Annual Fee Rate
All Average Daily Net Assets					0.10	%

For the six months ended June 30, 2009, the Funds' annualized effective investment advisory fee rates were as follows:

Columbia Acorn Fund	0.65	%
Columbia Acorn International	0.78	%
Columbia Acorn USA	0.88	%
Columbia Acorn International Select	0.94	%
Columbia Acorn Select	0.83	%
Columbia Thermostat Fund	0.10	%

>Expense Limit

CWAM has voluntarily agreed to reimburse the ordinary operating expenses (exclusive of distribution and service fees, brokerage commissions, interest, taxes and extraordinary expenses, but inclusive of custodian charges relating to overdrafts, if any) after giving effect to any balance credits from the Funds' custodian, exceeding 1.45% annually of the average daily net assets for Columbia Acorn International Select and 1.35% annually of the average daily net assets for Columbia Acorn Select. These arrangements may be modified or terminated by either the Funds or CWAM on 30 days notice.

CWAM has contractually agreed to waive fees and/or reimburse expenses of Columbia Thermostat Fund so that the ordinary operating expenses (exclusive of distribution and service fees, interest and fees on borrowings, and expenses associated with the Fund's investment in other investment

companies, but including custodian charges relating to overdrafts, if any), after giving effect to any balance credits from the Fund's custodian, will not exceed 0.25% annually of the Fund's average daily net assets through April 30, 2010. There is no guarantee that this arrangement will continue thereafter.

Expenses reimbursed by CWAM to Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat Fund for the six months ended June 30, 2009, were $4,468, $8,850 and $203,763, respectively.

CWAM provides administrative services and receives an administration fee from the Funds at the following annual rates:

Columbia Acorn Trust

Aggregate Average Daily Net Assets of the Trust:	Annual Fee Rate
Up to $8 billion		0.050	%
$8 billion to $16 billion		0.040	%
$16 billion to $35 billion		0.030	%
$35 billion to $45 billion		0.025	%
$45 billion and over		0.015	%

Columbia Management Distributors, Inc. ("CMDI"), a wholly owned subsidiary of BOA, is the Funds' principal underwriter.

For the six months ended June 30, 2009, Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select and Columbia Thermostat Fund have been advised that CMDI retained $136,167 in underwriting discounts in connection with redemptions of Class A shares and received CDSCs of $1,647, $343,567 and $29,954, in connection with Class A, Class B and Class C share redemptions, respectively.

Certain officers and trustees of the Trust are also officers of CWAM. The Trust makes no direct payments to its officers and trustees who are affiliated with CWAM.

An affiliated person of the Fund may include any company in which a Fund owns five percent or more of its outstanding voting shares. On June 30, 2009, Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA and Columbia Acorn Select each held five percent or more of the outstanding voting securities of one or more companies. Details of investments in those affiliated companies are presented on pages 35, 36, 45, 56 and 68, respectively.

Columbia Acorn Family of Funds

Notes to Financial Statements (Unaudited), continued

5. Derivative Instruments

Derivatives not accounted for as hedging instruments under Statement 133:

Fair Value of Derivative Instruments for Columbia Acorn International as of June 30, 2009

	Asset			Liability
	Statement of Assets and Liabilities	Fair Value		Statement of Assets and Liabilities	Fair Value
(in thousands)
Forward foreign currency exchange contracts	Unrealized appreciation on forward foreign currency exchange contracts	$	3,212	Unrealized depreciation on forward foreign currency exchange contracts	$	5,646
Total		$	3,212		$	5,646

Columbia Acorn International

Amount of Realized Gain or (Loss) on Derivatives Recognized in Income on the Statement of Operations for the Six Months Ended June 30, 2009

	Forward Foreign Currency Exchange Contracts			Total
(in thousands)
Net realized gain (loss) on foreign currency transactions and forward foreign currency exchange contracts	$	(2,562	)	$	(2,562	)

Change in Unrealized Appreciation or (Depreciation) on Derivatives Recognized in Income on the Statement of Operations for the Six Months Ended June 30, 2009

	Forward Foreign Currency Exchange Contracts		Total
(in thousands)
Net change in unrealized appreciation (depreciation) on foreign currency translations and forward foreign currency exchange contracts	$	845	$	845

