Columbia Thermostat Fund NCSR Certified 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)

227 W. Monroe Street Suite 3000 Chicago, IL					60606
(Address of principal executive offices)					(Zip code)

Scott R. Plummer Columbia Management Investment Advisers, LLC 5228 Ameriprise Financial Center Minneapolis, MN 55474

P. Zachary Egan Columbia Acorn Trust 227 West Monroe Street, Suite 3000 Chicago, Illinois 60606

Mary C. Moynihan Perkins Coie LLP 700 13th Street, NW Suite 600 Washington, DC 20005
(Name and address of agent for service)

Registrant’s telephone number, including area code:				(312) 634-9200

Date of fiscal year end:	December 31

Date of reporting period:		December 31, 2014

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.

Q4 2014

Columbia Acorn Family of Funds

Class A, B, C, I, R, R4, R5, Y and Z Shares

Managed by Columbia Wanger Asset Management, LLC

Annual Report

December 31, 2014

n Columbia
Acorn® Fund

n Columbia
Acorn International®

n Columbia
Acorn USA®

n Columbia
Acorn International Select^SM

n Columbia
Acorn Select^SM

n Columbia
Thermostat Fund^SM

n Columbia
Acorn Emerging Markets Fund^SM

n Columbia
Acorn European Fund^SM

Not FDIC insured • No bank guarantee • May lose value

Columbia Acorn Family of Funds

Net Asset Value Per Share as of 12/31/14

	Columbia Acorn® Fund		Columbia Acorn International®		Columbia Acorn USA®		Columbia Acorn International Select^SM		Columbia Acorn Select^SM		Columbia Thermostat Fund^SM		Columbia Acorn Emerging Markets Fund^SM		Columbia Acorn European Fund^SM
Class A	$	30.30	$	41.68	$	29.13	$	22.04	$	21.03	$	14.86	$	12.72	$	14.34
Class B	$	26.53	$	40.38	$	25.27	$	20.69	$	18.03	$	14.97		N/A		N/A
Class C	$	25.92	$	40.20	$	24.98	$	20.54	$	17.69	$	14.96	$	12.65	$	14.16
Class I	$	32.03	$	41.76	$	31.19	$	22.29	$	22.38		N/A	$	12.75	$	14.33
Class R		N/A	$	41.67		N/A		N/A		N/A		N/A		N/A		N/A
Class R4	$	32.51	$	42.02	$	31.70	$	22.45	$	22.75	$	14.74	$	12.83	$	14.40
Class R5	$	32.55	$	41.71	$	31.71	$	22.43	$	22.78	$	14.75	$	12.82	$	14.47
Class Y	$	32.61	$	42.02	$	31.80	$	22.42	$	22.86	$	14.74	$	12.71		N/A
Class Z	$	31.95	$	41.73	$	31.03	$	22.30	$	22.28	$	14.67	$	12.74	$	14.34

Class I shares are available only to the Columbia funds, such as Columbia Thermostat Fund, and are not available to individual investors. Class R, R4, R5, Y and Z shares are sold at net asset value and have limited eligibility. Please see the Funds' prospectuses for details. The Columbia Acorn Funds offer multiple share classes, not all necessarily available through all firms, and the share class ratings may vary. Contact us for details.

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's 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.

Acorn®, Acorn USA® and Acorn International® are service marks owned and registered by Columbia Acorn Trust.

A Comment on Trading Volumes

Market conditions are always changing and vary by country and industry sector, and investing in international markets involves unique risks. In the wake of the 2007-2009 financial crisis, trading volumes in both emerging and developed international markets declined significantly and have stayed at generally reduced levels since then. Although it is difficult to accurately assess trends in trading volumes in foreign markets, because some amount of activity has migrated to alternative trading venues, a reduction in trading volumes poses challenges to the Funds. This is particularly so because the Funds focus on small- and mid-cap companies that usually have lower trading volumes and often take sizeable positions in portfolio companies. As a result of lower trading volumes, it may take longer to buy or sell securities, which can exacerbate a Fund's exposure to volatile markets. A Fund may also be limited in its ability to execute favorable trades in portfolio securities in response to changes in company prices and fundamentals. If a Fund is forced to sell securities to meet redemption requests or other cash needs, or in the case of an event affecting liquidity in a particular market or markets, it may be forced to dispose of those securities under disadvantageous circumstances and at a loss. As a Fund grows in size, these considerations take on increasing significance and may adversely impact performance.

Letter to Shareholders from the
Columbia Acorn Trust Board of Trustees

2014 was a difficult year for actively managed equity portfolios. Although the S&P 500, a common measure of performance for domestic securities, rose 13.7% for the year, only 20% of active U.S. equity fund managers outperformed their benchmarks.¹ Commentators offer various theories for this underperformance. Some believe that active managers do best when interest rates are rising, not falling as they have recently. Others argue that "dispersion"—the difference between the best and worst performing stocks—has been low by historical standards, limiting the potential benefits of active management. Finally, few managers anticipated the precipitous drop in the price of oil, and with it the decline in price of the securities of energy related companies.

The domestic Acorn Funds have not been immune to these and other influences. While all the domestic Acorn Funds finished the year in positive territory, they underperformed their benchmarks. The international Acorn Funds faced headwinds too, losing ground for the year and falling short of their benchmarks which turned in negative or uninspiring results for the year. The only benchmark to end in the black was the S&P Emerging Markets Index, which returned 1.19%.

The Board of Trustees monitors the Funds' performance carefully. In the pages that follow, the portfolio managers offer their thoughts and observations about the characteristics and performance of their respective Funds. While remaining faithful to the time-tested investment philosophy of the Acorn Funds, these managers are working hard to reposition the portfolios, where necessary, to seek improved returns. Your Board shares their hope for better results in 2015.

While the portfolio managers continue their efforts to achieve improved performance on your behalf, the Board has been active on other fronts as well. Two new Trustees joined us, Charles Phillips and Thomas Goldstein. They each bring decades of valuable experience and wisdom to the task of overseeing the Acorn Funds and we welcome their contributions. A subject of particular interest to the Board is cyber security. The cyber-attacks on Target, JP Morgan Chase & Co., Sony Corporation and other highly publicized

incidents have prompted many financial services organizations to scrutinize closely their defenses to such attacks. The mutual fund industry, fortunately, has not yet been the victim of a large scale, successful cyber-attack. We cannot assure our shareholders that such an attack will not take place in the future, but as a Board we are doing what we can to identify and monitor cyber-security risks to the Funds.

The Acorn Funds have enjoyed a long and distinguished history of serving shareholders. We thank you for your support and continued confidence in that legacy.

Laura Born
Independent Chair, Board of Trustees,
Columbia Acorn Trust

¹ Barron's, "Return of the Stockpickers" (January 12, 2015)

Columbia Acorn Family of Funds

Table of Contents

Descriptions of Indexes					1
Share Class Performance					2
Fund Performance vs. Benchmarks					3
2014 Year-End Distributions					4
Squirrel Chatter II: Communications Satellites Past and Present					6
Understanding Your Expenses					9
Columbia Acorn® Fund
In a Nutshell					12
At a Glance					13
Major Portfolio Changes (Unaudited)					28
Statement of Investments					31
Columbia Acorn International®
In a Nutshell					14
At a Glance					15
Major Portfolio Changes (Unaudited)					43
Statement of Investments					45
Portfolio Diversification					54
Columbia Acorn USA®
In a Nutshell					16
At a Glance					17
Major Portfolio Changes (Unaudited)					55
Statement of Investments					57
Columbia Acorn International Select^SM
In a Nutshell					18
At a Glance					19
Major Portfolio Changes (Unaudited)					63
Statement of Investments					64
Portfolio Diversification					68

Columbia Acorn Select^SM
In a Nutshell					20
At a Glance					21
Major Portfolio Changes (Unaudited)					69
Statement of Investments					70
Columbia Thermostat Fund^SM
In a Nutshell					22
At a Glance					23
Statement of Investments					75
Columbia Acorn Emerging Markets Fund^SM
In a Nutshell					24
At a Glance					25
Major Portfolio Changes (Unaudited)					77
Statement of Investments					79
Portfolio Diversification					83
Columbia Acorn European Fund^SM
In a Nutshell					26
At a Glance					27
Major Portfolio Changes (Unaudited)					84
Statement of Investments					86
Portfolio Diversification					90
Columbia Acorn Family of Funds^SM
Statements of Assets and Liabilities					92
Statements of Operations					94
Statements of Changes in Net Assets					96
Financial Highlights					102
Notes to Financial Statements					118
Report of Independent Registered Public Accounting Firm					129
Federal Income Tax Information (Unaudited)					130
Board of Trustees and Management					131
Expense Information					137

Columbia Acorn Family of Funds

Descriptions of Indexes Included in this Report

• 50/50 Blended Benchmark, established by the Fund's investment manager, 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 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 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.

• Euromoney Smaller European Companies (inc UK) Index is an index of smaller companies in Europe including the UK market. The Euromoney Smaller European Companies Index covers companies of small- and mid-cap market capitalization in Europe's developed markets. The index is rebalanced on a quarterly basis.

• Lipper Indexes include the largest funds tracked by Lipper, Inc. in the named category. Lipper Mid-Cap Growth Funds Index, 30 largest mid-cap growth funds, including Columbia Acorn Fund; Lipper International Small/Mid Growth Funds Index, 10 largest non-U.S. small/mid growth funds, including Columbia Acorn International; Lipper Small-Cap Growth Funds Index, 30 largest small-cap growth funds, including Columbia Acorn USA; Lipper Mid-Cap Core Funds Index, 30 largest mid-cap core 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; Lipper Emerging Markets Index, 30 largest emerging markets funds; Lipper European Region Index, 10 largest European funds.

• MSCI Europe, Australasia, Far East (EAFE) Index (Net) is a capitalization-weighted index that tracks the total return of common stocks in 22 developed-market countries within Europe, Australasia and the Far East. The returns of the MSCI EAFE Index (Net) are presented net of the withholding tax rate applicable to foreign non-resident institutional investors in the foreign companies included in the index who do not benefit from double taxation treaties.

• MSCI Emerging Markets Small Cap Index (Net), a widely recognized international benchmark, is a free float-adjusted market capitalization index that is designed to measure small-cap emerging market equity performance. The MSCI Emerging Markets Small Cap Index currently consists of the following 23 emerging market country indexes: Brazil, Chile, China, Colombia, Czech Republic, Egypt, Hungary, India, Indonesia, Korea, Malaysia, Mexico, Morocco, Peru, Philippines, Poland, Qatar, Russia, South Africa, Taiwan, Thailand, Turkey and United Arab Emirates.

• Russell 2000 Index measures the performance of the 2,000 smallest companies in the Russell 3000 Index, which represents approximately 10% 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.

• 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 $2B and $10B® 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 Emerging Markets Between $500M and $5B® Index represents the institutionally investable capital of emerging market countries with market caps ranging between $500 million to $5 billion, as selected by S&P. The index currently consists of the following 20 emerging market country indexes: Brazil, Chile, China, Colombia, Czech Republic, Egypt, Hungary, India, Indonesia, Malaysia, Mexico, Morocco, Peru, Philippines, Poland, Russia, South Africa, Taiwan, Thailand and Turkey.

• S&P Europe Between $500M and $5B® Index represents the institutionally investable capital of 17 European countries, as determined by S&P, with market caps ranging between $500 million to $5 billion. The index consists of the following European countries: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.

• S&P Global Ex-U.S. SmallCap® Index consists of the bottom 20% of institutionally investable capital of developed and emerging countries, excluding the United States.

• S&P Global Ex-U.S. Between $500M and $5B® 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.

Columbia Acorn Family of Funds

Share Class Performance Average Annual Total Returns through 12/31/14

	Class A						Class B						Class C						Class I			Class R			Class R4			Class R5			Class Y			Class Z
	Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge			Without Sales Charge			With Sales Charge
Columbia Acorn® Fund
1 year		0.55	%		-5.23	%		-0.16	%		-4.27	%		-0.16	%		-0.98	%		0.91	%		N/A			0.81	%		0.89	%		0.94	%		0.82	%
5 years		13.02	%		11.69	%		12.34	%		12.08	%		12.18	%		12.18	%		13.41	%		N/A			13.33	%		13.37	%		13.39	%		13.35	%
10 years		8.08	%		7.44	%		7.41	%		7.41	%		7.25	%		7.25	%		8.42	%		N/A			8.38	%		8.40	%		8.41	%		8.39	%
Columbia Acorn International®
1 year		-4.58	%		-10.05	%		-5.29	%		-9.75	%		-5.27	%		-6.16	%		-4.20	%		-4.95	%		-4.39	%		-4.25	%		-4.21	%		-4.28	%
5 years		8.11	%		6.84	%		7.36	%		7.06	%		7.31	%		7.31	%		8.54	%		7.76	%		8.43	%		8.48	%		8.50	%		8.47	%
10 years		8.59	%		7.95	%		7.87	%		7.87	%		7.76	%		7.76	%		8.99	%		8.26	%		8.94	%		8.95	%		8.97	%		8.95	%
Columbia Acorn USA®
1 year		3.35	%		-2.58	%		2.37	%		-1.74	%		2.67	%		1.85	%		3.80	%		N/A			3.60	%		3.68	%		3.76	%		3.61	%
5 years		13.57	%		12.23	%		12.75	%		12.50	%		12.76	%		12.76	%		14.00	%		N/A			13.89	%		13.91	%		13.94	%		13.88	%
10 years		7.33	%		6.69	%		6.59	%		6.59	%		6.52	%		6.52	%		7.68	%		N/A			7.63	%		7.64	%		7.65	%		7.62	%
Columbia Acorn International Select^SM
1 year		-7.06	%		-12.39	%		-7.71	%		-11.77	%		-7.80	%		-8.61	%		-6.72	%		N/A			-6.83	%		-6.77	%		-6.71	%		-6.79	%
5 years		7.21	%		5.95	%		6.52	%		6.23	%		6.37	%		6.37	%		7.63	%		N/A			7.55	%		7.58	%		7.60	%		7.57	%
10 years		7.42	%		6.78	%		6.73	%		6.73	%		6.57	%		6.57	%		7.79	%		N/A			7.75	%		7.77	%		7.78	%		7.76	%
Columbia Acorn Select^SM
1 year		2.17	%		-3.70	%		1.35	%		-2.60	%		1.42	%		0.63	%		2.49	%		N/A			2.39	%		2.50	%		2.53	%		2.47	%
5 years		10.28	%		8.98	%		9.54	%		9.30	%		9.45	%		9.45	%		10.69	%		N/A			10.58	%		10.62	%		10.64	%		10.60	%
10 years		7.02	%		6.39	%		6.31	%		6.31	%		6.19	%		6.19	%		7.38	%		N/A			7.32	%		7.34	%		7.35	%		7.33	%
Columbia Thermostat Fund^SM
1 year		5.30	%		-0.75	%		4.83	%		-0.17	%		4.50	%		3.50	%		N/A			N/A			5.61	%		5.62	%		5.68	%		5.57	%
5 years		9.82	%		8.54	%		9.28	%		9.00	%		9.00	%		9.00	%		N/A			N/A			10.09	%		10.11	%		10.14	%		10.09	%
10 years		6.29	%		5.66	%		5.73	%		5.73	%		5.49	%		5.49	%		N/A			N/A			6.55	%		6.56	%		6.57	%		6.55	%
Columbia Acorn Emerging Markets Fund^SM
1 year		-4.28	%		-9.81	%		N/A			N/A			-5.03	%		-5.98	%		-4.01	%		N/A			-4.03	%		-4.02	%		-3.95	%		-4.12	%
Life of Fund		8.00	%		6.12	%		N/A			N/A			7.22	%		7.22	%		8.42	%		N/A			8.38	%		8.39	%		8.40	%		8.29	%
Columbia Acorn European Fund^SM
1 year		-7.77	%		-13.09	%		N/A			N/A			-8.44	%		-9.35	%		-7.49	%		N/A			-7.49	%		-7.54	%		N/A			-7.52	%
Life of Fund		12.10	%		10.15	%		N/A			N/A			11.28	%		11.28	%		12.43	%		N/A			12.41	%		12.39	%		N/A			12.40	%

Returns for Class A shares are shown with and without the maximum initial sales charge of 5.75%. Returns for Class B shares are shown with and without the applicable contingent deferred sales charge (CDSC) of 5.00% in the first year, declining to 1.00% in the sixth year and eliminated thereafter. Returns for Class C shares are shown with and without the maximum CDSC of 1.00% for the first year after purchase. The Funds' other classes are not subject to sales charges and have limited eligibility. Please see the Funds' prospectuses for details. Performance for different share classes will vary based on differences in sales charges and certain fees associated with each class.

All results shown assume reinvestment of distributions during the period. Returns do not reflect the deduction of taxes that a shareholder may pay on Fund distributions or on the redemption of Fund shares. Performance results may reflect the effect of any fee waivers or reimbursements of Fund expenses by the investment manager and/or any of its affiliates. Absent these fee waivers and/or expense reimbursement arrangements, performance results may have been lower. Please see Page 137 of this report for information on contractual fee waiver and expense reimbursement agreements in place on December 31, 2014, for Columbia Thermostat Fund, Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund and voluntary fee waiver and expense reimbursement arrangements in place for Columbia Acorn International, Columbia Acorn International Select and Columbia Acorn Select.

The performance information shown represents past performance and is not a guarantee of future results. The investment return and principal value of your investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance data shown. You may obtain performance information current to the most recent month-end by contacting your financial intermediary, visiting columbiamanagement.com or calling 800.922.6769.

The returns shown include the returns of each Fund's Class Z shares, each Fund's oldest share class, in cases where the inception date of the Fund is earlier than the inception date of the particular share class or where a period shown dates to before the inception date of the share class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit columbiamanagement.com/mutual-funds/appended-performance for more information.

Continued on Page 3.

Fund Performance vs. Benchmarks Class Z Average Annual Total Returns through 12/31/14

Class Z Shares	4th quarter*			1 year			5 years			10 years			Life of Fund
Columbia Acorn® Fund (ACRNX) (6/10/70)		3.88	%		0.82	%		13.35	%		8.39	%		14.59	%
Russell 2500 Index		6.77	%		7.07	%		16.36	%		8.72	%		N/A
S&P 500 Index**		4.93	%		13.69	%		15.45	%		7.67	%		11.05	%
Russell 2000 Index		9.73	%		4.89	%		15.55	%		7.77	%		N/A
Lipper Mid-Cap Growth Funds Index		5.82	%		7.91	%		14.72	%		8.88	%		N/A
Columbia Acorn International® (ACINX) (9/23/92)		-2.60	%		-4.28	%		8.47	%		8.95	%		10.88	%
S&P Global Ex-U.S. Between $500M and $5B Index		-3.48	%		-1.76	%		7.14	%		7.65	%		8.31	%
S&P Global Ex-U.S. SmallCap Index		-3.31	%		-3.11	%		7.41	%		7.27	%		7.76	%
MSCI EAFE Index (Net)		-3.57	%		-4.90	%		5.33	%		4.43	%		5.97	%
Lipper International Small/Mid Growth Funds Index		-2.88	%		-5.65	%		9.55	%		8.27	%		N/A
Columbia Acorn USA® (AUSAX) (9/4/96)		7.73	%		3.61	%		13.88	%		7.62	%		10.81	%
Russell 2000 Index		9.73	%		4.89	%		15.55	%		7.77	%		8.69	%
Lipper Small-Cap Growth Funds Index		7.82	%		1.98	%		15.01	%		7.38	%		7.22	%
Columbia Acorn Int'l Select^SM (ACFFX) (11/23/98)		-8.23	%		-6.79	%		7.57	%		7.76	%		8.79	%
S&P Developed Ex-U.S. Between $2B and $10B Index		-2.45	%		-2.10	%		7.53	%		6.25	%		7.41	%
MSCI EAFE Index (Net)		-3.57	%		-4.90	%		5.33	%		4.43	%		4.15	%
Lipper International Small/Mid Growth Funds Index		-2.88	%		-5.65	%		9.55	%		8.27	%		10.03	%
Columbia Acorn Select^SM (ACTWX) (11/23/98)		2.90	%		2.47	%		10.60	%		7.33	%		10.28	%
S&P MidCap 400 Index		6.35	%		9.77	%		16.54	%		9.71	%		10.61	%
S&P 500 Index**		4.93	%		13.69	%		15.45	%		7.67	%		5.55	%
Lipper Mid-Cap Core Funds Index		5.22	%		8.89	%		14.87	%		8.50	%		9.21	%
Columbia Thermostat Fund^SM (COTZX) (9/25/02)		1.78	%		5.57	%		10.09	%		6.55	%		7.99	%
S&P 500 Index		4.93	%		13.69	%		15.45	%		7.67	%		10.02	%
Barclays U.S. Aggregate Bond Index		1.79	%		5.97	%		4.45	%		4.71	%		4.67	%
Lipper Flexible Portfolio Funds Index		0.26	%		4.31	%		8.80	%		6.11	%		8.03	%
50/50 Blended Benchmark		3.36	%		9.85	%		10.09	%		6.48	%		7.60	%
Columbia Acorn Emerging Markets Fund^SM (CEFZX) (8/19/11)		-2.36	%		-4.12	%		—			—			8.29	%
S&P Emerging Markets Between $500M and $5B Index		-3.32	%		1.90	%		—			—			3.31	%
MSCI Emerging Markets Small Cap Index (Net)		-6.02	%		1.01	%		—			—			1.16	%
Lipper Emerging Markets Index		-5.25	%		-2.66	%		—			—			2.18	%
Columbia Acorn European Fund^SM (CAEZX) (8/19/11)		-0.71	%		-7.52	%		—			—			12.40	%
S&P Europe Between $500M and $5B Index		-1.47	%		-5.35	%		—			—			13.80	%
Euromoney Smaller European Companies (inc UK) Index		-3.42	%		-7.67	%		—			—			11.72	%
Lipper European Region Index		-2.51	%		-6.46	%		—			—			12.10	%

The inception dates for Class A, B and C shares (if offered) are as follows: Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select and Columbia Acorn Select, 10/16/00; Columbia Thermostat Fund, 3/3/03; Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund, 8/19/11. The inception dates for Class I shares are as follows: Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select and Columbia Acorn Select, 9/27/10; Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund, 8/19/11. The inception date for Class R shares for Columbia Acorn International is 8/2/11. The inception date for Class R4, R5 and Y shares (if offered) is as follows: Columbia Acorn Fund, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select, Columbia Thermostat Fund, Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund, 11/8/12, except that Class Y shares of Columbia Acorn Emerging Markets Fund commenced operations on 6/13/13 and Class R4 shares of Columbia Acorn European Fund commenced operations on 6/25/14. The inception date for Class R5 shares of Columbia Acorn International is 8/2/11. The inception date for Class R4 and Y shares of Columbia Acorn International is 11/8/12. The inception date for Class Z shares is as follows: Columbia Acorn Fund, 6/10/70; Columbia Acorn International, 9/23/92; Columbia Acorn USA, 9/4/96; Columbia Acorn International Select and Columbia Acorn Select, 11/23/98; Columbia Thermostat Fund, 9/25/02; Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund, 8/19/11.

*Not annualized

**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.

Please see Page 1 for a description of the indexes listed above.

Columbia Acorn Family of Funds

2014 Year-End Distributions

The following table details the year-end distributions for the Columbia Acorn Funds. For all Funds except Columbia Thermostat Fund, the record date was December 8, 2014, and the ex-dividend and payable date was December 9, 2014. For Columbia Thermostat Fund, the record date was December 19, 2014, and the ex-dividend and payable date was December 22, 2014.

Fund	Short-term Capital Gain		Long-term Capital Gain		Ordinary Income		Reinvestment Price
Columbia Acorn® Fund
Class A		None	$	4.83826		None	$	30.00
Class B		None	$	4.83826		None	$	26.28
Class C		None	$	4.83826		None	$	25.67
Class I		None	$	4.83826		None	$	31.70
Class R4		None	$	4.83826		None	$	32.18
Class R5		None	$	4.83826		None	$	32.22
Class Y		None	$	4.83826		None	$	32.28
Class Z		None	$	4.83826		None	$	31.63
Columbia Acorn International®
Class A		None	$	1.80082	$	0.53711	$	41.74
Class B		None	$	1.80082	$	0.19085	$	40.46
Class C		None	$	1.80082	$	0.19085	$	40.27
Class I		None	$	1.80082	$	0.70556	$	41.81
Class R		None	$	1.80082	$	0.34527	$	41.74
Class R4		None	$	1.80082	$	0.62602	$	42.07
Class R5		None	$	1.80082	$	0.68685	$	41.75
Class Y		None	$	1.80082	$	0.71024	$	42.07
Class Z		None	$	1.80082	$	0.67281	$	41.78
Columbia Acorn USA®
Class A		None	$	5.56080		None	$	28.65
Class B		None	$	5.56080		None	$	24.87
Class C		None	$	5.56080		None	$	24.58
Class I		None	$	5.56080		None	$	30.67
Class R4		None	$	5.56080		None	$	31.18
Class R5		None	$	5.56080		None	$	31.19
Class Y		None	$	5.56080		None	$	31.27
Class Z		None	$	5.56080		None	$	30.52
Columbia Acorn International Select^SM
Class A		None	$	2.78219	$	0.09894	$	22.10
Class B		None	$	2.78219	$	0.00000	$	20.76
Class C		None	$	2.78219	$	0.00000	$	20.61
Class I		None	$	2.78219	$	0.19978	$	22.35
Class R4		None	$	2.78219	$	0.16897	$	22.51
Class R5		None	$	2.78219	$	0.18577	$	22.49
Class Y		None	$	2.78219	$	0.20258	$	22.48
Class Z		None	$	2.78219	$	0.18017	$	22.36

Fund	Short-term Capital Gain		Long-term Capital Gain		Ordinary Income		Reinvestment Price
Columbia Acorn Select^SM
Class A		None	$	3.74246		None	$	20.92
Class B		None	$	3.74246		None	$	17.94
Class C		None	$	3.74246		None	$	17.60
Class I		None	$	3.74246		None	$	22.26
Class R4		None	$	3.74246		None	$	22.62
Class R5		None	$	3.74246		None	$	22.65
Class Y		None	$	3.74246		None	$	22.73
Class Z		None	$	3.74246		None	$	22.15
Columbia Thermostat Fund^SM
Class A	$	0.09300	$	0.05196	$	0.27078	$	14.86
Class B	$	0.09300	$	0.05196	$	0.19612	$	14.97
Class C	$	0.09300	$	0.05196	$	0.15879	$	14.96
Class R4	$	0.09300	$	0.05196	$	0.30811	$	14.74
Class R5	$	0.09300	$	0.05196	$	0.31110	$	14.75
Class Y	$	0.09300	$	0.05196	$	0.31857	$	14.73
Class Z	$	0.09300	$	0.05196	$	0.30961	$	14.67
Columbia Acorn Emerging Markets Fund^SM
Class A		None		None	$	0.06967	$	12.64
Class C		None		None	$	0.00000	$	12.58
Class I		None		None	$	0.11366	$	12.67
Class R4		None		None	$	0.10700	$	12.74
Class R5		None		None	$	0.10966	$	12.73
Class Y		None		None	$	0.11366	$	12.62
Class Z		None		None	$	0.09900	$	12.66
Columbia Acorn European Fund^SM
Class A		None		None	$	0.04887	$	14.47
Class C		None		None	$	0.00000	$	14.30
Class I		None		None	$	0.09354	$	14.46
Class R4		None		None	$	0.08738	$	14.53
Class R5		None		None	$	0.08430	$	14.60
Class Z		None		None	$	0.08738	$	14.47

Squirrel Chatter II: Communications Satellites Past and Present

The Soviet Union launched Sputnik, mankind's first satellite, in October 1957. This 184-pound satellite was a 23-inch sphere with four antennas. It transmitted a "beep beep" signal over ham radio frequencies accessible by many around the globe, and its surface was polished so it was visible as it orbited the Earth.¹ Sputnik was a propaganda tool that woke up the world.

Prior to the launch of Sputnik, satellites had been theorized for a long time. In the 17^th century, Sir Isaac Newton developed his theory of gravitation. In it he stated that a projectile launched at the correct angle at a speed of 17,000 miles per hour would orbit the Earth.² In 1945, science fiction writer Arthur C. Clarke introduced the concept of geostationary orbit: a satellite orbiting above the Earth's equator at an altitude of about 22,200 miles elevation would remain over the same position, appearing stationary to people on Earth. Clarke thought that within 50 years, there could be three equally spaced geostationary satellites communicating to virtually the whole planet.³

The United States launched its first satellite, Explorer 1, in January 1958. This satellite discovered the Van Allen radiation belts around Earth. In December 1958, the United States launched its first communications satellite, SCORE, which broadcast a tape-recorded holiday message from President Eisenhower.⁴

Many experiments and innovations in satellites followed. Perhaps the oddest was Echo-1, which inflated into a 100-foot diameter sphere coated in aluminum, enabling it to reflect radio waves.⁵ This passive communications satellite reflected about one ten-millionth of originating signal sent toward it.⁶

Telstar-1, launched in 1962, provided the first live TV broadcast from space, as well as the first phone conversation transmitted by satellite. Rather than being a passive reflector like Echo-1, Telstar-1 had an active transponder that received, amplified and re-sent signals. It could communicate a total of one black and white TV channel along with 600 telephone conversations.⁷

The first satellites achieved low or medium Earth orbits, far below Arthur C. Clarke's geostationary orbit, and transmitted at low power. As a result, ground antennas

needed to be huge, initially 100 feet wide,⁸ and had to rotate in order to remain pointed at a moving satellite.⁹ Furthermore, such satellites are in view of the ground antennas for short periods of time; a low Earth orbit satellite 500 miles up is in touch for 12 minutes per orbit, while a medium Earth satellite 5,000 miles up is in view for 30 minutes.¹⁰

The first successful geostationary communications satellite, Syncom 3, launched in August 1964¹¹ and was stationed over the Pacific Ocean.¹² As planned, it remained in constant contact with fixed-position Earth stations within its coverage area. Also, since geostationary satellites are rarely in Earth's shadow, it was primarily powered by solar cells.¹³ But with a transmitter output of two watts,¹⁴ large Earth stations were needed to communicate with it. Other geostationary satellites followed shortly thereafter. In July 1969, Intelsat, a leading provider of satellite services worldwide, had three geostationary satellites covering nearly the entire Earth, fulfilling Clarke's concept some 25 years earlier than he had imagined.

Early communications satellites, continuing to transmit just one TV channel each,¹⁵ enabled much of the world to witness milestone events, which in turn drove demand for more communications satellites. Syncom satellites carried the 1964 Tokyo Olympics, while Intelsat allowed much of the world to witness Neil Armstrong walking on the moon.¹⁶ Nearly a billion people worldwide watched the 1972 Summer Olympics held in Munich, Germany.

Additional and more powerful communications satellites were launched shortly thereafter, along with improved and less expensive 16- to 33-foot ground antennas. New businesses were created and existing business models were altered. WESTAR I launched in April 1974 and provided fledgling cable TV programmer Home Box Office the opportunity to broadcast live Muhammad Ali's "Thrilla in Manila" fight in 1975.

When entrepreneur Ted Turner learned that he could broadcast his Atlanta WTCG TV station via satellite everywhere in the country, he signed a million-dollar-a-year contract to do so, and in 1976 reached homes in over 27 states via local cable television (CATV) systems.¹⁷ Turner subsequently launched CNN in 1980, creating the first

24-hour news channel. Numerous other CATV channels followed. Satellites enabled cable TV operators to offer additional content, which eventually ended the dominance of the three major U.S. television networks.

As demand for satellite communications rose, the International Telecommunications Union awarded additional radio bandwidth and orbital slots to industry participants. Current communications satellites have far better circuitry, software and solar power, along with innovations such as spot beams, data compression algorithms and fuel-saving electrical propulsion systems. Rather than being simple "bent pipe" mechanisms receiving and transmitting the same signal, today's satellites enhance signals and allocate bandwidth more efficiently.