6. Borrowing Arrangements

7. Investment Transactions

The aggregate cost of purchases and proceeds from sales, other than short-term obligations, for the six months ended June 30, 2009, were:

Columbia Acorn Fund

(in thousands)
Investment securities
Purchases	$	1,470,748
Proceeds from sales		1,690,503

Columbia Acorn International

(in thousands)
Investment securities
Purchases	$	527,086
Proceeds from sales		660,319

Columbia Acorn USA

(in thousands)
Investment securities
Purchases	$	215,919
Proceeds from sales		148,557

Columbia Acorn International Select

(in thousands)
Investment securities
Purchases	$	143,633
Proceeds from sales		89,068

Columbia Acorn Select

(in thousands)
Investment securities
Purchases	$	119,281
Proceeds from sales		272,525

Columbia Thermostat Fund

(in thousands)
Investment securities
Purchases	$	831
Proceeds from sales		20,724

8. Redemption Fees

9. Legal Proceedings

The Trust and CWAM are also defendants in a class action lawsuit that alleges, in summary, that the Trust and CWAM exposed shareholders of Columbia Acorn International Fund to trading by market timers by allegedly: (a) failing to properly evaluate daily whether a significant event affecting the value of the Fund's securities had occurred after foreign markets had closed but before the calculation of the Fund's net asset value ("NAV"); (b) failing to implement the Fund's portfolio valuation and share pricing policies and procedures; and (c) failing to know and implement applicable rules and regulations concerning the calculation of NAV (the "Fair Valuation Lawsuit"). The Seventh Circuit ruled that the plaintiffs' state law claims were preempted under federal law resulting in the dismissal of plaintiffs' complaint. Plaintiffs appealed the Seventh Circuit's ruling to the United States Supreme Court. The Supreme Court reversed the S eventh Circuit's ruling on jurisdictional grounds and the case was ultimately remanded to the state court.

Columbia Acorn Trust and CWAM intend to defend these suits vigorously.

CWAM believes that the lawsuits are not likely to materially affect its ability to provide investment management services to the Funds.

[Excerpt from:]

Columbia Acorn Trust

Management Fee Evaluation of the Senior Officer

Prepared Pursuant to the New York Attorney General's
Assurance of Discontinuance

May 2009

Introduction

According to the Order, the Senior Officer's evaluation must consider at least the following:

(1) Management fees (including components thereof) charged to institutional and other clients of CWAM for like services;

(2) Management fees (including any components thereof) charged by other mutual fund companies for like services;

(3) Costs to CWAM and its affiliates of supplying services pursuant to the management fee agreements, excluding any intra-corporate profit;

(4) Profit margins of CWAM and its affiliates from supplying such services;

(5) Possible economies of scale as the Funds grow larger; and

(6) The nature and quality of CWAM's services, including the performance of each Fund.

2008 Evaluation

Process and Independence

The Fee Reductions Mandated under the Order

Conclusions

My review of the data and other material above leads to the following conclusions with respect to the factors identified in the Order.

a. Capacity. CWAM has maintained its investment management capacity even in a difficult environment.

b. Compliance. CWAM has a reasonably designed compliance program that protects shareholders.

Recommendations

I believe the Trustees should:

1. Monitor closely the performance of Acorn Select and Acorn USA to ensure that appropriate steps are being taken by CWAM to improve their relative performance.

Robert P. Scales

May 26, 2009

Board Approval of the Advisory Agreement

Board Approval of the Advisory Agreement, continued

Columbia Acorn Family of Funds

Second Quarter Class A, B and C Share Information

Minimum Initial Investment in all Funds				$2,500 $1,000 for an IRA
Minimum Subsequent Investment in all Funds				$50
Exchange Fee				None

Columbia Acorn Fund	Class A			Class B*			Class C
Management Fees		0.65	%		0.65	%		0.65	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.22	%		0.40	%		0.29	%
Net Expense Ratio		1.12	%		1.80	%		1.94	%
Columbia Acorn International	Class A			Class B*			Class C
Management Fees		0.78	%		0.78	%		0.78	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.42	%		0.64	%		0.49	%
Net Expense Ratio		1.45	%		2.17	%		2.27	%
Columbia Acorn USA	Class A			Class B*			Class C
Management Fees		0.88	%		0.88	%		0.88	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.23	%		0.47	%		0.30	%
Net Expense Ratio		1.36	%		2.10	%		2.18	%
Columbia Acorn International Select	Class A			Class B*			Class C
Management Fees		0.94	%		0.94	%		0.94	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.38	%		0.51	%		0.51	%
Net Expense Ratio		1.57	%		2.20	%		2.45	%
Columbia Acorn Select	Class A			Class B*			Class C
Management Fees		0.83	%		0.83	%		0.83	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses		0.31	%		0.52	%		0.40	%
Net Expense Ratio		1.39	%		2.10	%		2.23	%
Columbia Thermostat Fund	Class A			Class B*			Class C
Management Fees		0.10	%		0.10	%		0.10	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%
Other Expenses**		0.15	%		0.15	%		0.15	%
Net Expense Ratio		0.50	%		1.00	%		1.25	%

Fees and expenses are for the six months ended June 30, 2009. Some share classes of Columbia Acorn Select and Columbia Acorn International Select Funds include the effect of CWAM's voluntary undertaking to waive fees and/or reimburse the Funds for any ordinary operating expenses (exclusive of distribution and service fees, brokerage commissions, interest, taxes and extraordinary expenses, but inclusive of custodian charges relating to overdrafts, if any), after giving effect to any balance credits from the Funds' custodian, in excess of the annual rate of 1.35% and 1.45%, respectively, of the average daily net assets. These arrangements may be modified or terminated by either the Funds or CWAM upon 30 days notice. Columbia Thermostat Fund's fees and expenses include the effect of CWAM's contractual undertaking to waive fees and/or reimburse the Fund for any ordinary operating expenses (exclusive of distri bution and service fees, interest and fees on borrowings, and expenses associated with the Fund's investment in other investment companies, but including custodian charges relating to overdrafts, if any), after giving effect to any balance credits from the Fund's custodian, in excess of the annual rate of 0.25% of the average daily net assets. Columbia Thermostat Fund's reimbursement arrangement is contractual through April 30, 2010. There is no guarantee that this arrangement will continue thereafter.

* The Funds no longer offer Class B shares (other than through dividend reinvestment).

** Does not include estimated fees and expenses of 0.78% incurred by the Fund from the underlying portfolio funds in which it invests.

Columbia Acorn Family of Funds

Trustees

Robert E. Nason

Chairman of the Board*

Allan B. Muchin

Vice Chairman of the Board

Laura M. Born

Michelle L. Collins

Maureen M. Culhane

Margaret M. Eisen

Jerome Kahn, Jr.

Steven N. Kaplan

David C. Kleinman

Charles P. McQuaid

James A. Star

Ralph Wanger

John A. Wing

Officers

Charles P. McQuaid

President

Ben Andrews

Vice President

Michael G. Clarke

Assistant Treasurer

Jeffrey R. Coleman

Assistant Treasurer

P. Zachary Egan

Vice President

Peter T. Fariel

Assistant Secretary

John M. Kunka

Assistant Treasurer

Joseph C. LaPalm

Vice President

Bruce H. Lauer

Vice President, Secretary and Treasurer

Louis J. Mendes III

Vice President

Robert A. Mohn

Vice President

Christopher J. Olson

Vice President

Robert P. Scales

Chief Compliance Officer, Chief Legal Officer,
Senior Vice President and General Counsel

Linda K. Roth-Wiszowaty

Assistant Secretary

* Deceased, June 27, 2009.

Investment Advisor

Columbia Wanger Asset Management, L.P.
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606

1-800-922-6769

Distributor

Columbia Management Distributors, Inc.
One Financial Center
Boston, Massachusetts 02111-2621

Transfer Agent, Dividend Disbursing Agent

Columbia Management Services, Inc.
P. O. Box 8081
Boston, Massachusetts 02266-8081

1-800-345-6611

Legal Counsel to the Funds

K&L Gates LLP
Washington, DC

Legal Counsel to the Independent Trustees

Drinker Biddle & Reath LLP
Philadelphia, Pennsylvania

Independent Registered Public Accounting Firm

PricewaterhouseCoopers LLP
Chicago, Illinois

This report, including the schedules of investments, is submitted for the general information of the shareholders of Columbia Acorn Trust.