New satellites continue to be larger, and are broadcasting at higher power and at higher frequencies. Early "C-band" satellite TV signals were transmitted at 10 to 17 watts, while current "Ku-band" satellite TV signals are transmitted at 100 to 200 watts.¹⁸ Higher power and higher frequencies, coupled with improved electronics, facilitate still smaller and cheaper ground station equipment. Neiman Marcus offered a 20-foot satellite TV dish in 1979 for $36,500,¹⁹ capable of receiving only HBO; today, direct-to-home receivers cost below $100 and can receive hundreds of channels using dishes as small as 18 inches across.²⁰

Satellite technology has extended beyond broadcasting TV signals. The Global Positioning System (GPS) was introduced by the U.S. military in 1978, currently consists of 24 satellites in orbit,²¹ and has been made available for civilian use.²² These satellites transmit precise time signals along with their exact positions. A GPS receiver measures the range from three or four satellites and uses simultaneous equations to calculate its position. Vehicle and handheld GPS navigation systems combine position information with map data, and then provide locations and directions to users. It seems that the smallest satellite receivers may currently be GPS wristwatches!

Internet connection for fixed locations in densely populated areas is dominated by cable, telephone and cell phone service providers. Satellite data cannot compete economically with these technologies, where they are available. However, satellites provide data and Internet access elsewhere, in remote areas, on the oceans and in airplanes. These applications have also benefited from

improved satellite technology. For example, satellite data speeds have hit 30 megabits per second per aircraft, up 70-fold from prior generation satellite equipment.²³

The next generation high-throughput satellites, utilizing even higher power and more frequencies, and providing more spot beams, are launching through 2017. Combined, these satellites will increase bandwidth in the sky by a factor of eight to ten,²⁴ and promise to deliver more data, more quickly, to ever more users.

As much as satellite technology has changed the world, investments in satellite companies have had mixed results. We at Columbia Acorn Funds tended to shy away from start-up satellite companies that needed to make large up-front investments before earning highly uncertain revenues. That bias proved correct long ago when satellite phone provider Iridium filed for bankruptcy shortly after launch, citing initial subscriber counts dramatically lower than expected.

Instead, we opted to invest either downstream from satellite technology or in proven satellite service providers. Long ago, domestic Acorn Funds benefited substantially from investments in cable TV channel companies and, more recently, a company providing mapping data. The Funds currently have investments in a company utilizing GPS signals for engineering and construction, and Columbia Acorn Fund owns shares in a satellite service provider that we believe possesses valuable radio spectrum. Other investments include companies utilizing satellite transmitted data to provide Internet connectivity on airplanes. International Acorn Funds have benefited from satellite service providers possessing visible revenue streams within a more consolidated industry.

Charles P. McQuaid

Portfolio Manager, Analyst and Advisor
Columbia Wanger Asset Management, LLC

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 here 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 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 behalf of any particular Columbia Acorn Fund.

¹ Virgil S. Labrador and Peter I. Galace, Heavens Fill with Commerce: A Brief History of the Communications Satellite Industry (Sonoma, California, SATNEWS PUBLISHERS, 2005), p. 23.

² Ibid., p. 15.

³ Ibid., p. 21.

⁴ Ibid., p. 36.

⁵ Ibid., p. 39.

⁶ Steve Ford, The ARRL Satellite Handbook (ARRL, The National Association for Amateur Radio, 2008-2013), appendix B, p. 5.

⁷ Labrador, op. cit., p. 42.

⁸ Bruce Elbert, The Satellite Communication Ground Segment and Earth Station Handbook, Second Edition (Norwood, Massachusetts, Artech House, 2014) p. 10.

⁹ Labrador, op. cit., p. 43.

¹⁰ Elbert, op. cit., p. 77.

¹¹ Labrador, op. cit., p. 46.

¹² NASA Technical Report, R-252, Syncom Engineering Report, Volume II, By Syncom Projects Office, Goddard Space Flight Center, Greenbelt, Maryland, April 1967, p. 3.

¹³ Ibid., p. 10.

¹⁴ Ibid., p. 8.

¹⁵ Labrador, op. cit., p. 115.

¹⁶ Ibid., p. 58.

¹⁷ Ibid., p. 119.

¹⁸ Ibid., p. 133.

¹⁹ Ray B. Browne and Pat Browne, The Guide to United States Popular Culture (Madison, Wisconsin, Popular Press 3, 2001), p. 706.

²⁰ Elbert, op. cit., p. 304.

²¹ Madhavendra Richharia, Mobile Satellite Communications: Principles and Trends, Second Edition (West Sussex, United Kingdom, John Wiley & Sons, Ltd, 2014), p. 30.

²² Ford, op. cit., p. 5-14.

²³ First Edition, The Anatomy of Inflight Connectivity: An Inside Look at What it Takes to Bring Connectivity to Aircraft Around the World (Gogo LLC, an aero-communications service provider, 2014) p. 41.

²⁴ Anne Wainscott-Sargent, "Ground Players Tackle Bandwidth Optimization in an HTS World," Via Satellite, January 2015, p. 16.

Understanding Your Expenses

As a shareholder, you incur two types of costs. There are transaction costs, which generally include sales charges on purchases and may include redemption fees. There are also ongoing costs, which generally include management fees, distribution and service (Rule 12b-1) fees, and other Fund expenses. The following information is intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to help you 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 Class A, B, C, I, R, R4, R5, Y and Z shares of the Funds during the period. The actual and hypothetical information in the tables is based on an initial investment of $1,000 at the beginning of the period indicated and held for the entire period. Expense information is calculated two ways and each method provides you with different information. The amount listed in the "Actual" column is calculated using the Funds' actual operating expenses and total return for the period. You may use the Actual information, together with the amount invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the results by the expenses paid during the period under the Actual column. The amount listed in the "Hypothetical" column assumes a 5% annual rate of return before expenses (which is not the Funds' actual return) and then applies the Funds' 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 period. See "Compare With Other Funds" below for details on how to use the hypothetical data.

In addition to the ongoing expenses which the Funds bear directly, Columbia Thermostat Fund's shareholders indirectly bear the Fund's allocable share of the costs and expenses of each underlying fund in which the Fund invests. You can also estimate the effective expenses paid during the period, which includes the indirect fees associated with investing in the underlying funds, by using the amounts listed in the effective expenses paid during the period column in the "Fund of Funds" table.

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 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 ongoing costs of investing in a fund only and do not reflect any transaction costs, such as sales charges, or redemption or exchange fees. Therefore, the hypothetical calculations are useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds. If transaction costs were included in these calculations, your costs would be higher.

July 1, 2014 – December 31, 2014

	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		981.20		1,019.76		5.39		5.50		1.08
Class B		1,000.00		1,000.00		977.40		1,016.18		8.92		9.10		1.79
Class C		1,000.00		1,000.00		977.60		1,016.23		8.87		9.05		1.78
Class I		1,000.00		1,000.00		982.90		1,021.63		3.55		3.62		0.71
Class R4		1,000.00		1,000.00		982.30		1,020.87		4.30		4.38		0.86
Class R5		1,000.00		1,000.00		982.90		1,021.37		3.80		3.87		0.76
Class Y		1,000.00		1,000.00		982.90		1,021.68		3.50		3.57		0.70
Class Z		1,000.00		1,000.00		982.30		1,021.22		3.95		4.02		0.79

Understanding Your Expenses, continued

	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 International®
Class A		1,000.00		1,000.00		901.60		1,019.00		5.90		6.26		1.23
Class B		1,000.00		1,000.00		898.20		1,015.17		9.52		10.11		1.99
Class C		1,000.00		1,000.00		898.40		1,015.27		9.43		10.01		1.97
Class I		1,000.00		1,000.00		903.50		1,020.92		4.08		4.33		0.85
Class R		1,000.00		1,000.00		899.80		1,016.99		7.81		8.29		1.63
Class R4		1,000.00		1,000.00		902.60		1,019.96		4.99		5.30		1.04
Class R5		1,000.00		1,000.00		903.20		1,020.62		4.37		4.63		0.91
Class Y		1,000.00		1,000.00		903.40		1,020.87		4.13		4.38		0.86
Class Z		1,000.00		1,000.00		903.00		1,020.47		4.51		4.79		0.94
Columbia Acorn USA®
Class A		1,000.00		1,000.00		1,007.60		1,018.45		6.78		6.82		1.34
Class B		1,000.00		1,000.00		1,002.60		1,013.51		11.71		11.77		2.32
Class C		1,000.00		1,000.00		1,004.30		1,015.12		10.10		10.16		2.00
Class I		1,000.00		1,000.00		1,009.70		1,020.77		4.46		4.48		0.88
Class R4		1,000.00		1,000.00		1,008.70		1,019.71		5.52		5.55		1.09
Class R5		1,000.00		1,000.00		1,009.00		1,020.21		5.01		5.04		0.99
Class Y		1,000.00		1,000.00		1,009.60		1,020.47		4.76		4.79		0.94
Class Z		1,000.00		1,000.00		1,008.90		1,019.76		5.47		5.50		1.08
Columbia Acorn International Select^SM
Class A		1,000.00		1,000.00		848.30		1,017.80		6.85		7.48		1.47
Class B		1,000.00		1,000.00		844.90		1,014.42		9.95		10.87		2.14
Class C		1,000.00		1,000.00		844.70		1,013.91		10.42		11.37		2.24
Class I		1,000.00		1,000.00		849.50		1,019.56		5.22		5.70		1.12
Class R4		1,000.00		1,000.00		849.30		1,019.16		5.59		6.11		1.20
Class R5		1,000.00		1,000.00		849.40		1,019.41		5.36		5.85		1.15
Class Y		1,000.00		1,000.00		849.70		1,019.66		5.13		5.60		1.10
Class Z		1,000.00		1,000.00		849.50		1,019.26		5.50		6.01		1.18
Columbia Acorn Select^SM
Class A		1,000.00		1,000.00		1,009.50		1,018.55		6.69		6.72		1.32
Class B		1,000.00		1,000.00		1,005.10		1,014.62		10.61		10.66		2.10
Class C		1,000.00		1,000.00		1,005.70		1,014.92		10.31		10.36		2.04
Class I		1,000.00		1,000.00		1,010.90		1,020.47		4.76		4.79		0.94
Class R4		1,000.00		1,000.00		1,010.40		1,019.66		5.57		5.60		1.10
Class R5		1,000.00		1,000.00		1,011.20		1,020.16		5.07		5.09		1.00
Class Y		1,000.00		1,000.00		1,011.20		1,020.42		4.82		4.84		0.95
Class Z		1,000.00		1,000.00		1,011.00		1,020.01		5.22		5.24		1.03

	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 Emerging Markets Fund^SM
Class A		1,000.00		1,000.00		926.80		1,017.39		7.53		7.88		1.55
Class C		1,000.00		1,000.00		923.40		1,013.51		11.25		11.77		2.32
Class I		1,000.00		1,000.00		928.20		1,019.00		5.98		6.26		1.23
Class R4		1,000.00		1,000.00		928.10		1,018.75		6.22		6.51		1.28
Class R5		1,000.00		1,000.00		928.20		1,018.90		6.08		6.36		1.25
Class Y		1,000.00		1,000.00		928.60		1,019.11		5.88		6.16		1.21
Class Z		1,000.00		1,000.00		927.70		1,018.55		6.41		6.72		1.32
Columbia Acorn European Fund^SM
Class A		1,000.00		1,000.00		901.50		1,016.38		8.39		8.89		1.75
Class C		1,000.00		1,000.00		897.90		1,012.60		11.96		12.68		2.50
Class I		1,000.00		1,000.00		903.10		1,017.80		7.05		7.48		1.47
Class R4		1,000.00		1,000.00		903.20		1,017.64		7.20		7.63		1.50
Class R5		1,000.00		1,000.00		902.80		1,017.54		7.29		7.73		1.52
Class Z		1,000.00		1,000.00		902.80		1,017.64		7.19		7.63		1.50

Fund of Funds—Columbia Thermostat Fund

July 1, 2014 – December 31, 2014

	Account value at the beginning of the period ($)				Account value at the end of the period ($)				Expenses paid during the period ($)				Fund's annualized expense ratio (%)		Effective expenses paid during the period ($)				Fund's effective annualized expense ratio (%)
	Actual		Hypothetical		Actual		Hypothetical		Actual		Hypothetical		Actual		Actual		Hypothetical		Actual
Columbia Thermostat Fund^SM
Class A		1,000.00		1,000.00		1,013.70		1,022.68		2.54		2.55		0.50		5.18		5.20		1.02
Class B		1,000.00		1,000.00		1,011.30		1,020.16		5.07		5.09		1.00		7.71		7.74		1.52
Class C		1,000.00		1,000.00		1,009.50		1,018.90		6.33		6.36		1.25		8.97		9.01		1.77
Class R4		1,000.00		1,000.00		1,014.90		1,023.95		1.27		1.28		0.25		3.91		3.93		0.77
Class R5		1,000.00		1,000.00		1,014.40		1,024.05		1.17		1.17		0.23		3.81		3.83		0.75
Class Y		1,000.00		1,000.00		1,014.90		1,024.30		0.91		0.92		0.18		3.56		3.57		0.70
Class Z		1,000.00		1,000.00		1,014.40		1,024.05		1.17		1.17		0.23		3.81		3.83		0.75

Expenses paid during the period are equal to the 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.

Except with respect to Columbia Thermostat Fund, expenses do not include any fees and expenses incurred indirectly by a Fund from the underlying funds in which the Fund may invest (also referred to as "acquired funds"), including affiliated and non-affiliated pooled investments vehicles (including mutual funds and exchange traded funds).

In the case of Columbia Thermostat Fund, effective expenses paid during the period and the Fund's effective annualized expense ratio include expenses borne directly by the class plus the Fund's pro rata portion of the ongoing expenses charged by the underlying funds in which it invests using the expense ratio of each class of each underlying fund as of the underlying fund's most recent shareholder report.

Had the investment manager and/or certain of its affiliates not waived/reimbursed certain fees and expenses for Columbia Acorn International, Columbia Acorn Select, Columbia Thermostat Fund and Columbia Acorn European Fund, account value at the end of the period would have been reduced.

Columbia Acorn® Fund

In a Nutshell


Robert A. Mohn Lead Portfolio Manager				David L. Frank Co-Portfolio Manager

Performance data shown represents past performance and is not a guarantee of future results. The investment return and principal value will fluctuate so that shares, when redeemed, may be worth more or less than the original cost. Current performance may be lower or higher than the performance data shown. Please visit columbiamanagement.com for daily and most recent month-end performance updates.

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, operational and settlement risks and other risks associated with future political and economic developments.

Columbia Acorn Fund Class Z shares gained 3.88% in the fourth quarter of 2014, while the Fund's primary benchmark, the Russell 2500 Index, rose 6.77%. For the annual period ended December 31, 2014, the Fund was up 0.82% versus a 7.07% gain for the benchmark. The performance for both periods was impacted by declines in the international portion of the Fund. International stocks in the portfolio fell 17.43% in 2014, while domestic returns were up 2.91%. We have been consciously decreasing the Fund's exposure to international stocks, ending the year with a 4.2% weight in foreign names, down three percentage points from the Fund's weighting at the end of 2013. We anticipate international exposure within the Fund will continue to be reduced going forward.

While energy price declines were a positive for some Fund holdings, they were a negative for many others. The drop in oil prices from $100 to $50 a barrel damaged the Fund's direct energy names, as well as several industrial companies exposed to energy end markets. Our direct energy investments averaged 5.6% of Fund assets for the year, matching the weight of the energy sector in the benchmark. Oil and gas producers Rosetta Resources and SM Energy saw their stocks drop more than 50% for both the quarter and annual period. Chart Industries and Chicago Bridge & Iron both have business tied to liquefied natural gas manufacturing plant construction. Their stocks fell 64% and 49%, respectively, for the year with Chart Industries falling 44% in the fourth quarter and Chicago Bridge & Iron dropping 27%.

For the annual period, losses in several Fund retail stocks were also a drag on performance. Down 43%, home furnishings retailer Pier 1 Imports suffered from weakening same-store sales. We exited this stock in the fourth quarter. Groupon, an online global marketplace for deals, fell 29% for the annual period as its transition away from a deal-of-the-day email blaster significantly increased operating costs. GNC Holdings, a specialty retailer for health and wellness products, ended the year down 19%, as sales disappointed.

Top contributors for the year and the fourth quarter fell largely into two groups. The first was biotech and biotech-related stocks. Synageva BioPharma, a biotech focused on orphan diseases, initiated a new trial for a drug to treat a rare neurological disease called Sanfilippo syndrome. Its stock rose 35% in the fourth quarter and ended the year up 44%. Cepheid, a molecular diagnostics company, saw its installed base of automated genetic testing instruments grow 47% year-over-year. Its stock gained 23% in the fourth quarter and was up 16% for the year. Laboratory equipment manufacturer Mettler-Toledo International's sales growth reached a two-year high, driving fourth quarter gains of 18% and an annual return of 25%.

The second winning group was comprised of companies aided by the drop in energy prices. HEICO, a manufacturer of aircraft replacement parts, benefited as lower oil prices made older aircraft more competitive. HEICO rose 18% in the fourth quarter and ended the year up 13%. Casey's General Stores, an owner/operator of convenience stores and gas stations, benefited from lower gasoline prices, which boosted its fuel margins. For the quarter, its stock gained 26% and rose 30% for the year.

Outside of these groups, the Fund's largest contributor to performance for the year was car rental company Avis Budget Group. Benefiting from improved volume and pricing, its stock gained 21% in the fourth quarter and ended the year up over 63%. tw telecom, a provider of fiber optic telephone and data services, was acquired by Level 3 Communications and left the Fund with a 31% gain for the year.

Due to our high quality, growth strategy and long-term horizon, Columbia Acorn Fund has historically underweighted utilities and most types of REITs, which together constitute about 15% of the Russell 2500 Index. Both sectors offer high dividend yields but their shares face structural impediments to compounding consistently at high rates of return, either from regulation or an inability to retain capital. Unfortunately, our positioning has generally hurt performance in the past few years since dividend paying stocks like these have become popular as bond substitutes in a very low interest rate environment. Going forward, however, we believe that rates cannot move much lower and will likely increase, eliminating the "search for yield" headwind we faced in 2014. We are not deviating from our growth-at-a-reasonable-price philosophy of owning well-managed companies with unique products and a long runway for expansion.

Fund's Positions in Mentioned Holdings

As a percentage of net assets, as of 12/31/14

Mettler-Toledo International	2.2	%
Cepheid	1.8
Avis Budget Group	1.5
Synageva BioPharma	1.4
HEICO	1.1
Casey's General Stores	0.6
Chicago Bridge & Iron	0.3
Rosetta Resources	0.3
Chart Industries	0.2
SM Energy	0.2
GNC Holdings	0.1
Groupon	0.1

Fund holdings are as of the date given, are subject to change at any time, and are not recommendations to buy or sell any security. Top holdings exclude short-term holdings and cash, if applicable.

Columbia Acorn® Fund

At a Glance

Total Net Assets of the Fund:
$15.9 billion

Performance data shown in the table and graph below represent past performance, do not guarantee future results, assume reinvestment of dividends and distributions and do not reflect the deduction of taxes that a shareholder may pay on Fund distributions or the redemption of Fund shares. The investment return and principal value of an investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance data shown. Performance data reflect fee waivers or reimbursements of Fund expenses, if any; in their absence, performance results would have been lower. Indexes are unmanaged; their results do not reflect the effect of expenses or sales charges. Securities in the Fund may not match those in an index. Please visit columbiamanagement.com for performance data current to the most recent month-end.

The Growth of a $10,000 Investment in Columbia Acorn® Fund Class Z Shares

June 10, 1970 (Fund inception) through December 31, 2014

This chart shows the change in value of a hypothetical $10,000 investment in Class Z shares of the Fund during the stated time period. 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.

Average Annual Total Returns for period ended December 31, 2014

	4th quarter			1 year			5 years			10 years			Life of Fund
Class Z (6/10/70 inception)		3.88	%		0.82	%		13.35	%		8.39	%		14.59	%
Class A (10/16/00 inception)
without sales charge		3.83			0.55			13.02			8.08			14.22
with sales charge		-2.15			-5.23			11.69			7.44			14.07
Russell 2500 Index*		6.77			7.07			16.36			8.72			N/A

Results for other share classes can be found on Page 2.

*The Fund's primary benchmark. Please see Page 1 for index descriptions.

Returns for Class A shown with and without the maximum initial sales charge of 5.75%. As stated in the May 1, 2014, prospectus, the Fund's annual operating expense ratio is 0.79% for Class Z shares and 1.08% for Class A shares. The returns shown for periods prior to the inception of the Fund's Class A shares append the returns of the Fund's Class Z shares, the Fund's oldest share class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit columbiamanagement.com/mutual-funds/ appended-performance for more information.

Portfolio Diversification

as a percentage of net assets, as of 12/31/14

Top 10 Holdings

as a percentage of net assets, as of 12/31/14

1.	Ametek Aerospace/Industrial Instruments	2.4	%
2.	Mettler-Toledo International Laboratory Equipment	2.2	%
3.	Donaldson Industrial Air Filtration	1.9	%
4.	SEI Investments Mutual Fund Administration & Investment Management	1.9	%
5.	Amphenol Electronic Connectors	1.8	%
6.	Cepheid Molecular Diagnostics	1.8	%
7.	Avis Budget Group Car Rental Company	1.5	%
8.	Nordson Dispensing Systems for Adhesives & Coatings	1.5	%
9.	Synageva BioPharma Biotech Focused on Orphan Diseases	1.4	%
10.	Ansys Simulation Software for Engineers & Designers	1.3	%

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.

Columbia Acorn International®

In a Nutshell


P. Zachary Egan Co-Portfolio Manager				Louis J. Mendes III Co-Portfolio Manager

International investing involves special risks, including foreign taxation, currency risks, risks associated with possible differences in financial standards, operational and settlement risks and other risks associated with future political and economic developments. Stocks of small- and mid-cap companies pose special risks, including 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. Please also see "A Comment on Trading Volumes" on the inside front cover of this report.

Columbia Acorn International Class Z shares declined 2.60% in the fourth quarter of 2014, performing better than the Fund's primary benchmark, the S&P Global Ex-U.S. Between $500M and $5B Index, which fell 3.48%. For the full year, the Fund was down 4.28%, lagging the 1.76% decline of the benchmark. For comparison, the large-cap, developed market MSCI EAFE Index (Net) declined 3.57% in the fourth quarter and 4.90% during the year.

After a strong return in 2013, international markets struggled to provide positive U.S. dollar returns due to a number of factors. First and foremost was the strong U.S. dollar against nearly all world currencies. The combination of a recovering U.S. economy and increasing economic and political risk in Eastern Europe and the Middle East sent many investors fleeing to the security of the U.S. dollar. The euro fell over 11% and the British pound fell over 6% to the dollar. In Japan, Abenomics' continued easy money policies helped drive the yen down over 13% versus the dollar. It is not our practice to hedge currency exposures in the Fund in order to express a view on direction. This introduces some volatility to U.S. dollar returns, but we believe it lowers costs in the long term, and also provides shareholders with the benefit of currency diversification when exchange rates move in the other direction.

The second major factor impacting international markets for the year was the rising specter of global deflation, most notably felt in the declining price of most commodities, particularly oil. While oil's dramatic fall in price has triggered debate over whether its cause is U.S.-led supply or declining global growth, there is considerable consensus that slow growth is driving the fall in other commodities, such as iron ore and copper. The flight to safety, as reflected in the roughly 0.85% drop in U.S. Treasury 10-year bond yields, only further reinforces the notion of little inflation in an increasingly hostile world outside the United States. It is notable that the 10-year yield, which has stayed under 2% for most of January 2015, implies a negative real return, assuming the Federal Reserve meets its long-term inflation target of 2%.

For the fourth quarter, top contributions to Fund returns came from a country that is often forgotten in global market discussions: South Africa. This country represented about 2.5% of the Fund's benchmark, but over 5% of Fund assets. Three of the Fund's largest positions—Coronation Fund Managers, Naspers and Rand Merchant Insurance—are based in the country and generated strong returns of 18%, 17% and 14%, respectively, in the quarter. For the full year, these three positions were up 36%, 24% and 38%, respectively, in a market that rose less than 7% in U.S. dollar terms in the benchmark. One factor that these

companies all have in common is excellent management that has allowed them to expand overseas into other markets. Coronation Fund Managers is leveraging off a successful domestic operation to expand into the international fund management business, opening up new avenues of growth. While operating a pay-television franchise in sub-Saharan Africa, Naspers generates the bulk of its value from its investment in Hong Kong-based Tencent, an Internet software/mobile application business. Rand Merchant Insurance is growing through its Australian car insurance operations. Finding overlooked gems in often under-covered markets has been a hallmark of the Acorn style and has yielded strong returns in South Africa.

The quarter's largest detractor in absolute terms was not a particular stock but rather the energy sector in its entirety. Oil prices fell from approximately $100 per barrel to about $50 in the quarter. The ramifications for many small- to mid-sized oil service providers are significant as the major oil companies are expected to cancel many exploration and production projects that no longer make economic sense. The Fund's energy positions on average fell 30% in the fourth quarter and over 38% for the full year.

For the year, Macau casino operator Melco Crown Entertainment fell 35% on negative sentiment, as the industry came under greater scrutiny from mainland China. Neopost, a French provider of postage meter machines, declined 22% during the year on poor contract renewals with the French public sector. While 2014 was a disappointing year, both Melco Crown Entertainment and Neopost have been long-term winners for the Fund's shareholders.

As we look ahead to 2015, international markets remain out of favor as market pundits continue to champion U.S. economic growth and currency strength as a reason for keeping more assets stateside than abroad. While no one knows the future direction of markets, as dedicated international investors, we will continue to seek out the best opportunities we can find for shareholders.

Fund's Positions in Mentioned Holdings

As a percentage of net assets, as of 12/31/14

Coronation Fund Managers	1.8	%
Naspers	1.3
Neopost	1.0
Rand Merchant Insurance	0.9
Melco Crown Entertainment	0.6

Fund holdings are as of the date given, are subject to change at any time, and are not recommendations to buy or sell any security. Top holdings exclude short-term holdings and cash, if applicable.

Columbia Acorn International®

At a Glance

Total Net Assets of the Fund:
$7.7 billion

Performance data shown in the table and graph below represents past performance, does not guarantee future results, assumes reinvestment of dividends and distributions and does not reflect the deduction of taxes that a shareholder may pay on Fund distributions or the redemption of Fund shares. The investment return and principal value of an investment will fluctuate so that shares, when redeemed, may be worth more or less than their original cost. Current performance may be lower or higher than the performance data shown. Performance data reflects fee waivers or reimbursements of Fund expenses, if any; in their absence, performance results would have been lower. Indexes are unmanaged; their results do not reflect the effect of expenses or sales charges. Securities in the Fund may not match those in an index. Please visit columbiamanagement.com for performance data current to the most recent month-end.

The Growth of a $10,000 Investment in Columbia Acorn International® Class Z Shares

September 23, 1992 (Fund inception) through December 31, 2014

This chart shows the change in value of a hypothetical $10,000 investment in Class Z shares of the Fund during the stated time period.

Average Annual Total Returns for period ended December 31, 2014

	4th quarter			1 year			5 years			10 years			Life of Fund
Class Z (9/23/92 inception)		-2.60	%		-4.28	%		8.47	%		8.95	%		10.88	%
Class A (10/16/00 inception)
without sales charge		-2.69			-4.58			8.11			8.59			10.46
with sales charge		-8.28			-10.05			6.84			7.95			10.16
S&P Global Ex-U.S. Between $500M® and $5B*		-3.48			-1.76			7.14			7.65			8.31

Results for other share classes can be found on Page 2.

*The Fund's primary benchmark. Please see Page 1 for index descriptions.

Returns for Class A shown with and without the maximum initial sales charge of 5.75%. As stated in the May 1, 2014, prospectus, the Fund's annual operating expense ratio is 0.94% for Class Z shares and 1.29% for Class A shares. The returns shown for periods prior to the inception of the Fund's Class A shares append the returns of the Fund's Class Z shares, the Fund's oldest share class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit columbiamanagement.com/mutual-funds/
appended-performance for more information.

Portfolio Diversification

as a percentage of net assets, as of 12/31/14

Top 10 Holdings

as a percentage of net assets, as of 12/31/14

1.	Coronation Fund Managers (South Africa) South African Fund Manager	1.8	%
2.	Naspers (South Africa) Media in Africa, China, Russia & other Emerging Markets	1.3	%
3.	CCL Industries (Canada) Global Label Converter	1.2	%
4.	WuXi PharmaTech - ADR (China) Contract Research Organization Business in China	1.1	%
5.	Zee Entertainment Enterprises (India) Programmer of Pay Television Content	1.0	%
6.	Neopost (France) Postage Meter Machines	1.0	%
7.	Partners Group (Switzerland) Private Markets Asset Management	1.0	%
8.	Amcor (Australia) Global Leader in Flexible & Rigid Packaging	1.0	%
9.	Aalberts Industries (Netherlands) Flow Control & Heat Treatment	1.0	%
	10. Wirecard (Germany) Online Payment Processing & Risk Management	0.9	%

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.

Columbia Acorn USA®

In a Nutshell


Robert A. Mohn Lead Portfolio Manager				William J. Doyle Co-Portfolio Manager

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

Columbia Acorn USA Class Z shares ended the fourth quarter up 7.73%. This compares to the 9.73% return for the Fund's primary benchmark, the Russell 2000 Index. For the annual period ended December 31, 2014, the Fund was up 3.61% versus a 4.89% gain for the benchmark. One area that hurt Fund relative performance versus the benchmark, especially for the annual period, was the information technology sector. Our weighting in this group was in line with the benchmark, but our technology stocks failed to keep up with the index's tech stocks. The Fund's performance was also impacted by the dramatic decline in energy prices, which hurt the Fund's energy and energy-related stocks.

The biggest detractors for the annual period in the information technology sector were CalAmp and Ultratech. CalAmp, a provider of machine-to-machine communications systems, was down 35% for the year but rebounded a bit in the fourth quarter, gaining 4%. The company's stock declined on disappointing earnings growth. Ultratech, a manufacturer of semiconductor equipment, ended the year down 39%, as orders for its equipment fell below expectations. We opted to sell this position in the fourth quarter.

Turning to top contributors in the fourth quarter and annual period, car rental company Avis Budget Group continued to provide strong performance through year end. The company has benefited from improved volume and pricing within the industry, and its stock ended the year up 63% and the quarter up 21%. Enjoying strong sales growth and interest from investors looking for a yield substitute in a low-rate environment, self-storage facility owner Extra Space Storage gained 44% in 2014 and 15% in the fourth quarter.

Other winners included several health care-related stocks. Synageva BioPharma, a biotech focused on orphan diseases, initiated a new trial for a drug to treat a rare neurological disease called Sanfilippo syndrome. Its stock rose 35% in the fourth quarter and ended the year up 44%. Cepheid, a molecular diagnostics company, saw its installed base of automated genetic testing instruments grow 47% year-over-year. Its stock gained 23% in the fourth quarter and was up 16% for the year. Laboratory equipment manufacturer Mettler-Toledo International's sales growth reached a two-year high, driving fourth quarter gains of 18% and an annual return of 25%. Akorn, a developer, manufacturer and distributor of specialty generic drugs, doubled its revenues over the prior year, aided by an acquisition and drug price increases. Its stock

was up 48% for the year but cooled in the fourth quarter, gaining just 0.2%.

In addition to the information technology stocks noted above, the other laggards for the year and quarter were not surprisingly energy related. The Fund's average weight in the energy sector was 4.7% of Fund assets in 2014, slightly below the benchmark weight of 5.4%. The drop in oil prices from $100 to $50 a barrel hurt both oil and gas producers, as well as oil service providers. Four of the energy stocks in Columbia Acorn USA had their stock prices fall about 50% in the fourth quarter, roughly in line with the 50% drop in oil in the second half of 2014.

The U.S. economy increasingly appears to be mending itself and moving in a positive direction. U.S. job growth seems relatively healthier than it has been in the recent past. At year end, the S&P 500 Index, a U.S. large-cap stock index, was up 13.69%, while the small-cap Russell 2000 Index lagged behind, rising 4.89% for the year. We believe both small-cap and large-cap stocks should continue to benefit from a strong U.S. economy. We remain optimistic that a growing U.S. economy and accelerating merger and acquisition activity will create a more positive environment for Columbia Acorn USA's small-cap stocks. As growth-at-a-reasonable-price investors, we remain focused on owning well-managed, niche companies that have room to grow.

Fund's Positions in Mentioned Holdings

As a percentage of net assets, as of 12/31/14

Avis Budget Group	3.8	%
Extra Space Storage	3.5
Mettler-Toledo International	3.4
Cepheid	2.2
Synageva BioPharma	2.1
Akorn	1.7
CalAmp	0.4

Fund holdings are as of the date given, are subject to change at any time, and are not recommendations to buy or sell any security. Top holdings exclude short-term holdings and cash, if applicable.

Columbia Acorn USA®

At a Glance

Total Net Assets of the Fund:
$1.3 billion

The Growth of a $10,000 Investment in Columbia Acorn USA® Class Z Shares

September 4, 1996 (Fund inception) through December 31, 2014

This chart shows the change in value of a hypothetical $10,000 investment in Class Z shares of the Fund during the stated time period.

Average Annual Total Returns for period ended December 31, 2014

	4th quarter			1 year			5 years			10 years			Life of Fund
Class Z (9/4/96 inception)		7.73	%		3.61	%		13.88	%		7.62	%		10.81	%
Class A (10/16/00 inception)
without sales charge		7.69			3.35			13.57			7.33			10.44
with sales charge		1.50			-2.58			12.23			6.69			10.08
Russell 2000 Index*		9.73			4.89			15.55			7.77			8.69

Results for other share classes can be found on Page 2.

*The Fund's primary benchmark. Please see Page 1 for index descriptions.

Returns for Class A shown with and without the maximum initial sales charge of 5.75%. As stated in the May 1, 2014, prospectus, the Fund's annual operating expense ratio is 1.07% for Class Z shares and 1.33% for Class A shares. The returns shown for periods prior to the inception of the Fund's Class A shares append the returns of the Fund's Class Z shares, the Fund's oldest share class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit columbiamanagement.com/mutual-funds/
appended-performance for more information.

Portfolio Diversification

as a percentage of net assets, as of 12/31/14

Top 10 Holdings

as a percentage of net assets, as of 12/31/14

1.	Avis Budget Group Car Rental Company	3.8	%
2.	Extra Space Storage Self Storage Facilities	3.5	%
3.	Mettler-Toledo International Laboratory Equipment	3.4	%
4.	Ametek Aerospace/Industrial Instruments	3.0	%
5.	Nordson Dispensing Systems for Adhesives & Coatings	2.9	%
6.	HEICO FAA-approved Aircraft Replacement Parts	2.5	%
7.	Donaldson Industrial Air Filtration	2.4	%
8.	IPG Photonics Fiber Lasers	2.3	%
9.	Cepheid Molecular Diagnostics	2.2	%
10.	Synageva BioPharma Biotech Focused on Orphan Diseases	2.1	%

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.

Columbia Acorn International Select^SM

In a Nutshell


Christopher J. Olson Portfolio Manager

International investing involves special risks, including foreign taxation, currency risks, risks associated with possible differences in financial standards, operational and settlement risks and other risks associated with future political and economic developments. Due to the Fund's concentration in a limited number of stocks, the Fund's portfolio will tend to diverge significantly from benchmark weightings and may therefore pose greater risk and volatility relative to its benchmark, or in comparison to other Columbia Acorn Fund portfolios. Stocks of small- and mid-cap companies pose special risks, including 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. Please also see "A Comment on Trading Volumes" on the inside front cover of this report.

Columbia Acorn International Select Class Z shares ended the fourth quarter of 2014 down 8.23%. This compares to a 2.45% drop in the Fund's primary benchmark, the S&P Developed Ex-U.S. Between $2B and $10B® Index. For the annual period ended December 31, 2014, the Fund was down 6.79% versus a 2.10% decline for its benchmark.

Pummeled by falling oil prices, energy stocks were the biggest detractor from returns for both the quarter and year. The global oil market has been thrown into severe turmoil on concerns about excess supply while, at the same time, demand is weak due to slowing global growth. Canadian oil and gas producer Baytex and U.S.-listed Denbury Resources, an oil producer using Co2 injection, both fell 58% for the year and dropped 56% and 47%, respectively, in the fourth quarter. We opted to sell the Fund's position in Denbury Resources in the quarter.

The Fund's overweight position in materials stocks continued to be a drag on returns. Brazilian gold miner Beadell Resources dropped 49% in the fourth quarter and ended the year down 75%. Falling gold prices and poor weather hampered its mining operations. Tahoe Resources, a silver miner operating in Guatemala, fell 32% in the quarter and 16% for the year as silver prices dropped along with most other commodities and the Guatemalan government doubled its royalty take. Canadian gold miner Goldcorp ended the year down 13% and fell 19% in the fourth quarter, also on a drop in commodity prices.

Up 47%, Canada's CCL Industries, a global label converter, was the top contributor to gains for the year and was also strong in the fourth quarter, gaining 9%. The company made a well-timed and well-priced acquisition that drove strong performance throughout the year. CJ Corp, a holding company of Korean consumer conglomerates, had an annual gain of 27% but cooled in the fourth quarter, falling 15%. The market looked favorably on company moves to lower operating costs to drive up margins, but the stock gave back some of its gains in the fourth quarter. In Japan, auto parts manufacturer NGK Spark Plug ended the annual period up 31% and the fourth quarter up 4%, benefiting from strong earnings growth in 2014 assisted by a weaker yen. Naspers, a provider of media to emerging markets, was the top contributor to gains in the fourth quarter, returning 18%, and ended the year with a 25% return. Chinese Internet company Tencent is Naspers' primary investment and it continued to report robust revenue and earnings gains.

The Fund's overweight position in financials versus its benchmark was a positive for the year and quarter. Coronation Fund Managers, a South African fund manager, ended the year up 34% and gained 18% in the fourth quarter. Coronation's strong fund inflows from retail and

international investors drove continued growth in assets under management and net fees. Ascendas REIT, an industrial property landlord in Singapore, gained 9% in 2014 and finished the fourth quarter up 5% on steady results and the continued search, on the part of investors, for yield. Partners Group, a Swiss private markets asset manager, was up roughly 11% for the quarter and year. The company continued to report robust increases in assets under management.

International equity and currency markets have seen their share of volatility over the past several years, a trend that is likely to continue given uncertain global growth, government intervention and ongoing geopolitical concerns. We, however, remain consistent in our search for strong, underappreciated businesses that can operate successfully in and through such environments.

Fund's Positions in Mentioned Holdings

As a percentage of net assets, as of 12/31/14

Ascendas REIT	5.6	%
CCL Industries	3.3
Tahoe Resources	3.2
NGK Spark Plug	3.2
Partners Group	3.1
Baytex	2.4
Goldcorp	2.2
Naspers	2.1
CJ Corp	2.1
Coronation Fund Managers	1.5
Beadell Resources	0.9

Fund holdings are as of the date given, are subject to change at any time, and are not recommendations to buy or sell any security. Top holdings exclude short-term holdings and cash, if applicable.

Columbia Acorn International Select^SM

At a Glance

Total Net Assets of the Fund:
$252.9 million

The Growth of a $10,000 Investment in Columbia Acorn International Select^SM Class Z Shares

November 23, 1998 (Fund inception) through December 31, 2014

This chart shows the change in value of a hypothetical $10,000 investment in Class Z shares of the Fund during the stated time period.

Average Annual Total Returns for period ended December 31, 2014

	4th quarter			1 year			5 years			10 years			Life of Fund
Class Z (11/23/98 inception)		-8.23	%		-6.79	%		7.57	%		7.76	%		8.79	%
Class A (10/16/00 inception)
without sales charge		-8.27			-7.06			7.21			7.42			8.44
with sales charge		-13.56			-12.39			5.95			6.78			8.04
S&P Developed Ex-U.S. Between $2B and $10B® Index*		-2.45			-2.10			7.53			6.25			7.41

Results for other share classes can be found on Page 2.

*The Fund's primary benchmark. Please see Page 1 for index descriptions.

Returns for Class A shown with and without the maximum initial sales charge of 5.75%. As stated in the May 1, 2014, prospectus, the Fund's annual operating expense ratio is 1.21% for Class Z shares and 1.49% for Class A shares. The returns shown for periods prior to the inception of the Fund's Class A shares append the returns of the Fund's Class Z shares, the Fund's oldest share class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit columbiamanagement.com/mutual-funds/
appended-performance for more information.

Portfolio Diversification

as a percentage of net assets, as of 12/31/14

Top 10 Holdings

as a percentage of net assets, as of 12/31/14

1.	Ascendas REIT (Singapore) Industrial Property Landlord	5.6	%
2.	Singapore Exchange (Singapore) Singapore Equity & Derivatives Market Operator	4.7	%
3.	Challenger Financial (Australia) Annuity Provider in Australia	4.5	%
4.	Babcock International (United Kingdom) Public Sector Outsourcer	3.6	%
5.	CCL Industries (Canada) Global Label Converter	3.3	%
6.	Tahoe Resources (Guatemala) Silver Project in Guatemala	3.2	%
7.	NGK Spark Plug (Japan) Automobile Parts	3.2	%
8.	Swedish Match (Sweden) Swedish Snus	3.1	%
9.	Partners Group (Switzerland) Private Markets Asset Management	3.1	%
10.	KDDI (Japan) Mobile & Fixed Line Communication Service Provider in Japan	3.0	%

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.

Columbia Acorn Select^SM

In a Nutshell


Robert A. Chalupnik Portfolio Manager

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. International investing involves special risks, including foreign taxation, currency risks, risks associated with possible differences in financial standards, operational and settlement risks and other risks associated with future political and economic developments.

Columbia Acorn Select Class Z shares ended the fourth quarter of 2014 up 2.90%, falling short of the 6.35% gain of the Fund's primary benchmark, the S&P MidCap 400 Index. For the annual period ended December 31, 2014, the Fund gained 2.47% versus a 9.77% gain for the benchmark.

Energy holdings were the largest detractor from performance for both periods. Our energy strategy includes holding a basket of small exploration and production companies, many of which have operations outside of the United States in areas that the large-cap energy companies have mostly ignored. Unfortunately, the recent decline in oil prices caused investors to flee this space and the Fund's energy holdings were hit particularly hard. Fund energy stocks and energy-exposed industrial holdings accounted for over half the Fund's underperformance in both the fourth quarter and the year.

Looking at what helped in both the quarter and annual period, Mettler-Toledo International, a manufacturer of laboratory equipment, rose 18% in the quarter and ended the year up 25%. The company enjoyed accelerated growth in both laboratory and industrial products due to market share gains. Management also raised 2014 guidance and provided a solid outlook for 2015. Cepheid, a molecular diagnostics company, saw its installed base of automated genetic testing instruments grow 47% year-over-year. Its stock gained 23% in the fourth quarter and was up 16% for the year. Pall, a provider of life science, water and industrial filtration equipment, was up 21% in the quarter and 20% for the year. Pall enjoyed growth in both its life science and industrial segments. Improved margins have also fueled strong earnings growth.

As noted above, the Fund's underperformers were largely energy names or industrials with significant exposure to the energy sector. The Fund's energy investments averaged 5.6% of Fund assets for the year, in line with the 5.3% energy weight of the benchmark. Canacol, an oil producer in South America, saw its stock drop 55% in the fourth quarter and 68% for the year. Quanta Services provides electrical transmission and pipeline contracting services and is classified as an industrial company. However, nearly 30% of its revenues come from oil and gas pipeline construction projects so its stock fell with energy prices, declining 22% in the fourth quarter and 10% for the year.

During the fourth quarter, we sold out of three stocks and added three new names to the portfolio. Budget hotel brand Choice Hotels was sold when its stock met our price target. We also exited the Fund's positions in oil and gas producers Clayton Williams and Antero Resources to swap into Core Labs, an oil and gas reservoir consulting company. The other two new names are biotech-related companies. VWR is a distributor of lab supplies with leading market share in Europe and a number two market-share position in

the United States. We believe the company should benefit from accelerating spending by well-funded biopharmaceutical companies. Intercept Pharmaceuticals is a biotech firm developing drugs for several diseases. In public clinical trials, its lead drug, OCA, has shown strong efficacy in a liver disease known as NASH, which has no approved treatment.

At the writing of this report, oil prices were just below $50 per barrel versus the $100 mark where they hovered for most of the past five years. Certainly the additional supply of oil from U.S. shale formations is a major contributor to the price decline, but weaker economies in Europe and China are also a factor. Fortunately, the U.S. economy continues to be relatively strong. We remain bullish on the prospects for U.S. mid-cap companies.

Fund's Positions in Mentioned Holdings

As a percentage of net assets, as of 12/31/14

Mettler-Toledo International	3.8	%
Pall	2.7
Cepheid	2.6
Quanta Services	2.2
VWR	1.3
Canacol	0.5
Core Labs	0.5
Intercept Pharmaceuticals	0.4

Fund holdings are as of the date given, are subject to change at any time, and are not recommendations to buy or sell any security. Top holdings exclude short-term holdings and cash, if applicable.

Columbia Acorn Select^SM

At a Glance

Total Net Assets of the Fund:
$666.5 million

The Growth of a $10,000 Investment in Columbia Acorn Select^SM Class Z Shares

November 23, 1998 (Fund inception) through December 31, 2014

This chart shows the change in value of a hypothetical $10,000 investment in Class Z shares of the Fund during the stated time period.

Average Annual Total Returns for period ended December 31, 2014

	4th quarter			1 year			5 years			10 years			Life of Fund
Class Z (11/23/98 inception)		2.90	%		2.47	%		10.60	%		7.33	%		10.28	%
Class A (10/16/00 inception)
without sales charge		2.79			2.17			10.28			7.02			9.93
with sales charge		-3.12			-3.70			8.98			6.39			9.53
S&P MidCap 400® Index*		6.35			9.77			16.54			9.71			10.61

Results for other share classes can be found on Page 2.

*The Fund's primary benchmark. Please see Page 1 for index descriptions.

Returns for Class A shown with and without the maximum initial sales charge of 5.75%. As stated in the May 1, 2014, prospectus, the Fund's annual operating expense ratio is 1.03% for Class Z shares and 1.31% for Class A shares. The returns shown for periods prior to the inception of the Fund's Class A shares append the returns of the Fund's Class Z shares, the Fund's oldest share class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit columbiamanagement.com/mutual-funds/
appended-performance for more information.

Portfolio Diversification

as a percentage of net assets, as of 12/31/14

Top 10 Holdings

as a percentage of net assets, as of 12/31/14

1.	Ametek Aerospace/Industrial Instruments	6.2	%
2.	Donaldson Industrial Air Filtration	4.4	%
3.	Amphenol Electronic Connectors	4.3	%
4.	WNS - ADR (India) Offshore Business Process Outsourcing Services	3.9	%
5.	Mettler-Toledo International Laboratory Equipment	3.8	%
6.	SEI Investments Mutual Fund Administration & Investment Management	3.7	%
7.	F5 Network Internet Traffic Management Equipment	3.7	%
8.	LKQ Alternative Auto Parts Distribution	3.3	%
9.	CNO Financial Group Life, Long-term Care & Medical Supplement Insurance	3.3	%
10.	Nordson Dispensing Systems for Adhesives & Coatings	3.2	%

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.

Columbia Thermostat Fund^SM

In a Nutshell


Charles P. McQuaid Lead Portfolio Manager				Christopher J. Olson Co-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 Class Z shares ended the fourth quarter of 2014 up 1.78%. This compares to a 4.93% quarterly gain of the Fund's primary equity benchmark, the S&P 500 Index. The Fund's primary debt benchmark, the Barclays U.S. Aggregate Bond Index, rose 1.79% in the quarter, and the 50/50 Blended Benchmark gained 3.36% for the same period. For the annual period, the Fund gained 5.57%, while the S&P 500 rose 13.69%, the Barclays U.S. Aggregate Bond Index rose 5.97% and the 50/50 Blended Benchmark gained 9.85%.

The weighted average gain for the Fund's equity portfolio was 2.93% for the fourth quarter and 6.40% for the annual period. Columbia Large Cap Enhanced Core Fund led gains for both periods, rising 5.25% in the fourth quarter and ending the year up 15.41%.

The bond portion of the Fund had a weighted average gain of 0.78% for the fourth quarter and rose 3.64% for the annual period. Columbia U.S. Government Mortgage Fund outperformed during the fourth quarter, increasing 2.15%, and rose 3.41% from May 1, 2014, when it was added to the Fund, through the end of the year.

Fund performance fell below the benchmarks for both the fourth quarter and the year. This was disappointing as our goal for Columbia Thermostat Fund is to provide performance that falls between its bond and equity benchmarks. This lag can be attributed largely to the Fund's relatively conservative bond investments, which are intended to serve as cash substitutes. Within the equities, domestic large-cap stocks outperformed, and Columbia Thermostat's smaller cap and foreign exposure hurt performance somewhat. We believe the Fund's smaller cap and foreign exposure should serve shareholders well over the long term.

The Fund hit four reallocation triggers in the fourth quarter. The Fund's equity exposure was increased twice in October, reduced in November and increased again in December. The Fund's allocation in November fell to its minimum 10% after the S&P 500 surpassed the 2,020 level, and then increased to 15% in December as the market fell. As of the writing of this report, stock market

volatility has increased. Columbia Thermostat Fund is poised to buy equities should the stock market decline.

Results of the Funds Owned in Columbia Thermostat Fund

as of December 31, 2014

Stock Funds

Fund	Weightings in category			4th quarter			1 year
Columbia Acorn International, Class I		20	%		-2.59	%		-4.20	%
Columbia Dividend Income Fund, Class I		20	%		4.66	%		12.94	%
Columbia Acorn Fund, Class I		15	%		3.91	%		0.91	%
Columbia Contrarian Core Fund, Class I		15	%		4.73	%		13.12	%
Columbia Acorn Select, Class I		10	%		2.88	%		2.49	%
Columbia Large Cap Enhanced Core Fund, Class I		10	%		5.25	%		15.41	%
Columbia Select Large Cap Growth Fund, Class I		10	%		4.26	%		8.68	%
Weighted Average Equity Gain/Loss		100	%		2.93	%		6.40	%

Bond Funds

Fund	Weightings in category			4th quarter			1 year
Columbia Short Term Bond Fund, Class I		40	%		0.13	%		0.97	%
Columbia Intermediate Bond Fund, Class I		25	%		0.95	%		5.57	%
Columbia Income Opportunities Fund, Class I		20	%		0.85	%		4.15	%
Columbia U.S. Government Mortgage Fund, Class I		15	%		2.15	%		5.92	%
Weighted Average Income Gain/Loss		100	%		0.78	%		3.64	%

Columbia Thermostat Fund Rebalancing in the Fourth Quarter

October 3, 2014				20% stocks, 80% bonds
October 14, 2014				25% stocks, 75% bonds
November 14, 2014				10% stocks, 90% bonds
December 15, 2014				15% stocks, 85% bonds

The value of an investment in the Fund is based primarily on the performance of the underlying funds in which it invests. The Fund is subject to the risk that the investment manager's decisions regarding asset classes and underlying funds will not anticipate market trends successfully, resulting in a failure to preserve capital or lower total return.

The Fund's investments in the underlying funds may also present certain risks, including the following. Investments made by underlying funds in foreign securities, particularly those in emerging markets countries, are subject to special risks, including but not limited to a greater degree of social, political and economic volatility than is associated with domestic investments, as well as the risks associated with any differences in financial standards, including foreign taxation. Investments by the underlying funds in small- and mid-cap companies, as well as in restricted securities, pose special risks, including potential illiquidity and price volatility. Underlying funds that concentrate their investments in a single industry sector, such as technology or healthcare, are subject to the risk that companies in the same sector may be similarly affected by economic or market downturns. Risks associated with investments in bond funds include credit risk, interest rate risk, and prepayment and extension risk. Debt securities with the lowest investment grade ratings and unrated securities of comparable quality are more speculative than securities with higher ratings and may experience greater price fluctuations. These securities also tend to be more sensitive to credit risk than higher-rated securities. This is not an offer of the shares of any other mutual fund mentioned herein.

Columbia Thermostat Fund^SM

At a Glance

Total Net Assets of the Fund:
$1.2 billion

The Growth of a $10,000 Investment in Columbia Thermostat Fund^SM Class Z Shares

September 25, 2002 (Fund inception) through December 31, 2014

This chart shows the change in value of a hypothetical $10,000 investment in Class Z shares of the Fund during the stated time period.

Average Annual Total Returns for period ended December 31, 2014

	4th quarter			1 year			5 years			10 years			Life of Fund
Class Z (9/25/02 inception)		1.78	%		5.57	%		10.09	%		6.55	%		7.99	%
Class A (3/3/03 inception)
without sales charge		1.77			5.30			9.82			6.29			7.72
with sales charge		-4.11			-0.75			8.54			5.66			7.20
S&P 500® Index*		4.93			13.69			15.45			7.67			10.02
Barclays U.S. Aggregate Bond Index*		1.79			5.97			4.45			4.71			4.67

Results for other share classes can be found on Page 2.

*The Fund's primary benchmarks. Please see Page 1 for index descriptions.

Returns for Class A shown with and without the maximum initial sales charge of 5.75%. As stated in the May 1, 2014, prospectus, the Fund's annual operating expense ratio is 0.80% for Class Z shares and 1.05% for Class A shares. The returns shown for periods prior to the inception of the Fund's Class A shares append the returns of the Fund's Class Z shares, the Fund's oldest share class. These returns are adjusted to reflect any higher class-related operating expenses of the newer share classes, as applicable. Please visit columbiamanagement.com/mutual-funds/
appended-performance for more information.

Asset Allocation

as a percentage of net assets, as of 12/31/14

Portfolio Weightings

as a percentage of assets in each investment category, as of 12/31/14

Stock Mutual Funds

Columbia Acorn International, Class I	20	%
Columbia Dividend Income Fund, Class I	20	%
Columbia Acorn Fund, Class I	15	%
Columbia Contrarian Core Fund, Class I	15	%
Columbia Acorn Select, Class I	10	%
Columbia Large Cap Enhanced Core Fund, Class I	10	%
Columbia Select Large Cap Growth Fund, Class I	10	%

Bond Mutual Funds

Columbia Short Term Bond Fund, Class I	40	%
Columbia Intermediate Bond Fund, Class I	25	%
Columbia Income Opportunities Fund, Class I	20	%
Columbia U.S. Government Fund, Class I	15	%

Columbia Acorn Emerging Markets Fund^SM

In a Nutshell


Fritz Kaegi Lead Portfolio Manager				Stephen Kusmierczak Lead Portfolio Manager

P. Zachary Egan Co-Portfolio Manager				Louis J. Mendes III Co-Portfolio Manager

Columbia Acorn Emerging Markets Fund Class Z shares declined 2.36% in the final quarter of 2014, somewhat less than the Fund's primary benchmark, the S&P Emerging Markets Between $500M and $5B Index®, which fell 3.32%. For the full year, the Fund lost 4.12% compared to the benchmark gain of 1.90%. This underperformance was very disappointing, and represents the Fund's first year of underperformance versus the benchmark since inception. Losses in Fund health care and consumer discretionary stocks caused the most harm. Both of these sectors were outperformers last year and, since inception, our consumer discretionary stocks have been the single largest contributor to Fund outperformance. The Fund's annualized gain of 8.29% since its inception is well ahead of the benchmark's 3.31% return for the same period.

The biggest detractor in U.S. dollar terms for the fourth quarter was Kazakhstan retail bank and insurer Halyk Savings Bank of Kazakhstan, which dropped 26% in sympathy with lower oil prices and the potential devaluation of the Kazakh tenge following the Russian ruble's 30% devaluation. We believe that Halyk will emerge comfortably from this volatility, given its cheap valuation multiple, its dividend yield of over 5%, its robust capitalization and the perception within Kazakhstan of Halyk being the safest destination for deposits. Down 24% for the quarter, St. Shine Optical, a disposable contact lens manufacturer in Taiwan with most of its sales to Japan, faced increasing competition, causing its growth to flatten. Several Korean consumer discretionary holdings were also significant performance detractors in the quarter. Korean and Chinese fashion retailer The Basic House fell 39% in the fourth quarter as Korean sales remained slack after the Sewol ferry tragedy earlier in the year. Two gaming companies, Grand Korea Leisure and Paradise, fell 27% and 35%, respectively, following a corruption clampdown by Chinese authorities. Both casinos mainly serve Chinese gamers.

For the year, the biggest performance detractor was also a gaming company. Macau casino operator Melco International dropped 40%. Prior to this year, Melco International and Fund investments in gaming were consistent outperformers. We continue to hold these positions because we believe these highly cash generative businesses will eventually improve as mid-market growth offsets the decline in less-profitable VIP and junket businesses.

The two top performance contributors for the quarter also provided the biggest gains for the full year. Korean company Koh Young Technology provides inspection systems for printed circuit boards and was up 44% in the quarter and 126% for the year. The company is experiencing accelerating growth in its new 3D product and is growing penetration in China and in the automotive

industry. South African investment manager Coronation Fund Managers gained 18% for the quarter and 36% for the year, despite a 10% currency depreciation. The company continues to take savings product market share from banks and insurance companies, and is also growing its international business. Companies based in India were the best performing stocks in the emerging markets for the quarter and the year, gaining 16% and 51%, respectively. This rally was driven by expectations that the new Prime Minister Narendra Modi will be able to implement fundamental economic reforms. This improving country sentiment helped lift two of our best-performing holdings. Zee Entertainment is the leading programmer of pay television content in India, and gained 18% in the quarter and 28% for the year. Auto parts supplier Bosch is a subsidiary of its eponymous German parent, and returned 28% in the quarter and 92% for the year.

Following this year of underperformance, shareholders should rightfully question what we missed and whether we've changed how we invest your capital. First, we were slow in responding to the new anti-corruption policies in China. Similar efforts have been launched before, but not as effectively. Second, when we introduced the Fund, we expected that rising incomes and wealth, increasing labor participation and better education would drive strong spending growth by emerging market consumers, and that there would be companies that would capitalize on this development. While some markets are facing headwinds that are impacting growth, we believe the positive trends will return and be durable. Finally, while we are displeased by this year's underperformance, repeating prior years' outsized gains was unlikely. We are long-term investors and strive to invest in companies whose business models will enable outperformance over many years, not just a quarter or two. We believe this strategy should benefit patient investors and expect that you will watch our performance closely in 2015.

Please note that effective July 11, 2014, Columbia Acorn Emerging Markets Fund is closed to new investors and new accounts with certain exceptions. Refer to the Fund's prospectus dated May 1, 2014, as supplemented June 12, 2014, for details.

Fund's Positions in Mentioned Holdings

As a percentage of net assets, as of 12/31/14

Coronation Fund Managers	4.1	%
Zee Entertainment	3.0
Koh Young Technology	2.4
Melco International	2.4
Halyk Savings Bank of Kazakhstan	2.2
St. Shine Optical	1.4
Bosch	1.1
The Basic House	1.0
Grand Korea Leisure	0.8
Paradise	0.5

Fund holdings are as of the date given, are subject to change at any time, and are not recommendations to buy or sell any security. Top holdings exclude short-term holdings and cash, if applicable.

Columbia Acorn Emerging Markets Fund^SM

At a Glance

Total Net Assets of the Fund:
$482.3 million

The Growth of a $10,000 Investment in Columbia Acorn Emerging Markets Fund^SM Class Z Shares

August 19, 2011 (Fund inception) through December 31, 2014

This chart shows the change in value of a hypothetical $10,000 investment in Class Z shares of the Fund during the stated time period.

Average Annual Total Returns for period ended December 31, 2014

	4th quarter			1 year			Life of Fund
Class Z (8/19/11 inception)		-2.36	%		-4.12	%		8.29	%
Class A (8/19/11 inception)
without sales charge		-2.37			-4.28			8.00
with sales charge		-7.98			-9.81			6.12
S&P Emerging Markets Between $500M and $5B® Index*		-3.32			1.90			3.31

Results for other share classes can be found on Page 2.

*The Fund's primary benchmark. Please see Page 1 for index descriptions.

Returns for Class A shown with and without the maximum initial sales charge of 5.75%. As stated in the May 1, 2014, prospectus, the Fund's annual operating expense ratio is 1.59% for Class Z shares and 1.81% for Class A shares.

Portfolio Diversification

as a percentage of net assets, as of 12/31/14

Top 10 Holdings

as a percentage of net assets, as of 12/31/14

1.	Coronation Fund Managers (South Africa) South African Fund Manager	4.1	%
2.	Zee Entertainment Enterprises (India) Programmer of Pay Television Content	3.0	%
3.	AMVIG Holdings (China) Chinese Tobacco Packaging Material Supplier	2.8	%
4.	Melco Crown Resorts (Philippines) Integrated Resort Operator in Manila	2.5	%
5.	Koh Young Technology (Korea) Inspection Systems for Printed Circuit Boards	2.4	%
6.	Melco International (Hong Kong) Macau Casino Operator	2.4	%
7.	Halyk Savings Bank of Kazakhstan - GDR (Kazakhstan) Retail Bank & Insurer in Kazakhstan	2.2	%
8.	WuXi PharmaTech - ADR (China) Contract Research Organization Business in China	2.1	%
9.	Rand Merchant Insurance (South Africa) Directly Sold Property & Casualty Insurance; Holdings in other Insurers	2.1	%
10.	Nagacorp (Cambodia) Casino & Entertainment Complex in Cambodia	2.0	%

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.

Columbia Acorn European Fund^SM

In a Nutshell


Andreas Waldburg-Wolfegg Lead Portfolio Manager				Stephen Kusmierczak Co-Portfolio Manager

For the year ended December 31, 2014, Columbia Acorn European Fund Class Z shares fell 7.52%. This compares to a 5.35% decline in the Fund's primary benchmark, the S&P Europe Between $500M and $5B® Index. For the fourth quarter, the Fund outperformed the benchmark with a 0.71% decline versus the benchmark's 1.47% drop.

To provide a more meaningful analysis in this report of the Fund, we divided Europe into what we consider to be homogenous sub-regions, as follows:

Mediterranean: France, Greece, Italy, Portugal and Spain

Nordic: Denmark, Finland, Norway and Sweden

Northern and Central Europe: Austria, Belgium, Germany, Luxembourg, the Netherlands and Switzerland

United Kingdom and Ireland

Other: All other countries, including Central Eastern and Southeastern Europe

The largest average geographical region weight within the Fund over 2014 was the United Kingdom and Ireland at 34%, followed by Northern and Central Europe (24%), the Mediterranean (20%), and the Nordic countries (19%). "Other" represented 1.7% of the Fund.

The largest contributor to annual performance relative to the benchmark was the Mediterranean region (up 130 basis points*), followed by the Nordic region (up 84 basis points). Chief detractors to the Fund's annual performance were Russian stocks, which were off benchmark and caused significant damage in the first quarter, though they were strong contributors in 2013. Performance was further impacted by stock picks in the Netherlands and Belgium. In the Netherlands, the Fund was hurt by its exposure to oil sector stock Core Labs at a time when oil prices dropped dramatically. In Belgium, digital live mobile production software and systems developer EVS Broadcast Equipment suffered declining revenues as a result of reduced spending by U.S. broadcasters. The Netherlands and Belgium are part of the Northern and Central Europe region, which was up 3.5% in local currency in the Fund relative to the benchmark's 8.1% local currency gain for the year.

Looking at the fourth quarter, the Fund lost only a little of its third quarter outperformance. Several of the individual contributors and detractors from last quarter remained the same but three holdings went from being top contributors to Fund performance to being detractors from it. Among them, French postage meter machines supplier

Neopost dropped at the beginning of November when the company announced that the French government had reduced the scope of its contract renewal, thereby impacting revenues for the current and next year. The shares fell back to the mid-$50 range, below levels we experienced in January 2014 when we first increased the position size. We've opted to hold the stock based on our confidence that the high yield compensates the Fund while the company diversifies into postal lockers and shipping solutions.