Columbia Management Group, LLC ("Columbia Management") is the investment management division of Bank of America Corporation. Columbia Management entities furnish investment management services and products for institutional and individual investors. Columbia Funds are distributed by Columbia Management Distributors, Inc., member of FINRA, SIPC, part of Columbia Management and an affiliate of Bank of America Corporation.

Columbia Wanger Asset Management, L.P. ("CWAM") is a registered investment advisor and an indirect, wholly owned subsidiary of Bank of America Corporation. CWAM is part of Columbia Management.

Find out what's new – visit our web site at:

www.columbiafunds.com

Our e-mail address is:

ServiceInquiries@ColumbiaManagement.com

Columbia Management^®

Columbia Acorn Family of Funds

Class A, B and C Shares

Semiannual Report, June 30, 2009

For More Information

You'll find more information about the Columbia Acorn Family Funds in the documents described below. Contact Columbia Funds as follows to obtain these documents free of charge:

By Mail: Columbia Funds
c/o Columbia Management Services, Inc.
P.O. Box 8081
Boston, MA 02266-8081

By Telephone: 800.345.6611

Online: www.columbiafunds.com

Shareholder Communications with the Board

Prospectuses and the Statement of Additional Information (SAI)

Information Provided by the SEC

The investment company registration number of Columbia Acorn Trust, of which each of these Funds are a series, is 811-01829.

One Financial Center, Boston, MA 02111-2621

800.345.6611 www.columbiamanagement.com

SHC-44/20002-0609 09/87790

Item 2. Code of Ethics.

Not applicable for semi-annual reports.

Item 3. Audit Committee Financial Expert.

Not applicable for semi-annual reports.

Item 4. Principal Accountant Fees and Services.

Not applicable for semi-annual reports.

Item 5. Audit Committee of Listed Registrants.

Not applicable.

Item 6. Investments

(a) The registrant’s “Schedule I — Investments in securities of unaffiliated issuers” (as set forth in 17 CFR 210.12-12) is included in Item 1 of this Form N-CSR.

(b) Not applicable.

Item 7. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies.

Not applicable.

Item 8. Portfolio Managers of Closed-End Management Investment Companies.

Not applicable.

Item 9. Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers.

Not applicable.

Item 10. Submission of Matters to a Vote of Security Holders.

There have not been any material changes to the procedures by which shareholders may recommend nominees to the registrant’s board of directors, since those procedures were last disclosed in response to requirements of Item 407(c)(2)(iv) of Regulation S-K (as required by Item 22(b)(15) of Schedule 14A) or this Item.

Item 11. Controls and Procedures.

(a) The registrant’s principal executive officer and principal financial officers, based on their evaluation of the registrant’s disclosure controls and procedures as of a date within 90 days of the filing of this report, have concluded that such controls and procedures are adequately designed to ensure that information required to be disclosed by the registrant in Form N-CSR is accumulated and communicated to the registrant’s management, including the principal executive officer and principal financial officer, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure.

(b) There was no change in the registrant’s internal control over financial reporting that occurred during the registrant’s second fiscal quarter of the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting.

Item 12. Exhibits.

(a)(1) Code of ethics required to be disclosed under Item 2 of Form N-CSR: Not applicable at this time.

(a)(2) Certifications pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) attached hereto as Exhibit 99.CERT.

(a)(3) Not applicable.

(b) Certification pursuant to Rule 30a-2(b) under the Investment Company Act of 1940 (17 CFR 270.30a-2(b)) attached hereto as Exhibit 99.906CERT.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

(registrant)			Columbia Acorn Trust


By (Signature and Title)			/s/ Charles P. McQuaid
			Charles P. McQuaid, President


Date			August 21, 2009

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By (Signature and Title)			/s/ Charles P. McQuaid
			Charles P. McQuaid, President


Date			August 21, 2009


By (Signature and Title)			/s/ Bruce H. Lauer
			Bruce H. Lauer, Treasurer


Date			August 21, 2009

Columbia Thermostat Fund (CTFAX) N-CSRSCertified semi-annual shareholder report (management investment company)