Many factors are currently impacting the performance of the European economies. We believe that an acceleration of reforms in France and in Italy may help performance, and the final introduction of quantitative easing sometime in the first half of this current year may also benefit the European economies. While we believe the euro's weakness against the U.S. dollar foreshadowed this widely anticipated event, we also believe that quantitative easing by the European Central Bank should allow exporters in the region to position themselves more aggressively in the global marketplace. It is also uncertain how recent events in France and the increasing reality of terrorist threats will impact European economies. In the meantime, there's much to do for the stock picker in a region that is among the most attractively valued worldwide.

Fund's Positions in Mentioned Holdings

As a percentage of net assets, as of 12/31/14

Neopost	2.6	%
EVS Broadcast Equipment	1.1
Core Labs	0.6

Fund holdings are as of the date given, are subject to change at any time, and are not recommendations to buy or sell any security. Top holdings exclude short-term holdings and cash, if applicable.

* A basis point is 1/100^th of a percent.

Columbia Acorn
European Fund^SM

At a Glance

Total Net Assets of the Fund:
$36.6 million

The Growth of a $10,000 Investment in Columbia Acorn European Fund^SM Class Z Shares

August 19, 2011 (Fund inception) through December 31, 2014

This chart shows the change in value of a hypothetical $10,000 investment in Class Z shares of the Fund during the stated time period.

Average Annual Total Returns for period ended December 31, 2014

	4th quarter			1 year			Life of Fund
Class Z (8/19/11 inception)		-0.71	%		-7.52	%		12.40	%
Class A (8/19/11 inception)
without sales charge		-0.77			-7.77			12.10
with sales charge		-6.45			-13.09			10.15
S&P Europe Between $500M and $5B® Index*		-1.47			-5.35			13.80

Results for other share classes can be found on Page 2.

*The Fund's primary benchmark. Please see Page 1 for index descriptions.

Returns for Class A shown with and without the maximum initial sales charge of 5.75%. As stated in the May 1, 2014, prospectus, the Fund's annual operating expense ratio is 1.51% for Class Z shares and 1.76% for Class A shares.

Portfolio Diversification

as a percentage of net assets, as of 12/31/14

Top 10 Holdings

as a percentage of net assets, as of 12/31/14

1.	Assura (United Kingdom) Primary Health Care Property Developer	3.2	%
2.	Partners Group (Switzerland) Private Markets Asset Management	2.8	%
3.	Neopost (France) Postage Meter Machines	2.6	%
4.	Spirax Sarco (United Kingdom) Steam Systems for Manufacturing & Processing Industries	2.6	%
5.	Aurelius (Germany) European Turnaround Investor	2.3	%
6.	DIA (Spain) Discount Retailer in Spain & Latin America	2.3	%
7.	NORMA Group (Germany) Clamps for Automotive & Industrial Applications	2.2	%
8.	Aalberts Industries (Netherlands) Flow Control & Heat Treatment	2.2	%
9.	Geberit (Switzerland) Plumbing Supplies	2.1	%
10.	Babcock International (United Kingdom) Public Sector Outsourcer	2.0	%

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.

Columbia Acorn® Fund

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	9/30/14		12/31/14
Purchases
Information
Amber Road		1,046,288		2,000,000
Audience		1,753,625		2,150,000
Bankrate		4,800,000		6,300,300
Cadence Design Systems		0		2,000,000
DemandWare		1,000,000		1,152,000
E2Open		2,225,000		2,575,000
Fleetmatics		0		698,269
FLIR Systems		876,000		1,383,000
Global Eagle Entertainment		0		1,000,000
Globalstar		26,000,000		31,000,000
GTT Communications		1,430,000		1,950,000
Liquidity Services		1,300,000		1,600,000
Navigant Consulting		4,075,000		4,128,523
NetSuite		550,000		640,000
SPS Commerce		1,035,000		1,330,000
Textura		589,372		800,283
VeriFone Holdings		539,000		849,000
Verint Systems		0		365,000
Verisign		0		350,000
Vonage		12,165,736		14,044,775
Workiva		0		826,390
Zayo Group Holdings		0		925,000
Industrial Goods & Services
Allegion		0		188,400
Fortune Brands Home & Security		930,000		1,050,000
Lindsay		0		93,147
LKQ		5,148,000		5,423,000
Lumber Liquidators		400,000		500,000
Oshkosh Corporation		1,724,000		2,100,000
Quanta Services		3,000,000		3,309,894
Thermon		1,827,007		1,940,094
Consumer Goods & Services
Buffalo Wild Wings		0		157,000
Fox Factory Holding		52,654		537,804
Freshpet		0		243,000
Gentex		653,000		913,000
Hertz		3,000,000		3,300,000
Wayfair		0		433,000
Zulily		1,170,000		1,350,000
Finance
Eaton Vance		3,052,000		3,283,508
Leucadia National		2,820,000		3,552,000
Liberty Tax		400,000		472,000
WEX		670,000		720,000

	Number of Shares
	9/30/14		12/31/14
Health Care
Abaxis		506,020		752,000
Align Technology		0		448,000
Bio-Techne		1,040,000		1,169,200
Intercept Pharmaceuticals		153,000		319,200
Medidata Solutions		1,384,000		1,549,500
VWR		0		1,375,400
Wright Medical Group		647,000		1,255,500
Other Industries
Amerco		150,000		170,000
Genesee & Wyoming		300,000		380,000
Heartland Express		400,000		496,024
Kirby		530,000		730,000
Energy & Minerals
Allied Nevada Gold		3,650,000		7,103,513
Bonanza Creek Energy		0		203,000
Core Labs (Netherlands)		492,000		505,000
Kirkland Lake Gold (Canada)		5,500,000		6,347,100
PDC Energy		262,000		501,000
Petromanas (Canada)		64,685,000		67,500,000
RGS Energy		4,699,210		5,000,000
ShaMaran Petroleum (Iraq)		28,700,000		28,962,000
Silvercrest Mines		0		3,412,300
US Silica		503,000		599,000

See accompanying notes to financial statements.

	Number of Shares
	9/30/14		12/31/14
Sales
Information
Atmel		5,390,000		4,717,000
Amphenol		6,312,000		5,416,000
Avnet		2,738,000		1,887,000
Belden		507,000		475,000
Commvault Systems		550,000		0
Concur Technologies		260,000		0
Crown Castle International		940,000		800,000
Exa		699,967		554,391
Genpact		1,983,000		1,405,000
Hackett Group		3,274,000		2,903,719
Hexagon (Sweden)		2,693,000		1,622,000
iGATE		3,775,000		3,600,000
II-VI		1,604,000		0
Infinera		2,983,000		2,711,000
IPG Photonics		1,620,000		1,504,000
Ixia		1,040,000		1,006,000
Mettler-Toledo International		1,351,638		1,162,000
Monolithic Power Systems		699,000		427,000
Pandora Media		3,456,000		2,843,000
Plexus		684,918		451,458
RealPage		1,050,000		0
RetailMeNot		2,199,707		1,112,930
Rightmove (United Kingdom)		257,000		155,205
Rogers		624,000		569,000
Sanmina		3,800,000		3,200,000
SBA Communications		2,360,000		1,600,000
Semtech		560,000		0
Solera Holdings		1,176,000		989,000
Stratasys		395,000		371,000
Syntel		746,000		497,000
Tangoe		1,750,000		641,952
Trimble Navigation		4,362,000		3,651,000
TripAdvisor		625,000		0
Tyler Technologies		500,000		470,000
Ultratech		615,000		0
Virtusa		1,835,000		1,658,000
WNS - ADR (India)		2,112,805		2,025,000
Zebra Technologies		803,000		501,000
Industrial Goods & Services
Aalberts Industries (Netherlands)		2,321,000		2,189,385
Acuity Brands		1,209,000		960,000
Airgas		930,000		880,000
Ametek		7,996,000		7,130,000
Boise Cascade		883,000		600,000
CAE (Canada)		1,894,000		0
Chicago Bridge & Iron		1,631,000		1,299,000
Donaldson		8,400,000		7,952,000
Dorman Products		881,086		867,721
Drew Industries		1,680,000		1,610,000

	Number of Shares
	9/30/14		12/31/14
ESCO Technologies		2,185,000		1,948,000
FMC Corporation		350,000		0
Generac		4,000,000		3,632,000
HEICO		3,828,750		3,626,750
Insperity		822,000		715,000
KAR Auction Services		1,375,000		1,316,000
Kennametal		3,182,000		2,674,000
Marel (Iceland)		10,000,000		0
Middleby		1,081,200		1,050,200
Mobile Mini		1,250,000		900,000
Moog		2,974,827		2,456,000
Nordson		3,400,000		3,130,000
Novozymes (Denmark)		1,090,000		907,458
PolyOne		700,000		0
Sociedad Quimica y Minera de Chile - ADR (Chile)		917,486		0
Toro		1,529,000		1,486,000
Ushio (Japan)		1,500,000		0
Valmont Industries		225,000		0
WABCO Holdings		1,210,000		1,176,000
Wabtec		1,083,000		1,053,000
Waste Connections		1,500,000		1,100,000
WESCO International		1,687,000		1,553,000
Consumer Goods & Services
Avis Budget Group		3,950,000		3,700,000
B&G Foods		1,029,000		591,000
Blackhawk Network		900,000		700,000
Boulder Brands		3,947,000		3,484,000
Burlington Stores		1,381,000		786,900
Caesarstone (Israel)		812,360		630,000
Casey's General Stores		1,475,839		1,027,709
Choice Hotels		849,483		754,483
DeVry		1,075,000		800,000
DIA (Spain)		2,557,000		837,052
Domino's Pizza		719,000		489,000
DSW		945,000		533,500
Expedia		1,050,000		0
Fiesta Restaurant Group		1,001,000		878,000
Fossil		646,845		362,145
GNC Holdings		819,000		478,000
Groupon		4,972,000		2,010,000
Herman Miller		916,000		0
Interface		2,920,000		2,758,000
Kate Spade & Company		2,366,000		1,796,000
Knoll		3,669,000		3,366,000
KT&G (Korea)		229,000		0
Massmart Holdings (South Africa)		852,000		0
Melco Crown Entertainment - ADR (Hong Kong)		900,000		0
Michaels Stores		1,238,262		1,162,000

See accompanying notes to financial statements.

Columbia Acorn® Fund

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

	Number of Shares
	9/30/14		12/31/14
Sales (continued)
Consumer Goods & Services—continued
Papa John's International		492,000		478,000
Pier 1 Imports		1,762,555		0
Pool		1,818,000		1,565,000
Popeyes Louisiana Kitchen		1,350,000		700,000
PVH		793,000		456,000
Shutterfly		1,660,000		970,000
The Chefs' Warehouse		900,000		875,000
The Fresh Market		1,535,000		1,492,000
ULTA		1,044,000		613,000
United Natural Foods		1,340,000		1,303,000
Urban Outfitters		900,000		508,000
Vail Resorts		1,430,000		1,268,600
Williams-Sonoma		1,508,000		874,200
Finance
Alliance Data Systems		490,000		360,000
Brown & Brown		1,650,000		0
CNO Financial Group		8,800,000		7,600,000
Enstar Group		250,000		185,000
First Busey		4,841,882		4,328,500
Hudson Valley		843,000		0
MB Financial		2,860,000		2,580,000
McGrath Rentcorp		2,000,000		1,580,000
Rand Merchant Insurance (South Africa)		10,837,000		8,658,000
Selective Insurance Group		2,625,000		714,574
Sprott (Canada)		11,436,300		11,000,000
TCF Financial		950,000		0
Valley National Bancorp		3,323,500		1,573,000
Wisdom Tree		1,000,000		500,000
Heath Care
Akorn		5,089,000		4,845,000
Allscripts Healthcare Solutions		6,724,600		2,746,200
Alnylam Pharmaceuticals		423,400		362,300
BioMarin Pharmaceutical		737,000		320,200
Castlight Health		890,000		863,500
Celldex Therapeutics		2,750,000		2,401,400
Cepheid		5,836,000		5,350,800
Envision Healthcare Holdings		1,277,000		1,239,000
HealthSouth		2,100,000		1,666,323
Henry Schein		687,000		291,100
NPS Pharmaceuticals		963,000		934,400
Revance Therapeutics		476,000		0
Sarepta Therapeutics		2,552,000		2,523,900
Seattle Genetics		4,001,000		3,398,400
Sirona Dental Systems		833,000		460,900
Synageva BioPharma		2,493,309		2,419,209
Ultragenyx Pharmaceutical		1,624,689		1,164,974

	Number of Shares
	9/30/14		12/31/14
Other Industries
Coresite Realty		880,000		0
Deltic Timber		90,000		39,381
Extra Space Storage		2,100,000		2,000,000
Hudson Pacific Properties		975,000		0
JB Hunt Transport Services		1,000,000		940,000
Kite Realty Group		1,172,500		0
Mapletree Commercial Trust (Singapore)		20,282,089		0
Northeast Utilities		1,900,000		1,600,000
Orix JREIT (Japan)		10,362		0
Rush Enterprises, Class A		2,704,100		2,650,000
St. Joe		1,800,000		872,926
Wisconsin Energy		650,000		500,000
Energy & Minerals
Alamos Gold (Canada)		4,000,000		3,500,000
Bill Barrett Corporation		770,000		0
Black Diamond Group (Canada)		463,863		214,100
Duluth Metals (Canada)		5,544,000		0
FMC Technologies		3,858,000		370,000
Laredo Petroleum		928,000		0
Pacific Rubiales Energy (Colombia)		2,200,000		1,800,000
Parsley Energy		891,000		0
Rice Energy		570,000		0
Rosetta Resources		2,322,600		1,849,600
WPX Energy		1,358,000		1,210,000

See accompanying notes to financial statements.

Columbia Acorn® Fund

Statement of Investments, December 31, 2014

Number of Shares			Value
			Equities: 97.7%
Information 27.2%
		> Business Software 6.9%
	2,500,000	Ansys (a)	$	205,000,000
		Simulation Software for Engineers & Designers
	5,200,000	Informatica (a)		198,302,000
		Enterprise Data Integration Software
	1,330,000	SPS Commerce (a)(b)		75,317,900
		Supply Chain Management Software Delivered via the Web
	640,000	NetSuite (a)		69,868,800
		End-to-end IT Systems Solution Delivered via the Web
	1,152,000	DemandWare (a)		66,286,080
		E-Commerce Website Platform for Retailers & Apparel Manufacturers
	450,000	Ultimate Software (a)		66,066,750
		Human Capital Management Systems
	470,000	Tyler Technologies (a)		51,436,800
		Financial, Tax, Court & Document Management Systems for Local Governments
	989,000	Solera Holdings		50,617,020
		Software for Automotive Insurance Claims Processing
	1,622,000	Hexagon (Sweden)		50,037,952
		Design, Measurement & Visualization Software & Equipment
	2,000,000	Cadence Design Systems (a)		37,940,000
		Electronic Design Automation Software
	3,741,000	InContact (a)(b)		32,883,390
		Call Center Systems Delivered via the Web & Telco Services
	610,000	Envestnet (a)		29,975,400
		Technology Platform for Investment Advisors
	698,269	Fleetmatics (a)		24,781,567
		Fleet Management Software
	2,575,000	E2Open (a)(b)(c)		24,745,750
		Supply Chain Management Software & Supplier/Partner Network
	800,283	Textura (a)(c)		22,784,057
		Construction Vendor Management Software
	365,000	Verint Systems (a)		21,272,200
		Contact Center & Security Software
	2,000,000	Amber Road (a)(b)		20,440,000
		Global Trade Management Software Delivered via the Web
	708,300	Kinaxis (Canada) (a)		11,278,662
		Supply Chain Planning & Analytics Software
	826,390	Workiva (a)		11,073,626
		Software Platform for Report Creation
	641,952	Tangoe (a)		8,364,635
		Software Solution for Managing Communication Expense & Devices

Number of Shares			Value
	1,728,000	Five9 (a)(c)	$	7,741,440
		Call Center Software
	554,391	Exa (a)		6,530,726
		Simulation Software
	540,000	Covisint (a)		1,431,000
		Collaboration Software Platform Provider
				1,094,175,755
		> Instrumentation 3.8%
	1,162,000	Mettler-Toledo International (a)		351,458,520
		Laboratory Equipment
	1,504,000	IPG Photonics (a)(c)		112,679,680
		Fiber Lasers
	3,651,000	Trimble Navigation (a)		96,897,540
		GPS-based Instruments
	1,383,000	FLIR Systems		44,684,730
		Infrared Cameras
				605,720,470
		> Computer Hardware & Related Equipment 3.0%
	5,416,000	Amphenol		291,434,960
		Electronic Connectors
	569,000	Rogers (a)		46,339,360
		Printed Circuit Materials & High-performance Foams
	501,000	Zebra Technologies (a)		38,782,410
		Bar Code Printers
	475,000	Belden		37,434,750
		Specialty Cable
	849,000	VeriFone Holdings (a)		31,582,800
		Point of Sale Systems
	371,000	Stratasys (a)(c)		30,833,810
		Rapid Prototyping & Direct Digital Manufacturing Systems
				476,408,090
		> Mobile Communications 2.4%
	1,600,000	SBA Communications (a)		177,216,000
		Communications Towers
	31,000,000	Globalstar (a)(c)		85,250,000
		Satellite Mobile Voice & Data Carrier
	800,000	Crown Castle International		62,960,000
		Communications Towers
	2,000,000	Gogo (a)(c)		33,060,000
		Provider of Wi-Fi on Airplanes
	1,000,000	Global Eagle Entertainment (a)		13,610,000
		Provider of Entertainment & Wi-Fi on Airplanes
	2,150,000	Audience (a)(b)(c)		9,460,000
		Improving Voice Quality for Mobile Devices
				381,556,000
		> Computer Services 2.3%
	3,600,000	iGATE (a)		142,128,000
		IT & Business Process Outsourcing Services

See accompanying notes to financial statements.

Columbia Acorn® Fund

Statement of Investments, continued

Number of Shares			Value
		> Computer Services—continued
	1,658,000	Virtusa (a)(b)	$	69,088,860
		Offshore IT Outsourcing
	2,025,000	WNS - ADR (India) (a)		41,836,500
		Offshore Business Process Outsourcing Services
	1,407,000	ExlService Holdings (a)		40,394,970
		Business Process Outsourcing
	1,405,000	Genpact (a)		26,596,650
		Business Process Outsourcing
	2,903,719	Hackett Group (b)		25,523,690
		IT Integration & Best Practice Research
	497,000	Syntel (a)		22,355,060
		Offshore IT Services
				367,923,730
		> Business Information & Marketing Services 1.9%
	1,900,000	Verisk Analytics (a)		121,695,000
		Risk & Decision Analytics
	6,300,300	Bankrate (a)(b)		78,312,729
		Internet Advertising for the Insurance, Credit Card & Banking Markets
	4,128,523	Navigant Consulting (a)(b)		63,455,399
		Financial Consulting Firm
	2,570,000	RPX (a)		35,414,600
		Patent Aggregation & Defensive Patent Consulting
				298,877,728
		> Telephone & Data Services 1.0%
	2,200,000	Cogent Communications		77,858,000
		Internet Data Pipelines
	925,000	Zayo Group Holdings (a)(c)		28,277,250
		Fiber Optic Data Communications
	1,950,000	GTT Communications (a)(b)		25,798,500
		Provider of High Capacity Data Transit
	2,800,000	Boingo Wireless (a)(b)		21,476,000
		Wholesale & Retail Wi-Fi Networks
	4,000,000	Towerstream (a)(b)(c)		7,400,000
		High Speed Wireless, Rooftop Antenna Space & Wi-Fi Offload
				160,809,750
		> Financial Processors 0.9%
	1,700,000	Global Payments		137,241,000
		Credit Card Processor
	1,600,000	Liquidity Services (a)(b)		13,072,000
		E-Auctions for Surplus & Salvage Goods
				150,313,000
		> Telecommunications Equipment 0.9%
	582,000	F5 Networks (a)		75,930,630
		Internet Traffic Management Equipment
	2,711,000	Infinera (a)		39,905,920
		Optical Networking Equipment

Number of Shares			Value
	1,118,000	CalAmp (a)	$	20,459,400
		Machine-to-machine Communications
	1,006,000	Ixia (a)		11,317,500
		Telecom Network Test Equipment
				147,613,450
		> Internet Related 0.9%
	14,044,775	Vonage (a)(b)		53,510,593
		Business & Consumer Internet Telephony
	2,843,000	Pandora Media (a)		50,690,690
		Streaming Music
	350,000	Verisign (a)		19,950,000
		Internet Domain Registry for .com/.net
	1,112,930	RetailMeNot (a)(c)		16,271,036
		Digital Coupon Marketplace
	155,205	Rightmove (United Kingdom)		5,412,491
		Internet Real Estate Listings
				145,834,810
		> Semiconductors & Related Equipment 0.7%
	4,717,000	Atmel (a)		39,599,215
		Microcontrollers, Radio Frequency & Memory Semiconductors
	367,000	Littelfuse		35,477,890
		Little Fuses
	427,000	Monolithic Power Systems		21,238,980
		High Performance Analog & Mixed Signal Integrated Circuits
	2,500,000	Rubicon Technology (a)(b)(c)		11,425,000
		Producer of Sapphire for the Lighting, Electronics & Automotive Industries
				107,741,085
		> Cable TV 0.6%
	800,000	Liberty Global Series A (a)		40,164,000
	800,000	Liberty Global Series C (a)		38,648,000
		Cable TV Franchises Outside the U.S.
	670,000	Discovery Series C (a)		22,592,400
		Cable TV Programming
				101,404,400
		> Contract Manufacturing 0.6%
	3,200,000	Sanmina (a)		75,296,000
		Electronic Manufacturing Services
	451,458	Plexus (a)		18,604,584
		Electronic Manufacturing Services
				93,900,584
		> Electronics Distribution 0.5%
	1,887,000	Avnet		81,178,740
		Electronic Components Distribution
		> Entertainment Programming 0.5%
	1,250,000	IMAX (Canada) (a)(c)		38,625,000
		IMAX Movies, Theatre Equipment & Theatre Joint Ventures

See accompanying notes to financial statements.

Number of Shares			Value
		> Entertainment Programming—continued
	5,500,000	Zee Entertainment Enterprises (India)	$	33,037,929
		Programmer of Pay Television Content
				71,662,929
		> Advertising 0.3%
	1,000,000	Lamar Advertising		53,640,000
		Outdoor Advertising
Information: Total				4,338,760,521
Industrial Goods & Services 24.1%
		> Machinery 14.7%
	7,130,000	Ametek		375,251,900
		Aerospace/Industrial Instruments
	7,952,000	Donaldson (b)		307,185,760
		Industrial Air Filtration
	3,130,000	Nordson (b)		244,014,800
		Dispensing Systems for Adhesives & Coatings
	2,456,000	Moog (a)(b)		181,817,680
		Motion Control Products for Aerospace, Defense & Industrial Markets
	3,626,750	HEICO (b)		171,762,880
		FAA-approved Aircraft Replacement Parts
	3,632,000	Generac (a)(b)(c)		169,832,320
		Standby Power Generators
	1,176,000	WABCO Holdings (a)		123,221,280
		Truck & Bus Component Supplier
	1,100,000	Pall		111,331,000
		Life Science, Water & Industrial Filtration
	1,050,200	Middleby (a)		104,074,820
		Manufacturer of Cooking Equipment
	2,100,000	Oshkosh Corporation		102,165,000
		Specialty Truck Manufacturer
	2,674,000	Kennametal		95,702,460
		Consumable Cutting Tools
	1,486,000	Toro		94,821,660
		Turf Maintenance Equipment
	1,053,000	Wabtec		91,495,170
		Freight & Transit Component Supplier
	1,948,000	ESCO Technologies (b)		71,881,200
		Industrial Filtration & Advanced Measurement Equipment
	867,721	Dorman Products (a)(c)		41,884,893
		Aftermarket Auto Parts Distributor
	664,400	Neopost (France)		37,902,569
		Postage Meter Machines
	705,000	Rexnord (a)		19,888,050
		Manufacturer of Mechanical Power Transmission Parts & Water Mgmt. Equipment
				2,344,233,442

Number of Shares			Value
		> Other Industrial Services 2.4%
	5,423,000	LKQ (a)	$	152,494,760
		Alternative Auto Parts Distribution
	1,800,000	Expeditors International of Washington		80,298,000
		International Freight Forwarder
	1,500,000	Forward Air		75,555,000
		Freight Transportation between Airports
	1,316,000	KAR Auction Services		45,599,400
		Auto Auctions
	900,000	Mobile Mini		36,459,000
		Portable Storage Units Leasing
				390,406,160
		> Construction 1.9%
	90,000	NVR (a)		114,779,700
		Homebuilder
	1,299,000	Chicago Bridge & Iron		54,532,020
		Engineering & Construction for Liquefied Natural Gas & Petrochemicals
	1,050,000	Fortune Brands Home & Security		47,533,500
		Home Building Supplies & Small Locks
	3,592,200	PGT (a)(b)		34,592,886
		Wind Resistant Windows & Doors
	500,000	Lumber Liquidators (a)(c)		33,155,000
		Hardwood Flooring Retailer
	188,400	Allegion		10,448,664
		Mechanical & Electronic Security Systems
				295,041,770
		> Industrial Distribution 1.7%
	1,553,000	WESCO International (a)		118,354,130
		Industrial Distributor
	880,000	Airgas		101,358,400
		Industrial Gas Distributor
	1,545,000	MRC Global (a)		23,406,750
		Industrial Distributor
	600,000	Boise Cascade (a)		22,290,000
		Wood Products Manufacturer & Distributor
				265,409,280
		> Electrical Components 1.1%
	960,000	Acuity Brands		134,467,200
		Commercial Lighting Fixtures
	1,940,094	Thermon (a)(b)		46,930,874
		Global Engineered Thermal Solutions
				181,398,074
		> Industrial Materials & Specialty Chemicals 0.8%
	1,610,000	Drew Industries (a)(b)		82,222,700
		RV & Manufactured Home Components
	907,458	Novozymes (Denmark)		38,198,138
		Industrial Enzymes
				120,420,838

See accompanying notes to financial statements.

Columbia Acorn® Fund

Statement of Investments, continued

Number of Shares			Value
		> Outsourcing Services 0.7%
	3,309,894	Quanta Services (a)	$	93,967,890
		Electrical Transmission & Pipeline Contracting Services
	715,000	Insperity		24,231,350
		Professional Employer Organization
				118,199,240
		> Conglomerates 0.4%
	2,189,385	Aalberts Industries (Netherlands)		64,567,253
		Flow Control & Heat Treatment
		> Waste Management 0.3%
	1,100,000	Waste Connections		48,389,000
		Solid Waste Management
		> Water 0.1%
	93,147	Lindsay (c)		7,986,424
		Center Pivot Irrigation Systems for Farmland & Highway Infrastructure
Industrial Goods & Services: Total				3,836,051,481
Consumer Goods & Services 13.3%
		> Retail 3.7%
	1,027,709	Casey's General Stores		92,822,677
		Owner/Operator of Convenience Stores
	613,000	ULTA (a)		78,365,920
		Specialty Beauty Product Retailer
	874,200	Williams-Sonoma		66,159,456
		Home Goods & Furnishing Retailer
	1,492,000	The Fresh Market (a)(c)		61,470,400
		Specialty Food Retailer
	1,796,000	Kate Spade & Company (a)		57,489,960
		Global Lifestyle Brand
	970,000	Shutterfly (a)		40,444,150
		Internet Photo-centric Retailer
	362,145	Fossil (a)		40,103,937
		Watch Designer & Retailer
	786,900	Burlington Stores (a)		37,188,894
		Off-price Apparel Retailer
	1,350,000	Zulily (a)(c)		31,590,000
		E-Commerce Retailer Offering Flash Sale Events
	1,162,000	Michaels Stores (a)		28,736,260
		Craft & Hobby Specialty Retailer
	533,500	DSW		19,899,550
		Branded Footwear Retailer
	508,000	Urban Outfitters (a)		17,846,040
		Multi-channel Apparel & Accessory Retailer
	2,100,000	Gaiam (a)(b)		14,973,000
		Promoter of Healthy Living through Catalogs, E-Commerce & Gaiam TV
	837,052	DIA (Spain)		5,671,933
		Discount Retailer in Spain & Latin America
				592,762,177

Number of Shares			Value
		> Travel 3.5%
	3,700,000	Avis Budget Group (a)	$	245,421,000
		Car Rental Company
	1,268,600	Vail Resorts		115,607,518
		Ski Resort Operator & Developer
	3,300,000	Hertz (a)		82,302,000
		U.S. Rental Car Operator
	2,142,000	HomeAway (a)		63,788,760
		Vacation Rental Online Marketplace
	754,483	Choice Hotels		42,266,137
		Franchisor of Budget Hotel Brands
				549,385,415
		> Consumer Goods Distribution 1.6%
	1,303,000	United Natural Foods (a)		100,754,475
		Distributor of Natural/Organic Foods to Grocery Stores
	1,565,000	Pool		99,283,600
		Swimming Pool Supplies & Equipment Distributor
	478,000	GNC Holdings		22,446,880
		Specialty Retailer of Health & Wellness Products
	875,000	The Chefs' Warehouse (a)		20,160,000
		Distributor of Specialty Foods to Fine Dining Restaurants
	2,010,000	Groupon (a)		16,602,600
		Global Marketplace for Deals
				259,247,555
		> Restaurants 1.2%
	878,000	Fiesta Restaurant Group (a)		53,382,400
		Owns/Operates Two Restaurant Chains: Pollo Tropical & Taco Cabana
	489,000	Domino's Pizza		46,049,130
		Franchisor of Pizza Restaurants
	700,000	Popeyes Louisiana Kitchen (a)		39,389,000
		Popeyes Restaurants
	157,000	Buffalo Wild Wings (a)		28,319,660
		Restaurants
	478,000	Papa John's International		26,672,400
		Franchisor of Pizza Restaurants
				193,812,590
		> Furniture & Textiles 1.1%
	3,366,000	Knoll (b)		71,258,220
		Office Furniture
	2,758,000	Interface		45,424,260
		Modular Carpet
	630,000	Caesarstone (Israel)		37,686,600
		Quartz Countertops
	700,000	La-Z-Boy		18,788,000
		Upholstery Giant
	433,000	Wayfair (a)(c)		8,595,050
		Online Retailer of Home Furnishings
				181,752,130

See accompanying notes to financial statements.

Number of Shares			Value
		> Other Durable Goods 0.8%
	1,900,000	Select Comfort (a)	$	51,357,000
		Specialty Mattresses
	500,000	Cavco Industries (a)(b)		39,635,000
		Manufactured Homes
	913,000	Gentex		32,986,690
		Manufacturer of Auto Parts
				123,978,690
		> Food & Beverage 0.4%
	3,484,000	Boulder Brands (a)(b)		38,533,040
		Healthy Food Products
	591,000	B&G Foods		17,670,900
		Acquirer of Small Food Brands
	243,000	Freshpet (a)(c)		4,145,580
		Fresh Pet Food Manufacturer & Marketer
	1,665,270	GLG Life Tech (Canada) (a)		458,673
		Producer of an All-natural Sweetener Extracted from the Stevia Plant
				60,808,193
		> Apparel 0.4%
	456,000	PVH		58,445,520
		Apparel Wholesaler & Retailer
		> Educational Services 0.2%
	800,000	DeVry		37,976,000
		Postsecondary Degree Services
		> Other Consumer Services 0.2%
	700,000	Blackhawk Network (a)		26,383,000
		Third-party Distributer of Prepaid Content, Mostly Gift Cards
		> Nondurables 0.1%
	611,000	Prestige Brands Holdings (a)		21,213,920
		Household & Personal Care Products
		> Leisure Products 0.1%
	641,000	Performance Sports Group (a)		11,531,590
		Sporting Goods Manufacturer
	537,804	Fox Factory Holding (a)		8,728,559
		High Performance Suspension Systems for Leisure Market
				20,260,149
Consumer Goods & Services: Total				2,126,025,339
Finance 12.6%
		> Banks 4.3%
	9,000,000	Associated Banc-Corp (b)		167,670,000
		Midwest Bank
	1,800,000	BOK Financial		108,072,000
		Tulsa-based Southwest Bank
	840,000	SVB Financial Group (a)		97,498,800
		Bank to Venture Capitalists
	2,580,000	MB Financial		84,778,800
		Chicago Bank
	940,000	City National		75,961,400
		Bank & Asset Manager
	1,900,000	Hancock Holding		58,330,000
		Gulf Coast Bank

Number of Shares			Value
	1,162,000	Sandy Spring Bancorp	$	30,304,960
		Baltimore & Washington, D.C. Bank
	4,328,500	First Busey		28,178,535
		Illinois Bank
	2,136,500	TrustCo Bank		15,510,990
		New York State Bank
	1,573,000	Valley National Bancorp		15,273,830
		New Jersey/New York Bank
	2,004,600	Cascade Bancorp (a)		10,403,874
		Central Oregon & Idaho Bank
				691,983,189
		> Brokerage & Money Management 3.0%
	7,368,774	SEI Investments		295,045,711
		Mutual Fund Administration & Investment Management
	3,283,508	Eaton Vance		134,393,982
		Specialty Mutual Funds
	11,000,000	Sprott (Canada) (c)		23,102,083
		Asset Manager Focused on Resources, Particularly Gold & Silver
	1,356,758	Coronation Fund Managers (South Africa)		13,426,993
		South African Fund Manager
	500,000	Wisdom Tree		7,837,500
		Fund Manager with ETF Specialty
				473,806,269
		> Insurance 2.5%
	7,600,000	CNO Financial Group		130,872,000
		Life, Long-term Care & Medical Supplement Insurance
	2,275,000	Allied World Assurance Company Holdings		86,268,000
		Commercial Lines Insurance/ Reinsurance
	1,100,000	HCC Insurance Holdings		58,872,000
		Specialty Insurance
	800,000	RLI		39,520,000
		Specialty Insurance
	8,658,000	Rand Merchant Insurance (South Africa)		30,582,082
		Directly Sold Property & Casualty Insurance; Holdings in other Insurers
	185,000	Enstar Group (a)		28,284,650
		Insurance/Reinsurance & Related Services
	714,574	Selective Insurance Group		19,414,976
		Commercial & Personal Lines Insurance
				393,813,708
		> Finance Companies 1.1%
	808,343	World Acceptance (a)(b)(c)		64,222,852
		Personal Loans
	1,580,000	McGrath Rentcorp (b)		56,658,800
		Mini Rental Conglomerate

See accompanying notes to financial statements.

Columbia Acorn® Fund

Statement of Investments, continued

Number of Shares			Value
		> Finance Companies—continued
	1,500,000	CAI International (a)(b)	$	34,800,000
		International Container Leasing
	902,210	Marlin Business Services (b)		18,522,371
		Small Equipment Leasing
				174,204,023
		> Credit Cards 1.1%
	360,000	Alliance Data Systems (a)		102,978,000
		Diversified Credit Card Provider
	720,000	WEX (a)		71,222,400
		Card Processor
				174,200,400
		> Diversified Financial Companies 0.6%
	3,552,000	Leucadia National		79,635,840
		Holding Company
	472,000	Liberty Tax (a)		16,869,280
		Tax Preparation Company
				96,505,120
Finance: Total				2,004,512,709
Health Care 10.2%
		> Biotechnology & Drug Delivery 3.8%
	2,419,209	Synageva BioPharma (a)(b)(c)		224,478,403
		Biotech Focused on Orphan Diseases
	3,398,400	Seattle Genetics (a)(c)		109,190,592
		Antibody-based Therapies for Cancer
	1,164,974	Ultragenyx Pharmaceutical (a)		51,119,059
		Biotech Focused on "Ultra-Orphan" Drugs
	319,200	Intercept Pharmaceuticals (a)(c)		49,795,200
		Biotech Developing Drugs for Several Diseases
	2,401,400	Celldex Therapeutics (a)(c)		43,825,550
		Biotech Developing Drugs for Cancer
	2,523,900	Sarepta Therapeutics (a)(b)(c)		36,520,833
		Biotech Focused on Rare Diseases
	362,300	Alnylam Pharmaceuticals (a)		35,143,100
		Biotech Developing Drugs for Rare Diseases
	934,400	NPS Pharmaceuticals (a)		33,423,488
		Orphan Drugs & Healthy Royalties
	320,200	BioMarin Pharmaceutical (a)		28,946,080
		Biotech Focused on Orphan Diseases
	359,944	MicroDose Therapeutx Contingent Value Rights (a)(d)(e)		529,118
		Drug Inhaler Development
				612,971,423
		> Medical Supplies 3.0%
	5,350,800	Cepheid (a)(b)		289,692,312
		Molecular Diagnostics
	1,169,200	Bio-Techne		108,034,080
		Cytokines, Antibodies & other Reagents for Life Science

Number of Shares			Value
	291,100	Henry Schein (a)	$	39,633,265
		Large Distributor of Dental, Vet & Medical Products
	1,375,400	VWR (a)(c)		35,581,598
		Distributor of Lab Supplies
				472,941,255
		> Health Care Services 1.4%
	1,549,500	Medidata Solutions (a)		73,988,625
		Cloud-based Software for Drug Studies
	1,666,323	HealthSouth		64,086,783
		Inpatient Rehabilitation Facilities
	1,239,000	Envision Healthcare Holdings (a)		42,980,910
		Provider of Health Care Outsourcing Services
	2,746,200	Allscripts Healthcare Solutions (a)		35,068,974
		Health Care IT
	863,500	Castlight Health (a)(c)		10,102,950
		Provider of Cloud-based Software for Managing Health Care Costs
				226,228,242
		> Pharmaceuticals 1.1%
	4,845,000	Akorn (a)		175,389,000
		Developer, Manufacturer & Distributor of Specialty Generic Drugs
		> Medical Equipment & Devices 0.9%
	752,000	Abaxis		42,736,160
		Instruments & Tests for Vet & Medical Markets
	460,900	Sirona Dental Systems (a)		40,268,833
		Manufacturer of Dental Equipment
	1,255,500	Wright Medical Group (a)		33,735,285
		Leader in Foot & Ankle Replacement
	448,000	Align Technology (a)		25,047,680
		Invisalign System to Correct Malocclusion (Crooked Teeth)
				141,787,958
Health Care: Total				1,629,317,878
Other Industries 6.2%
		> Real Estate 3.7%
	2,000,000	Extra Space Storage		117,280,000
		Self Storage Facilities
	750,000	Federal Realty		100,095,000	��
		Shopping Centers
	2,450,000	EdR (b)		89,645,500
		Student Housing
	1,320,000	Post Properties		77,576,400
		Multifamily Properties
	325,000	Jones Lang LaSalle		48,727,250
		Real Estate Services
	170,000	Amerco		48,324,200
		North American Moving & Storage King
	1,293,750	DCT Industrial Trust		46,135,125
		Industrial Properties

See accompanying notes to financial statements.

Number of Shares			Value
		> Real Estate—continued
	2,150,000	Terreno Realty (b)	$	44,354,500
		Industrial Properties
	872,926	St. Joe (a)		16,053,109
		Florida Panhandle Landowner
	39,381	Deltic Timber		2,693,661
		Arkansas Land & Timber
				590,884,745
		> Transportation 1.8%
	2,650,000	Rush Enterprises, Class A (a)(b)		84,932,500
	550,000	Rush Enterprises, Class B (a)(b)		15,488,000
		Truck Sales & Service
	940,000	JB Hunt Transport Services		79,195,000
		Truck & Intermodal Carrier
	730,000	Kirby (a)		58,940,200
		Operator of U.S. (Jones Act) Liquid Tank Barges
	380,000	Genesee & Wyoming (a)		34,169,600
		Short-line Operator
	496,024	Heartland Express		13,397,608
		Regional Trucker
				286,122,908
		> Regulated Utilities 0.7%
	1,600,000	Northeast Utilities		85,632,000
		Regulated Electric Utility
	500,000	Wisconsin Energy		26,370,000
		Wisconsin Utility
				112,002,000
Other Industries: Total				989,009,653
Energy & Minerals 4.1%
		> Oil & Gas Producers 1.8%
	717,000	Energen Corporation		45,715,920
		Oil & Gas Producer with Natural Gas Utility
	1,849,600	Rosetta Resources (a)		41,264,576
		Oil & Gas Producer Exploring in Texas
	926,000	Carrizo Oil & Gas (a)		38,521,600
		Oil & Gas Producer
	632,000	Range Resources		33,780,400
		Oil & Gas Producer
	778,000	SM Energy		30,015,240
		Oil & Gas Producer
	501,000	PDC Energy (a)		20,676,270
		Oil & Gas Producer in the U.S.
	281,000	Clayton Williams (a)		17,927,800
		Oil & Gas Producer
	1,210,000	WPX Energy (a)		14,072,300
		Oil & Gas Produced in the U.S. & Argentina
	1,800,000	Pacific Rubiales Energy (Colombia) (c)		11,139,611
		Oil Production & Exploration in Colombia
	1,400,000	DeeThree Exploration (Canada) (a)		6,157,686
		Canadian Oil & Gas Producer

Number of Shares			Value
	42,000,000	Petroamerica Oil (Colombia) (a)	$	5,061,112
		Oil Exploration & Production in Colombia
	203,000	Bonanza Creek Energy (a)		4,872,000
		Oil & Gas Producer in Western U.S.
	67,500,000	Petromanas (Canada) (a)(b)(c)		3,485,970
		Exploring for Oil in Albania
	24,115,500	Canadian Overseas Petroleum (Canada) (a)(b)		2,075,702
	8,400,000	Canadian Overseas Petroleum (Canada) (a)(b)(d)		686,865
		Oil & Gas Exploration Offshore West Africa
	28,962,000	ShaMaran Petroleum (Iraq) (a)		2,742,142
		Oil Exploration & Production in Kurdistan
	2,600,000	Petrodorado Energy (Colombia) (a)(b)		302,117
		Oil & Gas Exploration & Production in Colombia, Peru & Paraguay
				278,497,311
		> Oil Services 1.3%
	1,797,579	ShawCor (Canada)		65,602,814
		Oil & Gas Pipeline Products
	1,613,000	Hornbeck Offshore (a)		40,276,610
		Supply Vessel Operator in U.S. Gulf of Mexico
	964,000	Chart Industries (a)		32,968,800
		Manufacturer of Natural Gas Processing/Storage Equipment
	780,000	Gulfport Energy (a)		32,557,200
		Oil & Gas Producer Focused on Utica Shale in Ohio
	370,000	FMC Technologies (a)		17,330,800
		Oil & Gas Well Head Manufacturer
	289,000	Rowan		6,739,480
		Contract Offshore Driller
	2,601,900	Horizon North Logistics (Canada) (c)		5,912,391
		Provider of Diversified Oil Services in Northern Canada
	214,100	Black Diamond Group (Canada)		2,347,766
		Provider of Accommodations/ Equipment for Oil Sands Development
				203,735,861
		> Mining 0.9%
	505,000	Core Labs (Netherlands) (c)		60,771,700
		Oil & Gas Reservoir Consulting
	3,500,000	Alamos Gold (Canada)		25,004,304
		Gold Mining
	6,347,100	Kirkland Lake Gold (Canada) (a)(b)(c)		18,301,588
		Gold Mining

See accompanying notes to financial statements.

Columbia Acorn® Fund

Statement of Investments, continued

Number of Shares			Value
		> Mining—continued
	599,000	US Silica (c)	$	15,388,310
		Provider of Frac Sand & Industrial Sand in U.S.
	9,014,700	Argonaut Gold (Canada) (a)(b)(c)		14,199,433
		Gold & Silver Mining
	7,103,513	Allied Nevada Gold (a)(b)(c)		6,180,056
		Gold & Silver Mining
	3,412,300	Silvercrest Mines (a)		4,170,654
		Gold & Silver Mining
	3,000,000	Kaminak Gold (a)		1,988,294
		Exploration Stage Canadian Gold Miner
	2,800,000	Alexco Resource (a)		1,454,880
		Mining, Exploration & Environmental Services
				147,459,219
		> Agricultural Commodities 0.1%
	1,306,818	Union Agriculture Group (Uruguay) (a)(d)(e)		11,931,248
		Farmland Operator in Uruguay
		> Alternative Energy —%
	5,000,000	RGS Energy (a)(b)(c)		2,415,500
		U.S. Residential & Commercial Solar Systems Installer
	1,000,000	Synthesis Energy Systems (China) (a)		947,000
		Owner/Operator of Gasification Plants/Technology Licenses
				3,362,500
Energy & Minerals: Total				644,986,139
Total Equities: 97.7% (Cost: $8,478,158,225)				15,568,663,720	(f)

Number of Shares			Value
Short-Term Investments 2.5%
	280,000,000	JPMorgan U.S. Government Money Market Fund, IM Shares (7 day yield of 0.01%)	$	280,000,000
	128,802,371	JPMorgan U.S. Government Money Market Fund, Agency Shares (7 day yield of 0.01%)		128,802,371
Total Short-Term Investments: 2.5% (Cost: $408,802,371)				408,802,371
Securities Lending Collateral 3.4%
	534,041,419	Dreyfus Government Cash Management Fund, Institutional Shares (7 day yield of 0.01%) (g)		534,041,419
Total Securities Lending Collateral: 3.4% (Cost: $534,041,419)				534,041,419
Total Investments: 103.6% (Cost: $9,421,002,015)(h)				16,511,507,510
Obligation to Return Collateral for Securities Loaned: (3.4)%				(534,041,419	)
Cash and Other Assets Less Liabilities: (0.2)%				(42,890,066	)
Net Assets: 100.0%			$	15,934,576,025

ADR - American Depositary Receipts

> Notes to Statement of Investments

(a) Non-income producing security.

(b) An affiliated person of the Fund, as defined in the Investment Company Act of 1940, may include any company in which the Fund owns five percent or more of its outstanding voting shares. Holdings and transactions in these affiliated companies during the year ended December 31, 2014, are as follows:

Security	Balance of Shares Held 12/31/13		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/14		Value		Dividend
Mettler-Toledo International (1)		1,475,000		-		313,000		1,162,000	$	351,458,520	$	-
Donaldson		8,400,000		-		448,000		7,952,000		307,185,760		5,304,300
Cepheid		6,170,000		246,000		1,065,200		5,350,800		289,692,312		-
Nordson		3,400,000		-		270,000		3,130,000		244,014,800		2,680,180
Synageva BioPharma		2,392,000		181,000		153,791		2,419,209		224,478,403		-
Informatica (1)		5,500,000		550,000		850,000		5,200,000		198,302,000		-
Moog		3,230,000		-		774,000		2,456,000		181,817,680		-
Akorn (1)		5,417,981		881,485		1,454,466		4,845,000		175,389,000		-
HEICO		3,828,750		-		202,000		3,626,750		171,762,880		483,598
Generac		3,113,000		887,000		368,000		3,632,000		169,832,320		-
Associated Banc-Corp		9,000,000		-		-		9,000,000		167,670,000		3,330,000
iGATE (1)		4,150,000		15,083		565,083		3,600,000		142,128,000		-

See accompanying notes to financial statements.

> Notes to Statement of Investments

Security	Balance of Shares Held 12/31/13		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/14		Value		Dividend
Rush Enterprises		3,650,000		-		450,000		3,200,000	$	100,420,500	$	-
EdR (2)		2,450,000		-		-		2,450,000		89,645,500		2,665,110
Globalstar (1)		25,500,000		7,150,000		1,650,000		31,000,000		85,250,000		-
MB Financial (1)		2,860,000		-		280,000		2,580,000		84,778,800		1,448,000
Drew Industries		1,780,000		-		170,000		1,610,000		82,222,700		-
Bankrate		200,000		6,100,300		-		6,300,300		78,312,729		-
SPS Commerce		900,000		580,000		150,000		1,330,000		75,317,900		-
ESCO Technologies		2,300,000		-		352,000		1,948,000		71,881,200		698,640
Knoll		3,669,000		-		303,000		3,366,000		71,258,220		1,724,760
Virtusa		1,985,000		-		327,000		1,658,000		69,088,860		-
World Acceptance		850,000		-		41,657		808,343		64,222,852		-
Navigant Consulting		4,025,000		103,523		-		4,128,523		63,455,399		-
McGrath Rentcorp		2,150,000		-		570,000		1,580,000		56,658,800		2,022,750
Vonage		-		14,044,775		-		14,044,775		53,510,593		-
Ultragenyx Pharmaceutical (1)(2)		1,151,982		472,707		459,715		1,164,974		51,119,059		253,930
Thermon		1,065,000		875,094		-		1,940,094		46,930,874		-
Terreno Realty		2,020,931		129,069		-		2,150,000		44,354,500		1,225,500
Cavco Industries		460,000		40,000		-		500,000		39,635,000		-
Popeyes Louisiana Kitchen (1)		2,000,000		-		1,300,000		700,000		39,389,000		-
Boulder Brands		2,886,552		1,500,000		902,552		3,484,000		38,533,040		-
Sarepta Therapeutics		2,050,000		887,000		413,100		2,523,900		36,520,833		-
Allscripts Healthcare Solutions (1)		9,905,000		-		7,158,800		2,746,200		35,068,974		-
CAI International		1,500,000		-		-		1,500,000		34,800,000		-
PGT		738,564		2,853,636		-		3,592,200		34,592,886		-
InContact		3,740,596		404		-		3,741,000		32,883,390		-
First Busey (1)		4,841,882		-		513,382		4,328,500		28,178,535		919,958
Blackhawk Network (1)		900,000		-		200,000		700,000		26,383,000		-
GTT Communications		-		1,950,000		-		1,950,000		25,798,500		-
Hackett Group		3,274,000		-		370,281		2,903,719		25,523,690		369,754
E2Open		610,000		1,965,000		-		2,575,000		24,745,750		-
Insperity (1)		1,400,000		-		685,000		715,000		24,231,350		2,288,240
Boingo Wireless		2,500,000		300,000		-		2,800,000		21,476,000		-
Amber Road		-		2,000,000		-		2,000,000		20,440,000		-
Marlin Business Services		1,091,000		-		188,790		902,210		18,522,371		489,171
Kirkland Lake Gold		4,900,000		1,447,100		-		6,347,100		18,301,588		-
Gaiam		1,500,000		600,000		-		2,100,000		14,973,000		-
Argonaut Gold		-		9,014,700		-		9,014,700		14,199,433		-
Liquidity Services		900,000		700,000		-		1,600,000		13,072,000		-
Rubicon Technology		-		2,500,000		-		2,500,000		11,425,000		-
Audience		-		2,150,000		-		2,150,000		9,460,000		-
Tangoe (1)		2,100,000		-		1,458,048		641,952		8,364,635		-
Towerstream		3,319,900		680,100		-		4,000,000		7,400,000		-
Exa (1)		1,000,000		-		445,609		554,391		6,530,726		-
Allied Nevada Gold		2,000,000		5,103,513		-		7,103,513		6,180,056		-
Petroamerica Oil (1)		35,000,000		7,000,000		-		42,000,000		5,061,112		-
Petromanas		51,359,500		16,140,500		-		67,500,000		3,485,970		-
Canadian Overseas Petroleum		19,471,000		13,044,500		-		32,515,500		2,762,567		-
RGS Energy		2,600,000		2,400,000		-		5,000,000		2,415,500		-
GLG Life Tech (1)		1,665,270		-		-		1,665,270		458,673		-
Petrodorado Energy (2)		2,600,000		-		-		2,600,000		302,117		-
Acorn Energy (1)		1,161,957		-		1,161,957		-		-		-
Alimera Sciences (1)		2,040,000		-		2,040,000		-		-		-
Bally Technologies (1)		3,105,000		-		3,105,000		-		-		-
Coresite Realty (1)		1,170,000		-		1,170,000		-		-		1,139,962
Duluth Metals (1)		7,025,500		-		7,025,500		-		-		-
Dupont Fabros Technology (1)		3,625,000		-		3,625,000		-		-		1,128,750
H & E Equipment Services (1)		2,508,816		-		2,508,816		-		-		-
II-VI (1)		3,640,000		-		3,640,000		-		-		-

See accompanying notes to financial statements.

Columbia Acorn® Fund

Statement of Investments, continued

> Notes to Statement of Investments

Security	Balance of Shares Held 12/31/13		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/14		Value		Dividend
Pier 1 Imports (1)		7,185,000		-		7,185,000		-	$	-	$	939,780
Simplicity Bancorp (1)		452,146		-		452,146		-		-		72,577
tw telecom (1)		9,500,000		-		9,500,000		-		-		-
Total of Affiliated Transactions		320,360,327		104,492,489		66,265,893		358,586,923	$	4,443,274,857	$	29,184,960

(1) At December 31, 2014, the Fund owned less than five percent of the company's outstanding voting shares.

(2) Includes the effects of a stock split.

The aggregate cost and value of these companies at December 31, 2014, was $1,936,450,819 and $3,181,183,473, respectively. Investments in affiliated companies represented 19.96% of the Fund's total net assets at December 31, 2014.

(c) All or a portion of this security was on loan at December 31, 2014. The total market value of securities on loan at December 31, 2014 was $517,888,630.

(d) Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued at fair value determined in good faith under consistently applied procedures established by the Fund's Board of Trustees. At December 31, 2014, the market value of these securities amounted to $13,147,231, which represented 0.08% of total net assets. Additional information on these securities is as follows:

Security	Acquisition Dates	Shares/Units		Cost		Value
Union Agriculture Group	12/8/10-6/27/12		1,306,818	$	15,000,000	$	11,931,248
Canadian Overseas Petroleum	11/24/10		8,400,000		3,591,152		686,865
MicroDose Therapeutx Contingent Value Rights	8/14/13		359,944		-		529,118
				$	18,591,152	$	13,147,231

(e) Illiquid security.

(f) On December 31, 2014, the market value of foreign securities represented 4.20% of total net assets. The Fund's foreign portfolio was diversified as follows:

Country	Value		Percentage of Net Assets
Canada	$	217,238,937		1.36
Netherlands		125,338,953		0.79
India		74,874,429		0.47
Sweden		50,037,952		0.31
South Africa		44,009,075		0.28
Denmark		38,198,138		0.24
France		37,902,569		0.24
Israel		37,686,600		0.24
Colombia		16,502,840		0.10
Uruguay		11,931,248		0.07
Spain		5,671,933		0.04
United Kingdom		5,412,491		0.03
Iraq		2,742,142		0.02
China		947,000		0.01
Total Foreign Portfolio	$	668,494,307		4.20

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

(h) At December 31, 2014, for federal income tax purposes, the cost of investments was $9,429,781,549 and net unrealized appreciation was $7,081,725,961 consisting of gross unrealized appreciation of $7,688,655,656 and gross unrealized depreciation of $606,929,695.

Fair Value Measurements

Various inputs are used in determining the value of the Fund's investments, following the input prioritization hierarchy established by accounting principles generally accepted in the United States of America (GAAP). These inputs are summarized in the three broad levels listed below:

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

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

• Level 3 – prices determined using significant unobservable inputs where quoted prices or observable inputs are unavailable or less reliable (including management's own assumptions about the factors market participants would use in pricing an investment)

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

See accompanying notes to financial statements.

> Notes to Statement of Investments

Examples of the types of securities in which the Fund would typically invest and how they are classified within this 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, forward foreign currency exchange contracts and short-term investments valued at amortized cost. Additionally, securities fair valued by the Valuation Committee (the Committee) of the Fund's Board of Trustees (the Board) that rely on significant observable inputs are also included in Level 2. Typical Level 3 securities include any security fair valued by the Committee that relies on significant unobservable inputs.

Under the direction of the Board, the Committee is responsible for overseeing the valuation procedures approved by the Board.

The Committee meets as necessary, and no less frequently than quarterly, to determine fair values for securities for which market quotations are not readily available or for which the investment manager believes that available market quotations are unreliable, to review the appropriateness of the Trust's Portfolio Pricing Policy and the pricing procedures of the investment manager (the Policies), and to review the continuing appropriateness of the current value of any security subject to the Policies. The Policies address, among other things: circumstances under which market quotations will be deemed readily available; selection of third party pricing vendors; appropriate pricing methodologies; events that require fair valuation and fair value techniques; circumstances under which securities will be deemed to pose a potential for stale pricing, including when securities are illiquid, restricted, or in default; and certain delegations of authority to determine fair values to the Fund's investment manager. The Committee may also meet to discuss additional valuation matters, which may include review of back-testing results, review of time-sensitive information or approval of other valuation related actions, and to review the appropriateness of the Policies.

For investments categorized as Level 3, the significant unobservable inputs used in the fair value measurement of the Funds' securities may include: (i) data specific to the issuer or comparable issuers, (ii) general market or specific sector news and (iii) quoted prices and specific or similar security transactions. The Committee considers this data and any changes from prior periods in order to assess the reasonableness of observable and unobservable inputs, any assumptions or internal models used to value those securities and changes in fair value. Significant changes in any of these factors could result in lower or higher fair value measurements. Various factors impact the frequency of monitoring (which may occur as often as daily), however the Committee may determine that changes to inputs, assumptions and models are not required with the same frequency.

The following table summarizes the inputs used, as of December 31, 2014, 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
Information	$	4,250,272,149	$	88,488,372	$	-	$	4,338,760,521
Industrial Goods & Services		3,695,383,521		140,667,960		-		3,836,051,481
Consumer Goods & Services		2,120,353,406		5,671,933		-		2,126,025,339
Finance		1,960,503,634		44,009,075		-		2,004,512,709
Health Care		1,628,788,760		-		529,118		1,629,317,878
Other Industries		989,009,653		-		-		989,009,653
Energy & Minerals		632,368,026		686,865		11,931,248		644,986,139
Total Equities		15,276,679,149		279,524,205		12,460,366		15,568,663,720
Total Short-Term Investments		408,802,371		-		-		408,802,371
Total Securities Lending Collateral		534,041,419		-		-		534,041,419
Total Investments	$	16,219,522,939	$	279,524,205	$	12,460,366	$	16,511,507,510

The Fund's assets assigned to the Level 2 input category are generally valued using a market approach, in which a security's value is determined through its correlation to prices and information from observable market transactions for similar or identical assets. Foreign equities are generally valued at the last sale price on the foreign exchange or market on which they trade. The Fund may use a statistical fair valuation model, in accordance with the policy adopted by the Board, provided by an independent third party to value securities principally traded in foreign markets in order to adjust for possible stale pricing that may occur between the close of the foreign exchanges and the time for valuation. These models take into account available market data including intraday index, ADR, and ETF movements. Securities acquired via private placement that have a holding period or an extended settlement period are valued at a discount to the same shares that are trading freely on the market. These discounts are determined by the investment manager's experience with similar securities or situations. Factors may include, but are not limited to, trade volume, shares outstanding and stock price.

The following table shows transfers between Level 1 and Level 3 of the fair value hierarchy:

Transfers In				Transfers Out
Level 1		Level 3		Level 1		Level 3
$	14,371,342	$	-	$	-	$	14,371,342

There were no transfers of financial assets between levels 1 and 2 during the period. Transfers in and/or out of Level 3 are determined based on the fair value at the beginning of the period for security positions held throughout the period.

Financial assets were transferred from Level 3 to Level 1 as resale restrictions no longer apply.

See accompanying notes to financial statements.

Columbia Acorn® Fund

Statement of Investments, continued

> Notes to Statement of Investments

The Fund does not hold any significant investments (greater than one percent of net assets) categorized as Level 3.

Certain securities classified as Level 3 are valued at fair value, using a market approach, as determined in good faith under consistently applied procedures established by and under the general supervision of the Board. To determine fair value for these securities, for which no market exists, the Committee utilizes the valuation technique it deems most appropriate in the circumstances, using some unobservable inputs, which may include, but are not limited to estimated earnings of the company and the position of the security within the company's capital structure. The Committee also may use some observable inputs, which may include, but are not limited to, trades of similar securities and market multiples derived from a set of comparable companies. Significant increases or decreases to any of these inputs could result in a significantly lower or higher fair value measurement.

See accompanying notes to financial statements.

Columbia Acorn International®

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	9/30/14		12/31/14
Purchases
Asia
> Japan
Benesse		1,105,800		1,301,200
Ezaki Glico		269,000		746,500
Hamamatsu Photonics		527,500		650,800
NGK Insulators		1,200,000		1,600,000
NGK Spark Plug		1,010,000		1,170,000
Nippon Kayaku		3,196,000		3,260,000
Otsuka		0		419,300
Rohto Pharmaceutical		1,668,900		1,942,000
Ushio		2,900,000		3,850,800
> Taiwan
Advantech		3,078,687		3,118,686
Largan Precision		336,000		364,000
PChome Online		2,139,680		2,300,000
President Chain Store		5,250,000		7,306,000
St. Shine Optical		2,001,000		2,081,000
Vanguard International Semiconductor		3,927,000		14,329,000
> Korea
Cheil Industries		0		122,726
Cheil Worldwide		0		1,187,900
Nongshim		0		94,000
> China
NewOcean Energy		29,072,000		32,790,000
> Singapore
Mapletree Commercial Trust		40,564,179		53,724,268
Mapletree Logistics Trust		19,349,750		20,865,750
Singapore Exchange		5,803,000		6,596,000
> Hong Kong
Lifestyle International		10,000,000		13,120,000
Mapletree Greater China Commercial Trust		50,000,000		52,849,000
> Indonesia
Link Net		0		37,000,000
> Philippines
Puregold Price Club		32,706,600		35,000,000
Europe
> United Kingdom
Aggreko		975,602		1,300,000
Assura		20,900,000		32,700,000
Babcock International		3,590,000		4,000,000
Connect Group		11,184,000		14,379,428
Halma		2,483,322		2,725,000
Rightmove		1,134,000		1,338,000

	Number of Shares
	9/30/14		12/31/14
> Germany
Elringklinger		595,000		745,000
MTU Aero Engines		365,000		465,000
> France
Eutelsat		767,000		798,001
> Netherlands
Brunel		764,253		1,140,000
> Spain
Prosegur		5,042,000		6,564,000
> Italy
Pirelli		1,959,000		2,787,000
Other Countries
> Australia
Challenger Financial		11,515,000		12,550,000
Estia Health		0		5,000,000
Spotless		37,550,000		42,700,000
> Canada
Rona		1,656,569		2,108,517
> New Zealand
Ryman Healthcare		3,738,000		4,011,000
Latin America
> Mexico
Grupo Aeroportuario del Sureste - ADR		200,000		252,000
> Brazil
Odontoprev		6,000,000		6,487,000

See accompanying notes to financial statements.

Columbia Acorn International®

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

	Number of Shares
	9/30/14		12/31/14
Sales
Asia
> Japan
Aeon Mall		2,255,000		2,004,900
Aica Kogyo		1,538,500		1,246,000
Asahi Diamond Industrial		2,100,000		1,914,500
Glory		1,555,000		1,430,000
Hoshizaki Electric		500,000		420,000
Japan Airport Terminal		1,090,000		960,000
Kansai Paint		4,784,600		2,978,600
Lifenet Insurance		1,191,200		488,700
Makita		630,000		600,000
Nabtesco		1,440,000		1,110,000
Nihon Parkerizing		1,222,080		1,104,980
OBIC		838,000		688,000
Omron		603,000		462,000
Rinnai		355,000		309,000
Suruga Bank		1,560,000		1,470,000
Wacom		3,885,400		0
> Taiwan
Delta Electronics		6,729,000		3,761,000
Hermes Microvision		349,750		174,750
Lite-On Technology		11,470,881		5,594,881
> Korea
CJ Corp		316,943		245,944
KEPCO Plant Service & Engineering		294,940		0
KT&G		507,000		349,317
Soulbrain		279,090		86,274
> China
Biostime		3,850,000		0
Jumei International - ADR		580,600		0
> Singapore
CDL Hospitality Trust		20,000,000		17,742,000
Petra Foods		8,900,000		8,500,000
Super Group		3,802,000		0
> Hong Kong
Kingboard Chemicals		5,175,500		4,358,000
Melco Crown Entertainment - ADR		2,178,000		1,800,000
Melco International		16,798,000		15,000,000
MGM China Holdings		8,320,000		7,247,000
Sa Sa International		47,509,000		33,757,000
Vitasoy International		10,000,000		5,818,000
> Indonesia
Ace Indonesia		400,000,000		324,290,001
Archipelago Resources		31,764,600		0
Matahari Department Store		20,000,000		19,000,000
Surya Citra Media		74,536,300		54,535,800

	Number of Shares
	9/30/14		12/31/14
> Philippines
Security Bank		5,555,150		5,000,000
Universal Robina		3,743,130		2,114,550
> Thailand
Robinson Department Store		15,703,000		14,485,000
> Malaysia
Aeon		24,006,700		22,609,800
7-Eleven Malaysia Holdings		51,801,200		46,980,000
Europe
> United Kingdom
Jardine Lloyd Thompson Group		4,365,635		3,950,000
Shaftesbury		3,066,000		1,480,000
Telecity		2,210,000		0
Whitbread		606,940		470,940
> Germany
TAG Immobilien		406,158		0
> Sweden
Hexagon		2,308,522		2,168,522
> Netherlands
Core Labs		143,395		114,395
> Switzerland
Sika		16,300		0
> Finland
Vacon		1,226,866		0
> Iceland
Marel		35,982,499		0
Other Countries
> South Africa
Coronation Fund Managers		14,021,217		13,858,792
Massmart Holdings		2,230,504		0
> Australia
Amcor		7,030,000		6,725,000
Domino's Pizza Enterprises		3,500,000		2,978,993
IAG		14,000,000		10,600,000
MMA Offshore		12,820,287		10,912,000
SAI Global		3,900,000		0
> United States
FMC Technologies		601,213		168,213
Latin America
> Mexico
Genomma Lab International		15,347,000		10,184,000
> Brazil
Beadell Resources		58,937,078		37,336,982
Localiza Rent A Car		4,000,000		2,802,000

See accompanying notes to financial statements.

Columbia Acorn International®

Statement of Investments, December 31, 2014

Number of Shares			Value
			Equities: 94.1%
Asia 42.8%
		> Japan 19.3%
	2,978,600	Kansai Paint	$	46,144,399
		Paint Producer in Japan, India, China & Southeast Asia
	30,000	Orix JREIT		42,188,637
		Diversified REIT
	3,260,000	Nippon Kayaku		40,543,242
		Functional Chemicals, Pharmaceuticals & Auto Safety Systems
	3,850,800	Ushio		40,102,439
		Industrial Light Sources
	1,050,000	FamilyMart		39,547,023
		Convenience Store Operator
	1,301,200	Benesse		38,610,435
		Education Service Provider
	1,430,000	Glory		38,525,770
		Currency Handling Systems & Related Equipment
	960,000	Japan Airport Terminal		37,751,039
		Airport Terminal Operator at Haneda
	1,170,000	NGK Spark Plug		35,550,945
		Automobile Parts
	2,004,900	Aeon Mall		35,528,774
		Suburban Shopping Mall Developer, Owner & Operator
	6,149	Kenedix Office Investment		34,804,239
		Tokyo Mid-size Office REIT
	434,400	Disco		34,744,418
		Semiconductor Dicing & Grinding Equipment
	1,600,000	NGK Insulators		32,797,283
		Ceramic Products for Auto, Power & Electronics
	960,000	Misumi Group		31,656,187
		Industrial Components Distributor
	2,150,000	Park24		31,650,928
		Parking Lot Operator
	650,800	Hamamatsu Photonics		30,980,048
		Optical Sensors for Medical & Industrial Applications
	4,872,000	NOF		30,785,305
		Specialty Chemicals, Life Science & Rocket Fuels
	264,400	Hirose Electric		30,676,490
		Electrical Connectors
	750,000	Kintetsu World Express		28,778,874
		Airfreight Logistics
	970,000	Nippon Paint Holdings		28,108,662
		Paints for Automotive, Decorative & Industrial Usage
	1,402,000	Tamron (a)		27,797,869
		Camera Lenses
	1,129,000	Ariake Japan		27,452,191
		Commercial Soup & Sauce Extracts
	1,580,000	Daiseki		27,297,290
		Waste Disposal & Recycling

Number of Shares			Value
	643,000	Nakanishi	$	27,297,114
		Dental Tools & Machinery
	600,000	Makita		27,037,193
		Power Tools
	1,470,000	Suruga Bank		27,014,176
		Regional Bank
	208,000	Shimano		26,940,511
		Manufacturer of Bicycle Components & Fishing Tackle
	1,110,000	Nabtesco		26,827,201
		Machinery Components
	486,600	Santen Pharmaceutical		26,196,007
		Specialty Pharma (Ophthalmic Medicine)
	746,500	Ezaki Glico		26,095,707
		Confectionary, Ice Cream & Dairy Products
	1,600,000	OSG		25,819,113
		Consumable Cutting Tools
	8,340,000	Aozora Bank		25,816,838
		Commercial Bank
	1,246,000	Aica Kogyo		25,731,219
		Laminated Sheets, Building Materials & Chemical Adhesives
	792,900	Toyo Suisan Kaisha		25,530,504
		Instant Noodles & Processed Foods
	2,736,000	Moshi Moshi Hotline		25,252,086
		Call Center Operator
	1,104,980	Nihon Parkerizing		25,210,166
		Metal Surface Treatment Chemicals & Processing Service
	1,942,000	Rohto Pharmaceutical		24,263,266
		Pharmaceutical, Health & Beauty Products
	1,107,000	Stanley Electric		23,903,959
		Automobile Lighting & LED Equipment
	1,205,000	Aeon Financial Service		23,799,858
		Diversified Consumer-related Finance Company in Japan
	2,000,000	Toto		23,265,410
		Toilets & Bathroom Fittings
	930,000	JIN (b)		23,236,639
		Eyeglasses Retailer
	1,600,000	Doshisha		22,592,036
		Consumer Goods Wholesaler
	688,000	OBIC		22,325,402
		Computer Software
	4,800	Industrial & Infrastructure Fund		22,205,532
		Industrial REIT in Japan
	309,000	Rinnai		20,762,389
		Gas Appliances for Home & Commercial Use
	462,000	Omron		20,667,797
		Electric Components for Factory Automation
	420,000	Hoshizaki Electric		20,238,938
		Commercial Kitchen Equipment
	835,000	Icom (a)		20,090,612
		Two-way Radio Communication Equipment

See accompanying notes to financial statements.

Columbia Acorn International®

Statement of Investments, continued

Number of Shares			Value
		> Japan—continued
	1,914,500	Asahi Diamond Industrial	$	20,016,215
		Consumable Diamond Tools
	8,150	Japan Retail Fund		17,223,263
		Retail REIT in Japan
	255,800	Hikari Tsushin		15,558,892
		Office IT/Mobiles/Insurance Distribution
	571,080	Milbon		15,546,925
		Hair Products for Salons
	419,300	Otsuka		13,295,353
		One-stop IT Services & Office Supplies Provider
	575,600	MonotaRO (b)		11,597,760
		Online Maintenance, Repair and Operations Goods Distributor in Japan
	488,700	Lifenet Insurance (b)(c)		1,324,310
		Online Life Insurance Company in Japan
				1,494,704,878
		> Taiwan 4.2%
	7,306,000	President Chain Store		56,430,258
		Taiwanese Convenience Chain Store Operator
	2,081,000	St. Shine Optical		33,950,792
		Disposable Contact Lens Original Equipment Manufacturer
	5,410,000	Novatek Microelectronics		30,231,615
		Display Related Integrated Circuit Designer
	12,570,000	Far EasTone Telecom		28,958,139
		Taiwanese Mobile Operator
	364,000	Largan Precision		27,247,682
		Mobile Device Camera Lenses & Modules
	2,300,000	PChome Online		24,692,759
		Taiwanese Internet Retail Company
	14,329,000	Vanguard International Semiconductor		23,447,165
		Semiconductor Foundry
	3,118,686	Advantech		22,895,443
		Industrial PC & Components
	3,761,000	Delta Electronics		22,224,640
		Industrial Automation, Switching Power Supplies & Passive Components
	1,925,000	Ginko International		20,314,145
		Contact Lens Maker in China
	6,427,000	Chroma Ate		16,621,061
		Automatic Test Systems, Testing & Measurement Instruments
	174,750	Hermes Microvision		8,739,363
		E-beam Inspection Systems for Semiconductor Integrated Circuits
	5,594,881	Lite-On Technology		6,391,478
		Mobile Device, LED & PC Server Component Supplier
				322,144,540

Number of Shares			Value
		> Korea 3.1%
	245,944	CJ Corp	$	34,821,021
		Holding Company of Korean Consumer Conglomerate
	631,865	LS Industrial Systems		34,313,078
		Electrical & Automation Equipment
	349,317	KT&G		24,254,255
		Tobacco & Ginseng Products
	295,580	Coway		22,538,457
		Household Appliance Rentals
	94,000	Nongshim		21,564,561
		Instant Noodles, Snacks & Bottled Water
	974,261	Paradise		20,767,504
		Korean Casino Operator
	758,028	LF Corp		20,540,920
		Apparel Design & Retail
	1,187,900	Cheil Worldwide (c)		18,588,800
		Advertising
	122,726	Cheil Industries (c)		17,641,548
		Holding Company of Samsung Group
	591,876	Grand Korea Leisure		17,202,215
		'Foreigner Only' Casino Group in Korea
	86,274	Soulbrain		2,509,312
		Electronic Chemical Producer
				234,741,671
		> India 3.0%
	13,478,000	Zee Entertainment Enterprises		80,960,947
		Programmer of Pay Television Content
	3,423,265	Asian Paints		40,577,153
		Paint Company
	6,095,000	Adani Ports & Special Economic Zone		30,679,178
		Indian West Coast Shipping Port
	90,000	Bosch		27,794,506
		Automotive Parts
	2,085,000	United Breweries		27,486,487
		Brewer
	920,000	Colgate Palmolive India		25,983,244
		Consumer Products in Oral Care
				233,481,515
		> China 2.7%
	2,500,000	WuXi PharmaTech - ADR (c)		84,175,000
		Contract Research Organization Business in China
	83,100,000	Sihuan Pharmaceuticals		55,274,689
		Chinese Generic Drug Manufacturer
	407,570	BitAuto - ADR (b)(c)		28,697,004
		Automotive Information Website for Buyers & Dealers
	35,119,000	AMVIG Holdings		15,171,368
		Chinese Tobacco Packaging Material Supplier
	17,890,000	CIMC Enric		14,115,824
		Produces Tanks & Equipment to Supply Natural Gas & Liquefied Natural Gas

See accompanying notes to financial statements.

Number of Shares			Value
		> China—continued
	32,790,000	NewOcean Energy (b)	$	12,589,624
		Southern China Liquefied Petroleum Gas Distributor
				210,023,509
		> Singapore 2.6%
	53,724,268	Mapletree Commercial Trust		57,171,925
		Retail & Office Property Landlord
	6,596,000	Singapore Exchange		38,778,644
		Singapore Equity & Derivatives Market Operator
	8,500,000	Petra Foods		24,360,487
		Chocolate Manufacturer in South East Asia
	13,500,000	Ascendas REIT		24,215,667
		Industrial Property Landlord
	17,742,000	CDL Hospitality Trust		23,305,084
		Hotel Owner Operator
	20,865,750	Mapletree Logistics Trust		18,630,540
		Industrial Property Landlord
	15,000,000	Mapletree Industrial Trust		16,783,128
		Industrial Property Landlord
				203,245,475
		> Hong Kong 2.6%
	1,800,000	Melco Crown Entertainment - ADR		45,720,000
		Macau Casino Operator
	52,849,000	Mapletree Greater China Commercial Trust		37,823,829
		Retail & Office Property Landlord
	15,000,000	Melco International		32,836,786
		Macau Casino Operator
	13,120,000	Lifestyle International		27,611,614
		Mid- to High-end Department Store Operator in Hong Kong & China
	33,757,000	Sa Sa International (b)		23,549,236
		Cosmetics Retailer
	7,247,000	MGM China Holdings		18,298,055
		Macau Casino Operator
	5,818,000	Vitasoy International		8,413,794
		Hong Kong Soy Food Brand
	4,358,000	Kingboard Chemicals		7,317,616
		Paper & Glass Laminates, PCB, Specialty Chemicals & Properties
				201,570,930
		> Indonesia 1.7%
	33,000,000	Tower Bersama Infrastructure		25,809,845
		Communications Towers
	19,000,000	Matahari Department Store		22,894,258
		Department Store Chain in Indonesia
	324,290,000	Ace Indonesia		20,501,327
		Home Improvement Retailer
	220,150,800	Arwana Citramulia		15,391,849
		Ceramic Tiles for Home Decoration

Number of Shares			Value
	54,535,800	Surya Citra Media	$	15,390,151
		Free to Air TV Station in Indonesia
	37,000,000	Link Net (c)		14,698,426
		Fixed Broadband & CATV Service Provider
	5,600,000	Mayora Indah		9,448,261
		Consumer Branded Food Manufacturer
	49,000,000	MNC Skyvision		6,330,238
		Satellite Pay TV Operator in Indonesia
				130,464,355
		> Philippines 1.4%
	35,000,000	Puregold Price Club		29,981,495
		Supermarket Operator in the Philippines
	17,000,000	Robinsons Retail Holdings		28,768,792
		Multi-format Retailer in the Philippines
	78,170,000	Melco Crown (Philippines) Resorts (c)		23,642,949
		Integrated Resort Operator in Manila
	5,000,000	Security Bank		16,936,167
		Commercial Bank in the Philippines
	2,114,550	Universal Robina		9,219,198
		Branded Consumer Food Manufacturer in the Philippines
				108,548,601
		> Thailand 1.1%
	4,360,000	Airports of Thailand		37,146,292
		Airport Operator of Thailand
	107,731,500	Home Product Center		26,961,612
		Home Improvement Retailer
	14,485,000	Robinson Department Store		19,716,276
		Department Store Operator in Thailand
				83,824,180
		> Cambodia 0.6%
	60,000,000	Nagacorp		48,894,346
		Casino & Entertainment Complex in Cambodia
		> Malaysia 0.5%
	22,609,800	Aeon		20,307,312
		Shopping Center & Department Store Operator
	46,980,000	7-Eleven Malaysia Holdings (c)		20,154,440
		Exclusive 7-Eleven Franchisor for Malaysia
				40,461,752
Asia: Total				3,312,105,752

See accompanying notes to financial statements.

Columbia Acorn International®

Statement of Investments, continued

Number of Shares			Value
Europe 30.1%
		> United Kingdom 9.8%
	4,000,000	Babcock International	$	65,529,106
		Public Sector Outsourcer
	1,300,000	Spirax Sarco		57,871,906
		Steam Systems for Manufacturing & Processing Industries
	3,950,000	Jardine Lloyd Thompson Group		55,162,009
		International Business Insurance Broker
	2,430,000	WH Smith		50,815,383
		Newsprint, Books & General Stationery Retailer
	1,338,000	Rightmove		46,660,306
		Internet Real Estate Listings
	958,646	Fidessa Group		35,710,105
		Software for Financial Trading Systems
	470,940	Whitbread		34,852,503
		UK Hotelier & Coffee Shop
	14,379,428	Connect Group (a)		34,322,292
		Newspaper & Magazine Distributor
	4,550,000	Abcam		33,029,289
		Online Sales of Antibodies
	1,300,000	Aggreko		30,315,995
		Temporary Power & Temperature Control Services
	4,712,000	Ocado (b)(c)		29,166,860
		Online Grocery Retailer
	2,660,000	Domino's Pizza UK & Ireland		29,042,901
		Pizza Delivery in the UK, Ireland & Germany
	2,725,000	Halma		29,026,522
		Health & Safety Sensor Technology
	1,510,000	Smith and Nephew		27,229,143
		Medical Equipment & Supplies
	35,245,747	Cable and Wireless		27,091,940
		Telecommunications Services Provider in the Caribbean
	32,700,000	Assura		25,992,790
		Primary Health Care Property Developer
	6,534,800	Polypipe		25,003,689
		Manufacturer of Plastic Piping & Fittings
	3,277,885	Halfords		23,919,695
		UK Retailer for Leisure Goods & Auto Parts
	5,650,001	Elementis		22,902,088
		Specialty Chemicals
	2,834,000	PureCircle (c)		22,689,046
		Natural Sweeteners
	5,800,000	RPS Group		18,902,402
		Consultant Specializing in Energy, Water, Urban Planning, Health & Safety

Number of Shares			Value
	908,500	AVEVA	$	18,606,096
		Engineering Software
	1,480,000	Shaftesbury		17,909,543
		London Prime Retail REIT
				761,751,609
		> Germany 3.2%
	1,663,000	Wirecard		72,513,646
		Online Payment Processing & Risk Management
	130,000	Rational		40,733,523
		Commercial Ovens
	465,000	MTU Aero Engines		40,411,136
		Airplane Engine Components & Services
	795,000	NORMA Group		37,946,095
		Clamps for Automotive & Industrial Applications
	795,000	Aurelius		30,087,698
		European Turnaround Investor
	745,000	Elringklinger (b)		25,758,832
		Automobile Components
				247,450,930
		> Sweden 3.1%
	2,168,522	Hexagon		66,897,903
		Design, Measurement & Visualization Software & Equipment
	818,422	Unibet		51,705,503
		European Online Gaming Operator
	1,580,000	Swedish Match		49,508,540
		Swedish Snus
	3,255,024	Sweco		44,260,193
		Engineering Consultants
	1,044,000	Mekonomen		27,237,837
		Nordic Integrated Wholesaler/ Retailer of Automotive Parts & Service
				239,609,976
		> France 2.5%
	1,350,000	Neopost		77,014,552
		Postage Meter Machines
	146,000	Eurofins Scientific		37,266,825
		Food, Pharmaceuticals & Materials Screening & Testing
	798,001	Eutelsat		25,807,075
		Fixed Satellite Services
	163,400	Norbert Dentressangle		24,084,705
		European Logistics & Transport Group
	729,096	Saft		22,115,064
		Niche Battery Manufacturer
	1,831,204	Hi-Media (b)(c)		5,494,680
		Online Advertiser in Europe
				191,782,901
		> Netherlands 2.2%
	2,491,770	Aalberts Industries		73,484,903
		Flow Control & Heat Treatment
	790,670	Arcadis		23,714,268
		Engineering Consultants

See accompanying notes to financial statements.

Number of Shares			Value
		> Netherlands—continued
	404,124	Vopak	$	20,966,753
		Operator of Petroleum & Chemical Storage Terminals
	237,700	Gemalto		19,399,284
		Digital Security Solutions
	1,140,000	Brunel		18,667,725
		Temporary Specialist & Energy Staffing
	114,395	Core Labs (b)		13,766,294
		Oil & Gas Reservoir Consulting
				169,999,227
		> Spain 2.1%
	7,828,000	DIA		53,043,165
		Discount Retailer in Spain & Latin America
	794,000	Viscofan		42,126,681
		Sausage Casings Maker
	6,564,000	Prosegur		37,396,926
		Security Guards
	830,000	Bolsas y Mercados Españoles		32,146,208
		Spanish Stock Markets
				164,712,980
		> Switzerland 2.1%
	263,500	Partners Group		76,661,973
		Private Markets Asset Management
	179,000	Geberit		60,556,212
		Plumbing Supplies
	72,500	INFICON		22,478,500
		Gas Detection Instruments
				159,696,685
		> Denmark 1.8%
	1,315,800	Novozymes		55,386,707
		Industrial Enzymes
	1,932,063	SimCorp		51,011,579
		Software for Investment Managers
	709,000	Jyske Bank (c)		35,837,383
		Danish Bank
				142,235,669
		> Finland 1.1%
	7,766,000	Sponda		33,804,172
		Office, Retail & Logistics Properties
	1,669,000	Tikkurila		29,149,797
		Decorative & Industrial Paint in Scandinavia & Central & Eastern Europe
	711,000	Konecranes		20,331,177
		Manufacture & Service of Industrial Cranes & Port Handling Equipment
				83,285,146
		> Norway 0.9%
	2,613,864	Atea		27,004,901
		Nordic IT Hardware/Software Reseller & Installation Company

Number of Shares			Value
	3,784,000	Orkla	$	25,759,456
		Food & Brands, Aluminum, Chemicals Conglomerate
	1,321,000	Subsea 7		13,517,662
		Offshore Subsea Contractor
				66,282,019
		> Kazakhstan 0.6%
	5,143,000	Halyk Savings Bank of Kazakhstan - GDR		43,715,500
		Retail Bank & Insurer in Kazakhstan
		> Italy 0.5%
	2,787,000	Pirelli		37,589,393
		Global Tire Supplier
		> Belgium 0.2%
	516,965	EVS Broadcast Equipment		18,665,061
		Digital Live Mobile Production Software & Systems
Europe: Total				2,326,777,096
Other Countries 17.6%
		> South Africa 5.0%
	13,858,792	Coronation Fund Managers		137,151,874
		South African Fund Manager
	777,188	Naspers		100,533,337
		Media in Africa, China, Russia & other Emerging Markets
	20,179,300	Rand Merchant Insurance		71,278,010
		Directly Sold Property & Casualty Insurance; Holdings in other Insurers
	2,644,083	Mr. Price		53,486,851
		South African Retailer of Apparel, Household & Sporting Goods
	8,679,940	Northam Platinum (c)		27,360,931
		Platinum Mining in South Africa
				389,811,003
		> Australia 4.8%
	6,725,000	Amcor		73,990,708
		Global Leader in Flexible & Rigid Packaging
	12,550,000	Challenger Financial		66,295,863
		Annuity Provider in Australia
	42,700,000	Spotless (c)		66,143,743
		Facility Management & Catering Company
	2,978,993	Domino's Pizza Enterprises		60,655,383
		Domino's Pizza Operator in Australia & New Zealand
	10,600,000	IAG		53,821,673
		General Insurance Provider
	5,000,000	Estia Health (c)		19,348,676
		Residential Aged Care Operator
	2,196,850	Austbrokers		18,204,106
		Local Australian Small Business Insurance Broker
	10,912,000	MMA Offshore		10,939,429
		Support Vessels for Offshore Oil/Gas Industry
				369,399,581

See accompanying notes to financial statements.

Columbia Acorn International®

Statement of Investments, continued

Number of Shares			Value
		> Canada 4.2%
	862,772	CCL Industries	$	93,473,155
		Global Label Converter
	3,188,000	CAE		41,379,790
		Flight Simulator Equipment & Training Centers
	1,067,730	ShawCor		38,966,907
		Oil & Gas Pipeline Products
	490,200	Onex Capital		28,463,498
		Private Equity
	525,260	Ag Growth		25,548,668
		Manufacturer of Augers & Grain Handling Equipment
	2,108,517	Rona		25,135,962
		Canadian Home Improvement Retailer
	3,622,000	Canadian Energy Services & Technology (b)		19,796,609
		North American Drilling Fluids & Chemicals
	1,108,857	Baytex (b)		18,439,591
		Oil & Gas Producer in Canada
	2,168,377	DeeThree Exploration (c)		9,537,275
	1,130,000	DeeThree Exploration (c)(d)		4,870,730
		Canadian Oil & Gas Producer
	551,976	Black Diamond Group		6,052,827
		Provider of Accommodations/ Equipment for Oil Sands Development
	766,000	Trilogy Energy		5,215,235
		Oil & Gas Producer in Canada
	1,901,514	Horizon North Logistics (b)		4,320,879
		Provider of Diversified Oil Services in Northern Canada
				321,201,126
		> United States 1.9%
	1,272,297	Textainer Group Holdings (b)		43,665,233
		Top International Container Leaser
	350,000	Synageva BioPharma (b)(c)		32,476,500
		Biotech Focused on Orphan Diseases
	912,000	Bladex		27,451,200
		Latin American Trade Financing House
	685,900	Rowan		15,995,188
		Contract Offshore Driller
	634,500	Hornbeck Offshore (c)		15,843,465
		Supply Vessel Operator in U.S. Gulf of Mexico
	168,213	FMC Technologies (c)		7,879,097
		Oil & Gas Well Head Manufacturer
	225,000	Chart Industries (c)		7,695,000
		Manufacturer of Natural Gas Processing/Storage Equipment
				151,005,683

Number of Shares			Value
		> New Zealand 1.1%
	10,800,000	Auckland International Airport	$	35,536,052
		Auckland Airport Operator
	4,011,000	Ryman Healthcare		26,606,179
		Retirement Village Operator
	8,000,000	Sky City Entertainment		24,169,714
		Casino & Entertainment Complex
				86,311,945
		> Israel 0.6%
	791,000	Caesarstone		47,317,620
		Quartz Countertops
Other Countries: Total				1,365,046,958
Latin America 3.6%
		> Mexico 1.3%
	252,000	Grupo Aeroportuario del Sureste - ADR		33,223,680
		Mexican Airport Operator
	12,339,000	Qualitas		25,541,511
		Auto Insurer in Mexico & Central America
	2,200,000	Gruma		23,458,714
		Tortilla Producer & Distributor
	10,184,000	Genomma Lab International (c)		19,368,841
		Developer, Marketer & Distributor of Consumer Products
				101,592,746
		> Brazil 1.2%
	2,802,000	Localiza Rent A Car		37,641,795
		Car Rental
	6,487,000	Odontoprev		24,062,080
		Dental Insurance
	1,184,000	Linx		22,493,417
		Retail Management Software in Brazil
	37,336,982	Beadell Resources (b)(c)		6,762,258
		Gold Mining in Brazil
				90,959,550
		> Colombia 0.4%
	23,377,000	Isagen		29,165,918
		Colombian Electricity Provider
		> Guatemala 0.3%
	1,626,600	Tahoe Resources		22,611,112
		Silver Project in Guatemala
		> Chile 0.3%
	921,000	Sociedad Quimica y Minera de Chile - ADR		21,993,480
		Producer of Specialty Fertilizers, Lithium & Iodine
		> Uruguay 0.1%
	1,306,818	Union Agriculture Group (c)(d)(e)		11,931,248
		Farmland Operator in Uruguay
Latin America: Total				278,254,054
Total Equities: 94.1% (Cost: $5,764,507,118)				7,282,183,860	(f)

See accompanying notes to financial statements.

Number of Shares			Value
Short-Term Investments 5.2%
	220,000,000	JPMorgan U.S. Government Money Market Fund, IM Shares (7 day yield of 0.01%)	$	220,000,000
	180,694,890	JPMorgan U.S. Government Money Market Fund, Agency Shares (7 day yield of 0.01%)		180,694,890
Total Short-Term Investments: 5.2% (Cost: $400,694,890)				400,694,890

Number of Shares			Value
Securities Lending Collateral 1.4%
	105,532,274	Dreyfus Government Cash Management Fund, Institutional Shares (7 day yield of 0.01%) (g)	$	105,532,274
Total Securities Lending Collateral: 1.4% (Cost: $105,532,274)				105,532,274
Total Investments: 100.7% (Cost: $6,270,734,282)(h)				7,788,411,024
Obligation to Return Collateral for Securities Loaned: (1.4)%				(105,532,274	)
Cash and Other Assets Less Liabilities: 0.7%				50,599,385
Net Assets: 100.0%			$	7,733,478,135

ADR - American Depositary Receipts

GDR - Global Depositary Receipts

REIT - Real Estate Investment Trust

> Notes to Statement of Investments

(a) An affiliated person of the Fund, as defined in the Investment Company Act of 1940, may include any company in which the Fund owns five percent or more of its outstanding voting shares. Holdings and transactions in these affiliated companies during the year ended December 31, 2014, are as follows:

Security	Balance of Shares Held 12/31/13		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/14		Value		Dividend
Connect Group		10,944,000		4,353,749		918,321		14,379,428	$	34,322,292	$	1,907,037
Icom		835,000		-		-		835,000		20,090,612		237,621
Tamron		573,700		828,300		-		1,402,000		27,797,869		572,199
Beadell Resources (1)		58,937,078		-		21,600,096		37,336,982		6,762,258		-
Archipelago Resources (1)		31,764,600		-		31,764,600		-		-		-
Empresas Hites (1)		23,162,664		-		23,162,664		-		-		-
Total of Affiliated Transactions		126,217,042		5,182,049		77,445,681		53,953,410	$	88,973,031	$	2,716,857

(1) At December 31, 2014, the Fund owned less than five percent of the company's outstanding voting shares.

The aggregate cost and value of these companies at December 31, 2014, was $89,062,228 and $82,210,773, respectively. Investments in affiliated companies represented 1.06% of the Fund's total net assets at December 31, 2014.

(b) All or a portion of this security was on loan at December 31, 2014. The total market value of securities on loan at December 31, 2014 was $101,872,493.

(d) Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued at fair value determined in good faith under consistently applied procedures established by the Fund's Board of Trustees. At December 31, 2014, the market value of these securities amounted to $16,801,978, which represented 0.22% of total net assets. Additional information on these securities is as follows:

Security	Acquisition Dates	Shares/Units		Cost		Value
Union Agriculture Group	12/8/10-6/27/12		1,306,818	$	15,000,000	$	11,931,248
DeeThree Exploration	9/7/10		1,130,000		2,950,812		4,870,730
				$	17,950,812	$	16,801,978

(e) Illiquid security.

See accompanying notes to financial statements.

Columbia Acorn International®

Statement of Investments, continued

> Notes to Statement of Investments

(f) On December 31, 2014, the Fund's total equity investments were denominated in currencies as follows:

Currency	Value		Percentage of Net Assets
Japanese Yen	$	1,494,704,878		19.3
Euro		899,719,343		11.6
British Pound		761,751,609		9.8
U.S. Dollar		481,545,509		6.2
South African Rand		389,811,004		5.1
Other currencies less than 5% of total net assets		3,254,651,517		42.1
Total Equities	$	7,282,183,860		94.1

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

(h) At December 31, 2014, for federal income tax purposes, the cost of investments was $6,372,747,494 and net unrealized appreciation was $1,415,663,530 consisting of gross unrealized appreciation of $1,932,627,003 and gross unrealized depreciation of $516,963,473.

Fair Value Measurements

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

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

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

Under the direction of the Board, the Committee is responsible for overseeing the valuation procedures approved by the Board.

See accompanying notes to financial statements.

> Notes to Statement of Investments

The following table summarizes the inputs used, as of December 31, 2014, 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
Asia	$	158,592,004	$	3,153,513,748	$	-	$	3,312,105,752
Europe		13,766,294		2,313,010,802		-		2,326,777,096
Other Countries		514,653,699		850,393,259		-		1,365,046,958
Latin America		259,560,548		6,762,258		11,931,248		278,254,054
Total Equities		946,572,545		6,323,680,067		11,931,248		7,282,183,860
Total Short-Term Investments		400,694,890		-		-		400,694,890
Total Securities Lending Collateral		105,532,274		-		-		105,532,274
Total Investments	$	1,452,799,709	$	6,323,680,067	$	11,931,248	$	7,788,411,024

There were no transfers of financial assets between levels during the period.

The Fund does not hold any significant investments (greater than one percent of net assets) categorized as Level 3.

See accompanying notes to financial statements.

Columbia Acorn International®

Portfolio Diversification

At December 31, 2014, the Fund's portfolio investments as a percentage of net assets were diversified as follows:

	Value		Percentage of Net Assets
> Industrial Goods & Services
Industrial Materials & Specialty Chemicals	$	506,671,903		6.6
Machinery		482,299,182		6.2
Other Industrial Services		420,517,905		5.4
Outsourcing Services		187,737,500		2.4
Conglomerates		181,794,626		2.4
Electrical Components		180,672,150		2.3
Construction		85,559,900		1.1
Industrial Distribution		11,597,760		0.2
		2,056,850,926		26.6
> Consumer Goods & Services
Retail		619,547,181		8.0
Food & Beverage		317,354,170		4.1
Casinos & Gaming		283,237,071		3.7
Nondurables		176,906,442		2.3
Other Durable Goods		144,747,198		1.9
Restaurants		124,550,787		1.6
Consumer Goods Distribution		98,456,464		1.3
Other Consumer Services		50,150,071		0.6
Furniture & Textiles		47,317,620		0.6
Educational Services		38,610,435		0.5
Travel		37,641,795		0.5
Consumer Electronics		27,797,869		0.3
Apparel		20,540,920		0.3
		1,986,858,023		25.7
> Information
Business Software		217,044,503		2.8
Internet Related		175,890,647		2.3
Financial Processors		111,292,290		1.4
Semiconductors & Related Equipment		97,162,560		1.3
Computer Hardware & Related Equipment		89,575,906		1.2
Entertainment Programming		80,960,947		1.0
Instrumentation		76,627,631		1.0
Mobile Communications		74,858,596		1.0
Computer Services		40,300,254		0.5
Satellite Broadcasting & Services		32,137,313		0.4
Telecommunications Equipment		27,247,682		0.4
Telephone & Data Services		27,091,940		0.3
Business Information & Marketing Services		25,252,086		0.3
Advertising		24,083,480		0.3
TV Broadcasting		15,390,151		0.2
Cable TV		14,698,426		0.2
		1,129,614,412		14.6

	Value			Percentage of Net Assets
> Finance
Insurance	$	315,689,561			4.1
Brokerage & Money Management		213,813,848			2.8
Banks		200,571,122			2.6
Finance Companies		72,128,731			0.9
Financial Processors		32,146,208			0.4
		834,349,470			10.8
> Other Industries
Real Estate		407,587,124			5.3
Transportation		167,741,768			2.1
Regulated Utilities		29,165,918			0.4
		604,494,810			7.8
> Health Care
Pharmaceuticals		165,645,696			2.2
Medical Supplies		87,294,226			1.1
Medical Equipment & Devices		54,526,257			0.7
Health Care Services		45,954,855			0.6
Biotechnology & Drug Delivery		32,476,500			0.4
		385,897,534			5.0
> Energy & Minerals
Oil Services		130,067,633			1.7
Mining		70,500,595			0.9
Oil & Gas Producers		38,062,832			0.5
Oil Refining, Marketing & Distribution		33,556,377			0.4
Agricultural Commodities		11,931,248			0.1
		284,118,685			3.6
Total Equities:		7,282,183,860			94.1
Short-Term Investments:		400,694,890			5.2
Securities Lending Collateral:		105,532,274			1.4
Total Investments:		7,788,411,024			100.7
Obligation to Return Collateral for Securities Loaned:		(105,532,274	)		(1.4	)
Cash and Other Assets Less Liabilities:		50,599,385			0.7
Net Assets:	$	7,733,478,135			100.0

See accompanying notes to financial statements.

Columbia Acorn USA®

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	9/30/14		12/31/14
Purchases
Information
Fleetmatics		0		96,949
SPS Commerce		265,000		290,000
Textura		94,954		128,934
Virtusa		212,821		227,000
Consumer Goods & Services
Buffalo Wild Wings		0		18,500
Fox Factory Holding		10,005		102,184
Gentex		104,000		148,000
Michaels Stores		251,733		368,564
Finance
ViewPoint Financial		0		373,487
Health Care
Abaxis		40,482		61,200
Medidata Solutions		171,000		184,500
Sarepta Therapeutics		314,000		338,500
VWR		0		86,300
Wright Medical Group		106,000		200,300
Energy & Minerals
Bonanza Creek Energy		0		47,000
US Silica		0		49,000

	Number of Shares
	9/30/14		12/31/14
Sales
Information
Ansys		343,000		330,000
Commvault Systems		50,000		0
Concur Technologies		54,000		0
Monolithic Power Systems		255,000		152,000
Plexus		215,000		0
RCM Technologies		582,000		302,000
RealPage		275,000		0
SBA Communications		48,000		23,000
Ultratech		238,000		0
Industrial Goods & Services
HEICO		757,500		725,500
Kennametal		264,000		239,000
Moog		368,610		312,000
Nordson		590,000		515,000
PolyOne		73,000		0
Consumer Goods & Services
Avis Budget Group		887,950		791,950
Caesarstone (Israel)		333,814		225,187
Casey's General Stores		204,931		130,279
Fiesta Restaurant Group		112,000		68,000
Interface		688,000		502,000
Pier 1 Imports		243,023		0
Pool		275,000		260,000
Finance
Hudson Valley		89,700		0
MB Financial		801,000		733,000
TCF Financial		487,000		0
Textainer Group Holdings		218,788		83,000
ViewPoint Financial		373,487		0
Heath Care
Akorn		694,200		657,117
Allscripts Healthcare Solutions		724,900		581,600
Cepheid		581,600		558,500
Seattle Genetics		414,000		380,800
Other Industries
Coresite Realty		223,000		0
Hudson Pacific Properties		116,000		0
Kite Realty Group		313,750		0
St. Joe		356,000		153,098

See accompanying notes to financial statements.

Columbia Acorn USA®

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

	Number of Shares
	9/30/14		12/31/14
Sales (continued)
Energy & Minerals
Bill Barrett Corporation		120,000		0
Carrizo Oil & Gas		135,000		120,000
Core Labs (Netherlands)		70,000		55,000
Hornbeck Offshore		224,000		198,000
Laredo Petroleum		159,000		0
Parsley Energy		143,000		0
Rice Energy		45,000		0
Rosetta Resources		237,000		159,000

See accompanying notes to financial statements.

Columbia Acorn USA®

Statement of Investments, December 31, 2014

Number of Shares			Value
			Equities: 99.0%
Information 22.4%
		> Business Software 7.9%
	330,000	Ansys (a)	$	27,060,000
		Simulation Software for Engineers & Designers
	633,000	Informatica (a)		24,139,455
		Enterprise Data Integration Software
	290,000	SPS Commerce (a)		16,422,700
		Supply Chain Management Software Delivered via the Web
	134,000	NetSuite (a)		14,628,780
		End-to-end IT Systems Solution Delivered via the Web
	119,000	DemandWare (a)		6,847,260
		E-Commerce Website Platform for Retailers & Apparel Manufacturers
	82,000	Envestnet (a)		4,029,480
		Technology Platform for Investment Advisors
	128,934	Textura (a)(b)		3,670,751
		Construction Vendor Management Software
	394,187	InContact (a)		3,464,904
		Call Center Systems Delivered via the Web & Telco Services
	96,949	Fleetmatics (a)		3,440,720
		Fleet Management Software
	171,861	Exa (a)		2,024,523
		Simulation Software
	196,000	E2Open (a)(b)		1,883,560
		Supply Chain Management Software & Supplier/Partner Network
	315,000	Five9 (a)(b)		1,411,200
		Call Center Software
	64,563	Workiva (a)		865,144
		Software Platform for Report Creation
	95,950	Covisint (a)		254,267
		Collaboration Software Platform Provider
				110,142,744
		> Instrumentation 6.2%
	157,000	Mettler-Toledo International (a)		47,486,220
		Laboratory Equipment
	427,000	IPG Photonics (a)(b)		31,990,840
		Fiber Lasers
	274,000	Trimble Navigation (a)		7,271,960
		GPS-based Instruments
				86,749,020
		> Computer Services 2.7%
	506,000	ExlService Holdings (a)		14,527,260
		Business Process Outsourcing
	227,000	Virtusa (a)		9,459,090
		Offshore IT Outsourcing
	327,000	WNS - ADR (India) (a)		6,755,820
		Offshore Business Process Outsourcing Services
	465,262	Hackett Group		4,089,653
		IT Integration & Best Practice Research
	302,000	RCM Technologies		2,114,000
		Technology & Engineering Services
				36,945,823

Number of Shares			Value
		> Telecommunications Equipment 1.4%
	710,278	Infinera (a)	$	10,455,292
		Optical Networking Equipment
	281,000	CalAmp (a)		5,142,300
		Machine-to-machine Communications
	369,000	Ixia (a)		4,151,250
		Telecom Network Test Equipment
				19,748,842
		> Semiconductors & Related Equipment 1.1%
	970,000	Atmel (a)		8,143,150
		Microcontrollers, Radio Frequency & Memory Semiconductors
	152,000	Monolithic Power Systems		7,560,480
		High Performance Analog & Mixed Signal Integrated Circuits
	50,657	Rubicon Technology (a)		231,503
		Producer of Sapphire for the Lighting, Electronics & Automotive Industries
				15,935,133
		> Computer Hardware & Related Equipment 1.0%
	101,000	Rogers (a)		8,225,440
		Printed Circuit Materials & High-performance Foams
	78,000	Belden		6,147,180
		Specialty Cable
				14,372,620
		> Financial Processors 0.6%
	95,000	Global Payments		7,669,350
		Credit Card Processor
	153,000	Liquidity Services (a)		1,250,010
		E-Auctions for Surplus & Salvage Goods
				8,919,360
		> Internet Related 0.6%
	280,831	RetailMeNot (a)(b)		4,105,749
		Digital Coupon Marketplace
	951,000	Vonage (a)		3,623,310
		Business & Consumer Internet Telephony
				7,729,059
		> Business Information & Marketing Services 0.4%
	211,000	RPX (a)		2,907,580
		Patent Aggregation & Defensive Patent Consulting
	218,000	Bankrate (a)		2,709,740
		Internet Advertising for the Insurance, Credit Card & Banking Markets
				5,617,320
		> Telephone & Data Services 0.3%
	621,000	Boingo Wireless (a)		4,763,070
		Wholesale & Retail Wi-Fi Networks
		> Mobile Communications 0.2%
	23,000	SBA Communications (a)		2,547,480
		Communications Towers
Information: Total				313,470,471

See accompanying notes to financial statements.

Columbia Acorn USA®

Statement of Investments, continued

Number of Shares			Value
Industrial Goods & Services 22.2%
		> Machinery 17.4%
	793,000	Ametek	$	41,735,590
		Aerospace/Industrial Instruments
	515,000	Nordson		40,149,400
		Dispensing Systems for Adhesives & Coatings
	725,500	HEICO		34,359,680
		FAA-approved Aircraft Replacement Parts
	855,000	Donaldson		33,028,650
		Industrial Air Filtration
	312,000	Moog (a)		23,097,360
		Motion Control Products for Aerospace, Defense & Industrial Markets
	317,000	Generac (a)(b)		14,822,920
		Standby Power Generators
	222,000	Toro		14,165,820
		Turf Maintenance Equipment
	129,000	Middleby (a)		12,783,900
		Manufacturer of Cooking Equipment
	320,000	ESCO Technologies		11,808,000
		Industrial Filtration & Advanced Measurement Equipment
	239,000	Kennametal		8,553,810
		Consumable Cutting Tools
	149,293	Dorman Products (a)(b)		7,206,373
		Aftermarket Auto Parts Distributor
	64,000	Graham		1,841,280
		Designer & Builder of Vacuum & Heat Transfer Equipment for Process Industries
				243,552,783
		> Industrial Materials & Specialty Chemicals 2.0%
	539,000	Drew Industries (a)		27,526,730
		RV & Manufactured Home Components
		> Electrical Components 1.6%
	106,000	Acuity Brands		14,847,420
		Commercial Lighting Fixtures
	312,013	Thermon (a)		7,547,595
		Global Engineered Thermal Solutions
				22,395,015
		> Industrial Distribution 0.5%
	90,000	WESCO International (a)		6,858,900
		Industrial Distributor
		> Other Industrial Services 0.4%
	151,000	KAR Auction Services		5,232,150
		Auto Auctions
		> Construction 0.3%
	449,000	PGT (a)		4,323,870
		Wind Resistant Windows & Doors
Industrial Goods & Services: Total				309,889,448
Consumer Goods & Services 18.2%
		> Travel 5.7%
	791,950	Avis Budget Group (a)		52,530,044
		Car Rental Company
	469,000	Hertz (a)		11,696,860
		U.S. Rental Car Operator

Number of Shares			Value
	281,000	HomeAway (a)	$	8,368,180
		Vacation Rental Online Marketplace
	89,666	Choice Hotels		5,023,089
		Franchisor of Budget Hotel Brands
	29,000	Vail Resorts		2,642,770
		Ski Resort Operator & Developer
				80,260,943
		> Retail 3.6%
	130,279	Casey's General Stores		11,766,799
		Owner/Operator of Convenience Stores
	207,500	Burlington Stores (a)		9,806,450
		Off-price Apparel Retailer
	368,564	Michaels Stores (a)		9,114,588
		Craft & Hobby Specialty Retailer
	185,991	Shutterfly (a)		7,754,895
		Internet Photo-centric Retailer
	184,000	The Fresh Market (a)(b)		7,580,800
		Specialty Food Retailer
	135,000	Kate Spade & Company (a)		4,321,350
		Global Lifestyle Brand
				50,344,882
		> Consumer Goods Distribution 2.4%
	260,000	Pool		16,494,400
		Swimming Pool Supplies & Equipment Distributor
	134,000	United Natural Foods (a)		10,361,550
		Distributor of Natural/Organic Foods to Grocery Stores
	279,000	The Chefs' Warehouse (a)		6,428,160
		Distributor of Specialty Foods to Fine Dining Restaurants
				33,284,110
		> Furniture & Textiles 2.2%
	225,187	Caesarstone (Israel)		13,470,686
		Quartz Countertops
	408,000	Knoll		8,637,360
		Office Furniture
	502,000	Interface		8,267,940
		Modular Carpet
	8,750	Wayfair (a)(b)		173,688
		Online Retailer of Home Furnishings
				30,549,674
		> Other Durable Goods 2.0%
	187,000	Cavco Industries (a)		14,823,490
		Manufactured Homes
	297,000	Select Comfort (a)		8,027,910
		Specialty Mattresses
	148,000	Gentex		5,347,240
		Manufacturer of Auto Parts
				28,198,640
		> Restaurants 0.9%
	79,000	Papa John's International		4,408,200
		Franchisor of Pizza Restaurants
	68,000	Fiesta Restaurant Group (a)		4,134,400
		Owns/Operates Two Restaurant Chains: Pollo Tropical & Taco Cabana
	18,500	Buffalo Wild Wings (a)		3,337,030
		Restaurants
				11,879,630

See accompanying notes to financial statements.

Number of Shares			Value
		> Other Consumer Services 0.7%
	252,000	Blackhawk Network (a)	$	9,497,880
		Third-party Distributer of Prepaid Content, Mostly Gift Cards
		> Food & Beverage 0.6%
	612,705	Boulder Brands (a)		6,776,517
		Healthy Food Products
	65,000	B&G Foods		1,943,500
		Acquirer of Small Food Brands
	15,000	Freshpet (a)(b)		255,900
		Fresh Pet Food Manufacturer & Marketer
				8,975,917
		> Leisure Products 0.1%
	102,184	Fox Factory Holding (a)		1,658,446
		High Performance Suspension Systems for Leisure Market
Consumer Goods & Services: Total				254,650,122
Finance 13.9%
		> Banks 8.9%
	733,000	MB Financial		24,086,380
		Chicago Bank
	993,000	Associated Banc-Corp		18,499,590
		Midwest Bank
	392,597	Lakeland Financial		17,066,192
		Indiana Bank
	140,000	SVB Financial Group (a)		16,249,800
		Bank to Venture Capitalists
	130,000	City National		10,505,300
		Bank & Asset Manager
	1,489,731	First Busey		9,698,149
		Illinois Bank
	228,000	Hancock Holding		6,999,600
		Gulf Coast Bank
	546,750	Valley National Bancorp (b)		5,308,942
		New Jersey/New York Bank
	695,000	TrustCo Bank		5,045,700
		New York State Bank
	171,826	Sandy Spring Bancorp		4,481,222
		Baltimore & Washington, D.C. Bank
	379,000	First Commonwealth		3,494,380
		Western Pennsylvania Bank
	154,849	Guaranty Bancorp		2,236,019
		Colorado Bank
				123,671,274
		> Finance Companies 3.3%
	673,208	CAI International (a)		15,618,426
		International Container Leasing
	180,689	World Acceptance (a)(b)		14,355,741
		Personal Loans
	315,000	McGrath Rentcorp		11,295,900
		Mini Rental Conglomerate
	83,000	Textainer Group Holdings (b)		2,848,560
		Top International Container Leaser
	91,000	Marlin Business Services		1,868,230
		Small Equipment Leasing
				45,986,857

Number of Shares			Value
		> Insurance 0.7%
	33,728	Enstar Group (a)	$	5,156,674
		Insurance/Reinsurance & Related Services
	135,000	Allied World Assurance Company Holdings		5,119,200
		Commercial Lines Insurance/ Reinsurance
				10,275,874
		> Savings & Loans 0.6%
	373,487	ViewPoint Financial		8,907,665
		Texas Thrift
		> Brokerage & Money Management 0.4%
	139,000	SEI Investments		5,565,560
		Mutual Fund Administration & Investment Management
Finance: Total				194,407,230
Health Care 12.6%
		> Biotechnology & Drug Delivery 5.2%
	317,200	Synageva BioPharma (a)(b)		29,432,988
		Biotech Focused on Orphan Diseases
	380,800	Seattle Genetics (a)		12,235,104
		Antibody-based Therapies for Cancer
	349,300	Celldex Therapeutics (a)(b)		6,374,725
		Biotech Developing Drugs for Cancer
	177,200	NPS Pharmaceuticals (a)		6,338,444
		Orphan Drugs & Healthy Royalties
	338,500	Sarepta Therapeutics (a)(b)		4,898,095
		Biotech Focused on Rare Diseases
	46,100	Alnylam Pharmaceuticals (a)		4,471,700
		Biotech Developing Drugs for Rare Diseases
	33,600	BioMarin Pharmaceutical (a)		3,037,440
		Biotech Focused on Orphan Diseases
	17,800	Intercept Pharmaceuticals (a)(b)		2,776,800
		Biotech Developing Drugs for Several Diseases
	60,385	Ultragenyx Pharmaceutical (a)		2,649,694
		Biotech Focused on "Ultra-Orphan" Drugs
				72,214,990
		> Medical Supplies 3.2%
	558,500	Cepheid (a)		30,237,190
		Molecular Diagnostics
	135,200	Bio-Techne		12,492,480
		Cytokines, Antibodies & other Reagents for Life Science
	86,300	VWR (a)(b)		2,232,581
		Distributor of Lab Supplies
				44,962,251
		> Health Care Services 1.9%
	184,500	Medidata Solutions (a)		8,809,875
		Cloud-based Software for Drug Studies
	581,600	Allscripts Healthcare Solutions (a)		7,427,032
		Health Care IT
	124,200	HealthSouth		4,776,732
		Inpatient Rehabilitation Facilities

See accompanying notes to financial statements.

Columbia Acorn USA®

Statement of Investments, continued

Number of Shares			Value
		> Health Care Services—continued
	110,500	Envision Healthcare Holdings (a)	$	3,833,245
		Provider of Health Care Outsourcing Services
	81,900	Castlight Health (a)(b)		958,230
		Provider of Cloud-based Software for Managing Health Care Costs
				25,805,114
		> Pharmaceuticals 1.7%
	657,117	Akorn (a)		23,787,635
		Developer, Manufacturer & Distributor of Specialty Generic Drugs
		> Medical Equipment & Devices 0.6%
	200,300	Wright Medical Group (a)		5,382,061
		Leader in Foot & Ankle Replacement
	61,200	Abaxis		3,477,996
		Instruments & Tests for Vet & Medical Markets
				8,860,057
Health Care: Total				175,630,047
Other Industries 6.8%
		> Real Estate 5.5%
	832,000	Extra Space Storage		48,788,480
		Self Storage Facilities
	328,933	EdR		12,035,659
		Student Housing
	217,750	DCT Industrial Trust		7,764,965
		Industrial Properties
	91,000	Post Properties		5,348,070
		Multifamily Properties
	153,098	St. Joe (a)		2,815,472
		Florida Panhandle Landowner
				76,752,646
		> Transportation 1.3%
	468,091	Rush Enterprises, Class A (a)		15,002,316
	105,000	Rush Enterprises, Class B (a)		2,956,800
		Truck Sales & Service
				17,959,116
Other Industries: Total				94,711,762
Energy & Minerals 2.9%
		> Oil & Gas Producers 1.6%
	120,000	Carrizo Oil & Gas (a)		4,992,000
		Oil & Gas Producer
	77,000	Clayton Williams (a)		4,912,600
		Oil & Gas Producer
	159,000	Rosetta Resources (a)		3,547,290
		Oil & Gas Producer Exploring in Texas
	89,000	SM Energy		3,433,620
		Oil & Gas Producer
	83,000	PDC Energy (a)		3,425,410
		Oil & Gas Producer in the U.S.
	129,000	WPX Energy (a)		1,500,270
		Oil & Gas Produced in the U.S. & Argentina

Number of Shares			Value
	47,000	Bonanza Creek Energy (a)	$	1,128,000
		Oil & Gas Producer in Western U.S.
				22,939,190
		> Oil Services 0.7%
	198,000	Hornbeck Offshore (a)		4,944,060
		Supply Vessel Operator in U.S. Gulf of Mexico
	84,000	Chart Industries (a)		2,872,800
		Manufacturer of Natural Gas Processing/Storage Equipment
	51,000	Gulfport Energy (a)		2,128,740
		Oil & Gas Producer Focused on Utica Shale in Ohio
				9,945,600
		> Mining 0.6%
	55,000	Core Labs (Netherlands) (b)		6,618,700
		Oil & Gas Reservoir Consulting
	49,000	US Silica (b)		1,258,810
		Provider of Frac Sand & Industrial Sand in U.S.
				7,877,510
Energy & Minerals: Total				40,762,300
Total Equities: 99.0% (Cost: $732,454,361)				1,383,521,380	(c)
Short-Term Investments 1.4%
	19,527,766	JPMorgan U.S. Government Money Market Fund, Agency Shares (7 day yield of 0.01%)		19,527,766
Total Short-Term Investments: 1.4% (Cost: $19,527,766)				19,527,766
Securities Lending Collateral 5.6%
	78,364,950	Dreyfus Government Cash Management Fund, Institutional Shares (7 day yield of 0.01%) (d)		78,364,950
Total Securities Lending Collateral: 5.6% (Cost: $78,364,950)				78,364,950
Total Investments: 106.0% (Cost: $830,347,077)(e)				1,481,414,096
Obligation to Return Collateral for Securities Loaned: (5.6)%				(78,364,950	)
Cash and Other Assets Less Liabilities: (0.4)%				(5,832,859	)
Net Assets: 100.0%			$	1,397,216,287

ADR - American Depositary Receipts

See accompanying notes to financial statements.

> Notes to Statement of Investments

(a) Non-income producing security.

(b) All or a portion of this security was on loan at December 31, 2014. The total market value of securities on loan at December 31, 2014 was $76,216,239.

(c) On December 31, 2014, the market value of foreign securities represented 1.92% of total net assets. The Fund's foreign portfolio was diversified as follows:

Country	Value		Percentage of Net Assets
Israel	$	13,470,686		0.97
India		6,755,820		0.48
Netherlands		6,618,700		0.47
Total Foreign Portfolio	$	26,845,206		1.92

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

(e) At December 31, 2014, for federal income tax purposes, the cost of investments was $830,856,619 and net unrealized appreciation was $650,557,477 consisting of gross unrealized appreciation of $693,589,171 and gross unrealized depreciation of $43,031,694.

Fair Value Measurements

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

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

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

Under the direction of the Board, the Committee is responsible for overseeing the valuation procedures approved by the Board.

See accompanying notes to financial statements.

Columbia Acorn USA®

Statement of Investments, continued

> Notes to Statement of Investments

The following table summarizes the inputs used, as of December 31, 2014, 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
Information	$	313,470,471	$	-	$	-	$	313,470,471
Industrial Goods & Services		309,889,448		-		-		309,889,448
Consumer Goods & Services		254,650,122		-		-		254,650,122
Finance		194,407,230		-		-		194,407,230
Health Care		175,630,047		-		-		175,630,047
Other Industries		94,711,762		-		-		94,711,762
Energy & Minerals		40,762,300		-		-		40,762,300
Total Equities		1,383,521,380		-		-		1,383,521,380
Total Short-Term Investments		19,527,766		-		-		19,527,766
Total Securities Lending Collateral		78,364,950		-		-		78,364,950
Total Investments	$	1,481,414,096	$	-	$	-	$	1,481,414,096

The following table shows transfers between Level 1 and Level 3 of the fair value hierarchy:

Transfers In				Transfers Out
Level 1		Level 3		Level 1		Level 3
$	970	$	-	$	-	$	970

Financial assets were transferred from Level 3 to Level 1 as stock resumed trading on an exchange.

See accompanying notes to financial statements.

Columbia Acorn International Select^SM

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	9/30/14		12/31/14
Purchases
Asia
> Japan
KDDI		0		120,000
Recruit Holdings		0		222,500
Secom		88,300		108,000
> Singapore
Singapore Exchange		1,210,000		2,036,000
> Korea
Samsung Fire and Marine		0		23,200
Europe
> United Kingdom
Babcock International		479,000		556,000
> Germany
Telefonica Deutschland		1,293,500		1,305,500
> France
Eutelsat		0		105,081
Other Countries
> Australia
Challenger Financial		2,080,000		2,156,000
> Canada
Goldcorp		256,000		295,000

	Number of Shares
	9/30/14		12/31/14
Sales
Asia
> Japan
Benesse		88,900		0
Dentsu		86,700		0
Japan Tobacco		212,000		190,000
Makita		60,000		0
NGK Spark Plug		285,000		264,000
Park24		218,000		212,000
Rinnai		57,000		38,200
Seven Bank		965,000		777,000
Toyo Suisan Kaisha		60,000		0
> Singapore
Ascendas REIT		9,514,001		7,916,000
Mapletree Logistics Trust		7,600,000		0
> Korea
CJ Corp		57,600		37,000
KT&G		140,000		34,400
> Indonesia
Archipelago Resources		11,903,000		0
Europe
> United Kingdom
Jardine Lloyd Thompson Group		454,285		290,000
Smith and Nephew		200,000		151,000
Whitbread		70,442		47,442
> Sweden
Swedish Match		307,000		248,000
> Switzerland
Swatch		30,000		0
Other Countries
> Australia
IAG		2,486,000		1,300,000
> Canada
Baytex		404,000		370,000
CCL Industries		107,000		78,000
> United States
Denbury Resources		758,000		0

See accompanying notes to financial statements.

Columbia Acorn International Select^SM

Statement of Investments, December 31, 2014

Number of Shares			Value
			Equities: 89.5%
Asia 37.5%
		> Japan 21.8%
	264,000	NGK Spark Plug	$	8,021,752
		Automobile Parts
	120,000	KDDI		7,538,886
		Mobile & Fixed Line Communication Service Provider in Japan
	222,500	Recruit Holdings (a)		6,390,048
		Recruitment & Media Services
	108,000	Secom		6,205,098
		Security Services
	2,560	Nippon Prologis REIT		5,558,413
		Logistics REIT in Japan
	190,000	Japan Tobacco		5,229,329
		Cigarettes
	3,205	Orix JREIT		4,507,153
		Diversified REIT
	777,000	Seven Bank		3,261,448
		ATM Processing Services
	212,000	Park24		3,120,929
		Parking Lot Operator
	1,300	Japan Retail Fund		2,747,269
		Retail REIT in Japan
	38,200	Rinnai		2,566,742
		Gas Appliances for Home & Commercial Use
				55,147,067
		> Singapore 10.3%
	7,916,000	Ascendas REIT		14,199,349
		Industrial Property Landlord
	2,036,000	Singapore Exchange		11,969,879
		Singapore Equity & Derivatives Market Operator
				26,169,228
		> Korea 5.4%
	23,200	Samsung Fire and Marine		5,962,789
		Non-life Insurance
	37,000	CJ Corp		5,238,501
		Holding Company of Korean Consumer Conglomerate
	34,400	KT&G		2,388,508
		Tobacco & Ginseng Products
				13,589,798
Asia: Total				94,906,093
Europe 26.4%
		> United Kingdom 7.7%
	556,000	Babcock International		9,108,546
		Public Sector Outsourcer
	290,000	Jardine Lloyd Thompson Group		4,049,869
		International Business Insurance Broker
	47,442	Whitbread		3,511,004
		UK Hotelier & Coffee Shop
	151,000	Smith and Nephew		2,722,914
		Medical Equipment & Supplies
				19,392,333

Number of Shares			Value
		> Germany 4.6%
	1,305,500	Telefonica Deutschland	$	6,918,953
		Mobile & Fixed-line Communications in Germany
	107,400	Wirecard		4,683,082
		Online Payment Processing & Risk Management
				11,602,035
		> Sweden 4.2%
	248,000	Swedish Match		7,770,961
		Swedish Snus
	97,000	Hexagon		2,992,405
		Design, Measurement & Visualization Software & Equipment
				10,763,366
		> Switzerland 3.1%
	26,680	Partners Group		7,762,207
		Private Markets Asset Management
		> Denmark 2.5%
	67,300	Jyske Bank (a)		3,401,771
		Danish Bank
	71,500	Novozymes		3,009,690
		Industrial Enzymes
				6,411,461
		> Norway 1.6%
	579,000	Orkla		3,941,524
		Food & Brands, Aluminum, Chemicals Conglomerate
		> Spain 1.4%
	66,000	Viscofan		3,501,714
		Sausage Casings Maker
		> France 1.3%
	105,081	Eutelsat		3,398,283
		Fixed Satellite Services
Europe: Total				66,772,923
Other Countries 20.8%
		> Australia 9.2%
	2,156,000	Challenger Financial		11,389,154
		Annuity Provider in Australia
	1,300,000	IAG		6,600,771
		General Insurance Provider
	470,000	Amcor		5,171,098
		Global Leader in Flexible & Rigid Packaging
				23,161,023
		> Canada 7.9%
	78,000	CCL Industries		8,450,559
		Global Label Converter
	370,000	Baytex (b)		6,152,866
		Oil & Gas Producer in Canada
	295,000	Goldcorp		5,463,400
		Gold Mining
				20,066,825

See accompanying notes to financial statements.

Number of Shares			Value
		> South Africa 3.7%
	42,000	Naspers	$	5,432,920
		Media in Africa, China, Russia & other Emerging Markets
	390,000	Coronation Fund Managers		3,859,588
		South African Fund Manager
				9,292,508
Other Countries: Total				52,520,356
Latin America 4.8%
		> Guatemala 3.2%
	588,000	Tahoe Resources		8,173,696
		Silver Project in Guatemala
		> Brazil 0.9%
	12,057,582	Beadell Resources (a)(b)		2,183,800
		Gold Mining in Brazil
		> Uruguay 0.7%
	191,666	Union Agriculture Group (a)(c)(d)		1,749,910
		Farmland Operator in Uruguay
Latin America: Total				12,107,406
Total Equities: 89.5% (Cost: $205,508,509)				226,306,778	(e)

Number of Shares			Value
Short-Term Investments 6.2%
	15,728,035	JPMorgan U.S. Government Money Market Fund, IM Shares (7 day yield of 0.01%)	$	15,728,035
Total Short-Term Investments: 6.2% (Cost: $15,728,035)				15,728,035
Securities Lending Collateral 2.2%
	5,507,307	Dreyfus Government Cash Management Fund, Institutional Shares (7 day yield of 0.01%) (f)		5,507,307
Total Securities Lending Collateral: 2.2% (Cost: $5,507,307)				5,507,307
Total Investments: 97.9% (Cost: $226,743,851)(g)				247,542,120
Obligation to Return Collateral for Securities Loaned: (2.2)%				(5,507,307	)
Cash and Other Assets Less Liabilities: 4.3%				10,884,887
Net Assets: 100.0%			$	252,919,700

REIT - Real Estate Investment Trust

> Notes to Statement of Investments

(a) Non-income producing security.

(b) All or a portion of this security was on loan at December 31, 2014. The total market value of securities on loan at December 31, 2014 was $5,229,212.

(d) Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. This security is valued at fair value determined in good faith under consistently applied procedures established by the Fund's Board of Trustees. At December 31, 2014, the market value of this security amounted to $1,749,910, which represented 0.69% of total net assets. Additional information on this security is as follows:

Security				Acquisition Dates				Shares/Units				Cost				Value
Union Agriculture Group				12/8/10-6/27/12					191,666			$	2,200,000			$	1,749,910

(e) On December 31, 2014, the Fund's total equity investments were denominated in currencies as follows:

Currency	Value		Percentage of Net Assets
Japanese Yen	$	55,147,067		21.8
Singapore Dollar		26,169,228		10.3
Australian Dollar		25,344,822		10.0
Canadian Dollar		22,777,122		9.0
British Pound		19,392,333		7.7
Euro		18,502,032		7.3
South Korean Won		13,589,798		5.4
Other currencies less than 5% of total net assets		45,384,376		18.0
Total Equities	$	226,306,778		89.5

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

See accompanying notes to financial statements.

Columbia Acorn International Select^SM

Statement of Investments, continued

> Notes to Statement of Investments

(g) At December 31, 2014, for federal income tax purposes, the cost of investments was $234,189,129 and net unrealized appreciation was $13,352,991 consisting of gross unrealized appreciation of $39,595,587 and gross unrealized depreciation of $26,242,596.

At December 31, 2014, the Fund had entered into the following forward foreign currency exchange contracts:

Forward Foreign Currency Exchange Contracts to Buy				Forward Foreign Currency Exchange Contracts to Sell				Principal Amount in Foreign Currency				Principal Amount in U.S. Dollar				Settlement Date				Unrealized Appreciation (Depreciation)
USD				ZAR					105,407,100			$	9,000,000			1/15/15				$	(97,181	)

The counterparty for all forward foreign currency exchange contracts is Morgan Stanley.

USD - United States Dollar

ZAR - South African Rand

Fair Value Measurements

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

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

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

Under the direction of the Board, the Committee is responsible for overseeing the valuation procedures approved by the Board.

For investments and derivatives categorized as Level 3, the significant unobservable inputs used in the fair value measurement of the Funds' securities may include: (i) data specific to the issuer or comparable issuers, (ii) general market or specific sector news and (iii) quoted prices and specific or similar security transactions. The Committee considers this data and any changes from prior periods in order to assess the reasonableness of observable and unobservable inputs, any assumptions or internal models used to value those securities and changes in fair value. Significant changes in any of these factors could result in lower or higher fair value measurements. Various factors impact the frequency of monitoring (which may occur as often as daily), however the Committee may determine that changes to inputs, assumptions and models are not required with the same frequency.

See accompanying notes to financial statements.

> Notes to Statement of Investments

The following table summarizes the inputs used, as of December 31, 2014, 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
Asia	$	-	$	94,906,093		$	-	$	94,906,093
Europe		-		66,772,923			-		66,772,923
Other Countries		20,066,825		32,453,531			-		52,520,356
Latin America		8,173,696		2,183,800			1,749,910		12,107,406
Total Equities		28,240,521		196,316,347			1,749,910		226,306,778
Total Short-Term Investments		15,728,035		-			-		15,728,035
Total Securities Lending Collateral		5,507,307		-			-		5,507,307
Total Investments	$	49,475,863	$	196,316,347		$	1,749,910	$	247,542,120
Unrealized Depreciation on:
Forward Foreign Currency Exchange Contracts		-		(97,181	)		-		(97,181	)
Total	$	49,475,863	$	196,219,166		$	1,749,910	$	247,444,939

The Fund's assets assigned to the Level 2 input category are generally valued using a market approach, in which a security's value is determined through its correlation to prices and information from observable market transactions for similar or identical assets. Foreign equities are generally valued at the last sale price on the foreign exchange or market on which they trade. The Fund may use a statistical fair valuation model, in accordance with the policy adopted by the Board, provided by an independent third party to value securities principally traded in foreign markets in order to adjust for possible stale pricing that may occur between the close of the foreign exchanges and the time for valuation. These models take into account available market data including intraday index, ADR, and ETF movements. Forward foreign currency exchange contracts are valued at the prevailing forward exchange rate of the underlying currencies.

There were no transfers of financial assets between levels during the period.

The following table reconciles asset balances for the period ending December 31, 2014, in which significant observable and/or unobservable inputs (Level 3) were used in determining value:

Investments in Securities	Balance as of December 31, 2013		Realized Gain/(Loss)			Change in Unrealized Appreciation (Depreciation)			Purchases		Sales			Transfers into Level 3		Transfers out of Level 3		Balance as of December 31, 2014
Equities
Asia	$	10,249,601	$	(1,522,004	)	$	1,817,376		$	-	$	(10,544,973	)	$	-	$	-	$	-
Latin America		2,048,910		-			(299,000	)		-		-			-		-		1,749,910
Options
Asia		985,539		-			(985,539	)		-		-			-		-		-
	$	13,284,050	$	(1,522,004	)	$	532,837		$	-	$	(10,544,973	)	$	-	$	-	$	1,749.910

The information in the above reconciliation table 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.

The change in unrealized depreciation attributed to securities owned at December 31, 2014, which were valued using significant unobservable inputs (Level 3), amounted to $299,000.

Quantitative information pertaining to Level 3 unobservable fair value measurements

Fair Value at
12/31/14

Valuation Technique(s)

Unobservable Input(s)

Range (Weighted
Average)

Equities

Latin America

1,749,910

Market comparable companies

Discount for lack of marketability

% to 23%

See accompanying notes to financial statements.

Columbia Acorn International Select^SM

Portfolio Diversification

At December 31, 2014, the Fund's portfolio investments as a percentage of net assets were diversified as follows:

	Value		Percentage of Net Assets
> Information
Financial Processors	$	16,652,961		6.6
Mobile Communications		7,538,886		3.0
Telephone & Data Services		6,918,953		2.7
Advertising		6,390,048		2.5
Internet Related		5,432,920		2.1
Satellite Broadcasting & Services		3,398,283		1.4
Business Software		2,992,405		1.2
		49,324,456		19.5
> Finance
Insurance		28,002,584		11.1
Brokerage & Money Management		11,621,795		4.6
Banks		6,663,219		2.6
		46,287,598		18.3
> Consumer Goods & Services
Nondurables		16,068,397		6.3
Food & Beverage		11,272,675		4.5
Other Durable Goods		10,588,494		4.2
Restaurants		3,511,004		1.4
		41,440,570		16.4
> Industrial Goods & Services
Other Industrial Services		9,326,027		3.7
Conglomerates		9,180,024		3.6
Outsourcing Services		9,108,546		3.6
Industrial Materials & Specialty Chemicals		8,180,787		3.2
		35,795,384		14.1
> Other Industries
Real Estate		27,012,184		10.7
		27,012,184		10.7
> Energy & Minerals
Mining		15,820,895		6.3
Oil & Gas Producers		6,152,866		2.4
Agricultural Commodities		1,749,911		0.7
		23,723,672		9.4

	Value			Percentage of Net Assets
> Health Care
Medical Equipment & Devices	$	2,722,914			1.1
		2,722,914			1.1
Total Equities:		226,306,778			89.5
Short-Term Investments:		15,728,035			6.2
Securities Lending Collateral:		5,507,307			2.2
Total Investments:		247,542,120			97.9
Obligation to Return Collateral for Securities Loaned:		(5,507,307	)		(2.2	)
Cash and Other Assets Less Liabilities:		10,884,887			4.3
Net Assets:	$	252,919,700			100.0

See accompanying notes to financial statements.

Columbia Acorn Select^SM

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	9/30/14		12/31/14
Purchases
Health Care
Intercept Pharmaceuticals		0		18,000
VWR		0		325,000
Energy & Minerals
Core Labs (Netherlands)		0		27,000
Petromanas (Canada)		15,399,500		16,000,000

	Number of Shares
	9/30/14		12/31/14
Sales
Industrial Goods & Services
Ametek		865,000		779,000
Donaldson		800,000		764,000
Kennametal		355,000		280,000
Nordson		300,000		272,000
Quanta Services		570,000		525,000
Information
SBA Communications		114,300		83,000
WNS - ADR (India)		1,395,000		1,245,493
Finance
CNO Financial Group		1,830,000		1,270,000
Discover Financial Services		390,000		319,000
SEI Investments		645,000		610,000
Consumer Goods & Services
Choice Hotels		100,000		0
Hertz		380,000		138,000
Heath Care
Henry Schein		110,000		41,000
Other Industries
Post Properties		367,000		355,000
Energy & Minerals
Antero Resources		58,300		0
Canacol (Colombia)		1,880,000		1,654,000
Clayton Williams		28,000		0
ShaMaran Petroleum (Iraq)		20,600,000		20,290,500
Synthesis Energy Systems (China)		2,000,000		882,000

See accompanying notes to financial statements.

Columbia Acorn Select^SM

Statement of Investments, December 31, 2014

Number of Shares			Value
			Equities: 99.1%
Industrial Goods & Services 26.5%
		> Machinery 18.0%
	779,000	Ametek	$	40,998,770
		Aerospace/Industrial Instruments
	764,000	Donaldson		29,513,320
		Industrial Air Filtration
	272,000	Nordson		21,205,120
		Dispensing Systems for Adhesives & Coatings
	177,000	Pall		17,914,170
		Life Science, Water & Industrial Filtration
	280,000	Kennametal		10,021,200
		Consumable Cutting Tools
				119,652,580
		> Other Industrial Services 3.3%
	780,000	LKQ (a)		21,933,600
		Alternative Auto Parts Distribution
		> Industrial Distribution 3.0%
	175,000	Airgas		20,156,500
		Industrial Gas Distributor
		> Outsourcing Services 2.2%
	525,000	Quanta Services (a)		14,904,750
		Electrical Transmission & Pipeline Contracting Services
Industrial Goods & Services: Total				176,647,430
Information 24.5%
		> Instrumentation 5.9%
	84,500	Mettler-Toledo International (a)		25,557,870
		Laboratory Equipment
	525,000	Trimble Navigation (a)		13,933,500
		GPS-based Instruments
				39,491,370
		> Computer Hardware & Related Equipment 4.3%
	534,000	Amphenol		28,734,540
		Electronic Connectors
		> Computer Services 3.9%
	1,245,493	WNS - ADR (India) (a)		25,731,885
		Offshore Business Process Outsourcing Services
		> Business Software 3.7%
	190,000	Ansys (a)		15,580,000
		Simulation Software for Engineers & Designers
	241,000	Informatica (a)		9,190,535
		Enterprise Data Integration Software
				24,770,535
		> Telecommunications Equipment 3.7%
	187,000	F5 Networks (a)		24,396,955
		Internet Traffic Management Equipment

Number of Shares			Value
		> Mobile Communications 1.4%
	83,000	SBA Communications (a)	$	9,193,080
		Communications Towers
		> Internet Related 0.9%
	1,635,000	Vonage (a)		6,229,350
		Business & Consumer Internet Telephony
		> Semiconductors & Related Equipment 0.7%
	535,000	Atmel (a)		4,491,325
		Microcontrollers, Radio Frequency & Memory Semiconductors
Information: Total				163,039,040
Finance 14.3%
		> Banks 4.2%
	200,000	City National		16,162,000
		Bank & Asset Manager
	635,000	Associated Banc-Corp		11,830,050
		Midwest Bank
				27,992,050
		> Brokerage & Money Management 3.7%
	610,000	SEI Investments		24,424,400
		Mutual Fund Administration & Investment Management
		> Insurance 3.3%
	1,270,000	CNO Financial Group		21,869,400
		Life, Long-term Care & Medical Supplement Insurance
		> Credit Cards 3.1%
	319,000	Discover Financial Services		20,891,310
		Credit Card Company
Finance: Total				95,177,160
Consumer Goods & Services 14.2%
		> Retail 6.0%
	440,000	The Fresh Market (a)(b)		18,128,000
		Specialty Food Retailer
	109,000	ULTA (a)		13,934,560
		Specialty Beauty Product Retailer
	86,875	Casey's General Stores		7,846,550
		Owner/Operator of Convenience Stores
				39,909,110
		> Travel 3.4%
	210,000	Vail Resorts		19,137,300
		Ski Resort Operator & Developer
	138,000	Hertz (a)		3,441,720
		U.S. Rental Car Operator
				22,579,020
		> Other Consumer Services 1.6%
	294,000	Blackhawk Network (a)		11,080,860
		Third-party Distributer of Prepaid Content, Mostly Gift Cards
		> Apparel 1.6%
	83,000	PVH		10,638,110
		Apparel Wholesaler & Retailer

See accompanying notes to financial statements.

Number of Shares			Value
		> Consumer Goods Distribution 1.5%
	134,000	United Natural Foods (a)	$	10,361,550
		Distributor of Natural/Organic Foods to Grocery Stores
		> Food & Beverage 0.1%
	1,500,000	GLG Life Tech (Canada) (a)		413,152
		Producer of an All-natural Sweetener Extracted from the Stevia Plant
Consumer Goods & Services: Total				94,981,802
Health Care 7.7%
		> Medical Supplies 4.7%
	322,500	Cepheid (a)		17,460,150
		Molecular Diagnostics
	325,000	VWR (a)(b)		8,407,750
		Distributor of Lab Supplies
	41,000	Henry Schein (a)		5,582,150
		Large Distributor of Dental, Vet & Medical Products
				31,450,050
		> Biotechnology & Drug Delivery 3.0%
	131,000	Synageva BioPharma (a)(b)		12,155,490
		Biotech Focused on Orphan Diseases
	148,000	Seattle Genetics (a)		4,755,240
		Antibody-based Therapies for Cancer
	18,000	Intercept Pharmaceuticals (a)(b)		2,808,000
		Biotech Developing Drugs for Several Diseases
				19,718,730
Health Care: Total				51,168,780
Other Industries 7.0%
		> Real Estate 7.0%
	355,000	Post Properties		20,863,350
		Multifamily Properties
	230,000	Extra Space Storage		13,487,200
		Self Storage Facilities
	341,666	EdR		12,501,559
		Student Housing
				46,852,109
Other Industries: Total				46,852,109
Energy & Minerals 4.9%
		> Agricultural Commodities 2.4%
	1,742,424	Union Agriculture Group (Uruguay) (a)(c)(d)		15,908,331
		Farmland Operator in Uruguay
		> Oil & Gas Producers 1.3%
	1,654,000	Canacol (Colombia) (a)		3,530,659
		Oil Producer in South America
	20,290,500	ShaMaran Petroleum (Iraq) (a)		1,921,118
		Oil Exploration & Production in Kurdistan

Number of Shares			Value
	22,500,000	Canadian Overseas Petroleum (Canada) (a)(c)(e)	$	1,839,818
		Oil & Gas Exploration Offshore West Africa
	16,000,000	Petromanas (Canada) (a)(b)		826,304
		Exploring for Oil in Albania
	3,370,000	Petrodorado Energy (Colombia) (a)(e)		391,591
		Oil & Gas Exploration & Production in Colombia, Peru & Paraguay
				8,509,490
		> Oil Services 0.6%
	173,000	Rowan		4,034,360
		Contract Offshore Driller
		> Mining 0.5%
	27,000	Core Labs (Netherlands) (b)		3,249,180
		Oil & Gas Reservoir Consulting
		> Alternative Energy 0.1%
	882,000	Synthesis Energy Systems (China) (a)(b)		835,254
		Owner/Operator of Gasification Plants/Technology Licenses
Energy & Minerals: Total				32,536,615
Total Equities: 99.1% (Cost: $453,984,082)				660,402,936	(f)
Short-Term Investments 1.3%
	8,870,699	JPMorgan U.S. Government Money Market Fund, Agency Shares (7 day yield of 0.01%)		8,870,699
Total Short-Term Investments: 1.3% (Cost: $8,870,699)				8,870,699
Securities Lending Collateral 3.8%
	25,598,975	Dreyfus Government Cash Management Fund, Institutional Shares (7 day yield of 0.01%) (g)		25,598,975
Total Securities Lending Collateral: 3.8% (Cost: $25,598,975)				25,598,975
Total Investments: 104.2% (Cost: $488,453,756)(h)				694,872,610
Obligation to Return Collateral for Securities Loaned: (3.8)%				(25,598,975	)
Cash and Other Assets Less Liabilities: (0.4)%				(2,696,849	)
Net Assets: 100.0%			$	666,576,786

ADR - American Depositary Receipts

See accompanying notes to financial statements.

Columbia Acorn Select^SM

Statement of Investments, continued

> Notes to Statement of Investments

(a) Non-income producing security.

(b) All or a portion of this security was on loan at December 31, 2014. The total market value of securities on loan at December 31, 2014 was $25,021,001.

(c) Denotes a restricted security, which is subject to restrictions on resale under federal securities laws. These securities are valued at fair value determined in good faith under consistently applied procedures established by the Fund's Board of Trustees. At December 31, 2014, the market value of these securities amounted to $17,748,149, which represented 2.66% of total net assets. Additional information on these securities is as follows:

Security	Acquisition Dates	Shares/Units		Cost		Value
Union Agriculture Group	12/8/10-6/27/12		1,742,424	$	20,000,000	$	15,908,331
Canadian Overseas Petroleum	11/24/10		22,500,000		9,596,330		1,839,818
				$	29,596,330	$	17,748,149

(d) Illiquid security.

(e) An affiliated person of the Fund, as defined in the Investment Company Act of 1940, may include any company in which the Fund owns five percent or more of its outstanding voting shares. Holdings and transactions in these affiliated companies during the year ended December 31, 2014, are as follows:

Security	Balance of Shares Held 12/31/13		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/14		Value		Dividend
Canadian Overseas Petroleum		24,000,000		-		1,500,000		22,500,000	$	1,839,818	$	-
Petrodorado Energy (1)		3,370,000		-		-		3,370,000		391,591		-
IFM Investments (Century 21 China RE) - ADR (2)		898,852		-		898,852		-		-		-
Total of Affiliated Transactions		28,268,852		-		2,398,852		25,870,000	$	2,231,409	$	-

(1) Includes the effects of a stock split.

(2) At December 31, 2014, the Fund owned less than five percent of the company's outstanding voting shares.

The aggregate cost and value of these companies at December 31, 2014, was $23,207,419 and $2,231,409, respectively. Investments in affiliated companies represented 0.33% of the Fund's total net assets at December 31, 2014.

(f) On December 31, 2014, the market value of foreign securities represented 8.20% of total net assets. The Fund's foreign portfolio was diversified as follows:

Country	Value		Percentage of Net Assets
India	$	25,731,885		3.86
Uruguay		15,908,331		2.39
Colombia		3,922,250		0.59
Netherlands		3,249,180		0.49
Canada		3,079,274		0.46
Iraq		1,921,118		0.29
China		835,254		0.12
Total Foreign Portfolio	$	54,647,292		8.20

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

(h) At December 31, 2014, for federal income tax purposes, the cost of investments was $488,469,458 and net unrealized appreciation was $206,403,152 consisting of gross unrealized appreciation of $258,900,776 and gross unrealized depreciation of $52,497,624.

Fair Value Measurements

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

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

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

See accompanying notes to financial statements.

> Notes to Statement of Investments

Level 2 securities include exchange traded foreign equities that are statistically fair valued, forward foreign currency exchange contracts and short-term investments valued at amortized cost. Additionally, securities fair valued by the Valuation Committee (the Committee) of the Fund's Board of Trustees (the Board) that rely on significant observable inputs are also included in Level 2. Typical Level 3 securities include any security fair valued by the Committee that relies on significant unobservable inputs.

Under the direction of the Board, the Committee is responsible for overseeing the valuation procedures approved by the Board.

The following table summarizes the inputs used, as of December 31, 2014, 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
Industrial Goods & Services	$	176,647,430	$	-	$	-	$	176,647,430
Information		163,039,040		-		-		163,039,040
Finance		95,177,160		-		-		95,177,160
Consumer Goods & Services		94,981,802		-		-		94,981,802
Health Care		51,168,780		-		-		51,168,780
Other Industries		46,852,109		-		-		46,852,109
Energy & Minerals		14,788,466		1,839,818		15,908,331		32,536,615
Total Equities		642,654,787		1,839,818		15,908,331		660,402,936
Total Short-Term Investments		8,870,699		-		-		8,870,699
Total Securities Lending Collateral		25,598,975		-		-		25,598,975
Total Investments	$	677,124,461	$	1,839,818	$	15,908,331	$	694,872,610

There were no transfers of financial assets between levels during the period.

See accompanying notes to financial statements.

Columbia Acorn Select^SM

Statement of Investments, continued

> Notes to Statement of Investments

The following table reconciles asset balances for the period ending December 31, 2014, in which significant observable and/or unobservable inputs (Level 3) were used in determining value:

Investments in Securities	Balance as of December 31, 2013		Realized Gain/(Loss)		Change in Unrealized Appreciation (Depreciation)			Purchases		Sales		Transfers into Level 3		Transfers out of Level 3		Balance as of December 31, 2014
Equities
Energy & Minerals	$	18,626,513	$	-	$	(2,718,182	)	$	-	$	-	$	-	$	-	$	15,908,331

The change in unrealized depreciation attributed to securities owned at December 31, 2014, which were valued using significant unobservable inputs (Level 3), amounted to $2,718,182.

Quantitative information pertaining to Level 3 unobservable fair value measurements

Fair Value at
12/31/14

Valuation Technique(s)

Unobservable Input(s)

Range (Weighted
Average)

Equities

Energy & Minerals

15,908,331

Market comparable companies

Discount for lack of marketability

% to 23%

See accompanying notes to financial statements.

Columbia Thermostat Fund^SM

Statement of Investments, December 31, 2014

Number of Shares			Value
		> Affiliated Bond Funds 84.7%
	42,849,246	Columbia Short Term Bond Fund, Class I (a)	$	425,493,009
	28,994,280	Columbia Intermediate Bond Fund, Class I (a)		266,747,380
	21,780,174	Columbia Income Opportunities Fund, Class I (a)		215,841,525
	28,883,507	Columbia U.S. Government Mortgage Fund, Class I (a)		159,436,960
Total Affiliated Bond Funds: (Cost: $1,062,552,282)				1,067,518,874
		> Affiliated Stock Funds 14.8%
	898,450	Columbia Acorn International, Class I (a)		37,519,294
	1,962,468	Columbia Dividend Income Fund, Class I (a)		37,228,026
	879,308	Columbia Acorn Fund, Class I (a)(b)		28,164,234
	1,291,662	Columbia Contrarian Core Fund, Class I (a)		27,938,640
	836,113	Columbia Acorn Select, Class I (a)(b)		18,712,209
	870,296	Columbia Large Cap Enhanced Core Fund, Class I (a)		18,554,702
	1,023,561	Columbia Select Large Cap Growth Fund, Class I (a)(b)		18,403,623
Total Affiliated Stock Funds: (Cost: $155,181,763)				186,520,728

Number of Shares			Value
		> Short-Term Investments 0.5%
	5,937,697	JPMorgan U.S. Government Money Market Fund, Agency Shares (7 day yield of 0.01%)	$	5,937,697
Total Short-Term Investments: (Cost: $5,937,697)				5,937,697
Total Investments: 100.0% (Cost: $1,223,671,742)(c)				1,259,977,299
Cash and Other Assets Less Liabilities: —%				435,762
Net Assets: 100.0%			$	1,260,413,061

> Notes to Statement of Investments

Security	Balance of Shares Held 12/31/13		Purchases/ Additions		Sales/ Reductions		Balance of Shares Held 12/31/14		Value		Dividend
Columbia Short Term Bond Fund, Class I		47,811,438		21,001,259		25,963,451		42,849,246	$	425,493,009	$	5,476,282
Columbia Intermediate Bond Fund, Class I		39,903,530		15,023,663		25,932,913		28,994,280		266,747,380		8,059,718
Columbia Income Opportunities Fund, Class I		35,741,824		10,185,702		24,147,352		21,780,174		215,841,525		12,782,472
Columbia U.S. Government Mortgage Fund, Class I		-		40,544,101		11,660,594		28,883,507		159,436,960		2,938,266
Columbia Acorn International, Class I		583,352		2,407,588		2,092,490		898,450		37,519,294		410,826
Columbia Dividend Income Fund, Class I		1,469,969		5,839,015		5,346,516		1,962,468		37,228,026		837,639
Columbia Acorn Fund, Class I		545,386		2,488,426		2,154,504		879,308		28,164,234		-
Columbia Contrarian Core Fund, Class I		984,664		3,880,700		3,573,702		1,291,662		27,938,640		159,958
Columbia Acorn Select, Class I		509,430		2,321,133		1,994,450		836,113		18,712,209		-
Columbia Large Cap Enhanced Core Fund, Class I		720,935		2,745,450		2,596,089		870,296		18,554,702		183,662
Columbia Select Large Cap Growth Fund, Class I		700,545		3,134,121		2,811,105		1,023,561		18,403,623		-
Total of Affiliated Transactions		128,971,073		109,571,158		108,273,166		130,269,065	$	1,254,039,602	$	30,848,823

The aggregate cost and value of these companies at December 31, 2014, was $1,217,734,045 and $1,254,039,602, respectively. Investments in affiliated companies represented 99.49% of the Fund's total net assets at December 31, 2014.

See accompanying notes to financial statements.

Columbia Thermostat Fund^SM

Statement of Investments, continued

> Notes to Statement of Investments

(b) Non-income producing security.

(c) At December 31, 2014, for federal income tax purposes, the cost of investments was $1,227,297,910 and net unrealized appreciation was $32,679,389 consisting of gross unrealized appreciation of $34,614,963 and gross unrealized depreciation of $1,935,574.

Fair Value Measurements

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

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

The inputs or methodology 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 Fund would typically invest and how they are classified within this hierarchy are as follows. Typical Level 1 securities include mutual funds whose NAVs are published each day.

Under the direction of the Board, the Committee is responsible for overseeing the valuation procedures approved by the Board.

The following table summarizes the inputs used, as of December 31, 2014, in valuing the Fund's assets:

Investment Type	Quoted Prices (Level 1)		Other Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Total Affiliated Bond Funds	$	1,067,518,874	$	-	$	-	$	1,067,518,874
Total Affiliated Stock Funds		186,520,728		-		-		186,520,728
Total Short-Term Investments		5,937,697		-		-		5,937,697
Total Investments	$	1,259,977,299	$	-	$	-	$	1,259,977,299

There were no transfers of financial assets between levels during the period.

See accompanying notes to financial statements.

Columbia Acorn Emerging Markets Fund^SM

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	9/30/14		12/31/14
Purchases
Asia
> Taiwan
Ginko International		324,500		360,000
President Chain Store		742,000		1,058,000
St. Shine Optical		377,000		420,000
Vanguard International Semiconductor		951,000		3,461,000
> China
AMVIG Holdings		13,822,000		30,774,000
Phoenix New Media - ADR		0		257,000
> Indonesia
Link Net		0		11,800,000
> Philippines
Puregold Price Club		7,193,200		8,198,200
> Korea
The Basic House		0		358,365
Europe
> United Kingdom
Cable and Wireless		9,054,086		10,175,965
PureCircle		22,341		544,900
> Spain
Prosegur		840,828		1,148,390
> Italy
Pirelli		324,156		393,882
> Turkey
Aviva		0		54,624
Latin America
> Brazil
Odontoprev		1,275,100		1,430,100
> Mexico
Genomma Lab International		2,180,100		2,278,100
> Chile
Forus		1,258,078		1,943,078
> Colombia
Isagen		5,842,782		6,047,782

	Number of Shares
	9/30/14		12/31/14
Sales
Asia
> Taiwan
Advantech		724,988		720,988
Chroma Ate		2,086,990		2,050,990
Delta Electronics		833,000		0
Far EasTone Telecom		1,738,000		0
Lite-On Technology		3,087,291		0
PChome Online		765,302		570,000
> China
Biostime		830,000		0
Jumei International - ADR		212,636		0
Sihuan Pharmaceuticals		13,900,000		11,951,000
WuXi PharmaTech - ADR		313,642		307,909
> Indonesia
Archipelago Resources		1,591,929		0
Matahari Department Store		7,426,700		6,909,600
MNC Skyvision		62,000,000		61,966,600
Surya Citra Media		17,095,479		0
Tower Bersama Infrastructure		9,010,709		6,744,300
> India
Adani Ports & Special Economic Zone		1,808,593		1,737,269
Bosch		37,774		17,632
Colgate Palmolive India		222,910		190,350
United Breweries		445,596		419,349
> Philippines
Melco Crown (Philippines) Resorts		55,239,300		39,172,300
Robinsons Retail Holdings		4,498,580		3,814,910
Security Bank		1,882,390		1,601,770
> Korea
Koh Young Technology		373,088		295,533
> Hong Kong
Sa Sa International		15,134,799		7,471,799
Vitasoy International		3,920,000		3,698,000
> Thailand
Samui Airport Property Fund		10,340,200		10,016,800
> Singapore
Super Group		1,079,000		0
> Japan
Kansai Paint		447,760		310,760

See accompanying notes to financial statements.

Columbia Acorn Emerging Markets Fund^SM

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

	Number of Shares
	9/30/14		12/31/14
Sales (continued)
Europe
> Sweden
Hexagon		347,064		288,064
> France
Eutelsat		163,000		161,154
> Finland
Vacon		265,727		0
Latin America
> Brazil
Beadell Resources		11,145,526		3,663,018
Localiza Rent A Car		718,970		557,970
> Mexico
Gruma		652,200		0
Grupo Aeroportuario del Sureste - ADR		42,927		40,525
Other Countries
> South Africa
Coronation Fund Managers		2,048,460		2,003,746
Massmart Holdings		463,782		0
Mr. Price		399,378		288,041
Rand Merchant Insurance		4,343,702		2,851,148
> United States
Bladex		196,000		171,094
Textainer Group Holdings		153,472		0
> Morocco
Holcim Maroc		9,302		4,273
Lafarge Maroc		3,000		0
> Canada
CAE		507,892		0

See accompanying notes to financial statements.

Columbia Acorn Emerging Markets Fund^SM

Statement of Investments, December 31, 2014

Number of Shares			Value
			Equities: 92.6%
Asia 61.7%
		> Taiwan 9.6%
	1,058,000	President Chain Store	$	8,171,806
		Taiwanese Convenience Chain Store Operator
	420,000	St. Shine Optical		6,852,154
		Disposable Contact Lens Original Equipment Manufacturer
	570,000	PChome Online		6,119,510
		Taiwanese Internet Retail Company
	3,461,000	Vanguard International Semiconductor		5,663,384
		Semiconductor Foundry
	71,000	Largan Precision		5,314,795
		Mobile Device Camera Lenses & Modules
	2,050,990	Chroma Ate		5,304,128
		Automatic Test Systems, Testing & Measurement Instruments
	720,988	Advantech		5,293,043
		Industrial PC & Components
	360,000	Ginko International		3,799,009
		Contact Lens Maker in China
				46,517,829
		> China 9.6%
	30,774,000	AMVIG Holdings		13,294,333
		Chinese Tobacco Packaging Material Supplier
	307,909	WuXi PharmaTech - ADR (a)		10,367,296
		Contract Research Organization Business in China
	114,558	BitAuto - ADR (a)		8,066,029
		Automotive Information Website for Buyers & Dealers
	11,951,000	Sihuan Pharmaceuticals		7,949,312
		Chinese Generic Drug Manufacturer
	11,330,000	NewOcean Energy		4,350,120
		Southern China Liquefied Petroleum Gas Distributor
	257,000	Phoenix New Media - ADR (a)		2,135,670
		Internet Advertising
				46,162,760
		> Indonesia 8.3%
	6,909,600	Matahari Department Store		8,325,798
		Department Store Chain in Indonesia
	61,966,600	MNC Skyvision		8,005,374
		Satellite Pay TV Operator in Indonesia
	6,744,300	Tower Bersama Infrastructure		5,274,829
		Communications Towers
	82,889,190	Ace Indonesia		5,240,181
		Home Improvement Retailer
	11,800,000	Link Net (a)		4,687,606
		Fixed Broadband & CATV Service Provider
	66,827,700	Arwana Citramulia		4,672,260
		Ceramic Tiles for Home Decoration
	2,183,600	Mayora Indah		3,684,147
		Consumer Branded Food Manufacturer
				39,890,195

Number of Shares			Value
		> India 8.2%
	2,422,982	Zee Entertainment Enterprises	$	14,554,601
		Programmer of Pay Television Content
	1,737,269	Adani Ports & Special Economic Zone		8,744,542
		Indian West Coast Shipping Port
	419,349	United Breweries		5,528,264
		Brewer
	17,632	Bosch		5,445,253
		Automotive Parts
	190,350	Colgate Palmolive India		5,375,990
		Consumer Products in Oral Care
				39,648,650
		> Philippines 7.7%
	39,172,300	Melco Crown (Philippines) Resorts (a)(b)		11,847,879
		Integrated Resort Operator in Manila
	8,198,200	Puregold Price Club		7,022,694
		Supermarket Operator in the Philippines
	3,814,910	Robinsons Retail Holdings		6,455,903
		Multi-format Retailer in the Philippines
	56,400,000	RFM Corporation		6,312,286
		Flour, Bread, Pasta & Ice Cream Manufacturer/Distributor in the Philippines
	1,601,770	Security Bank		5,425,569
		Commercial Bank in the Philippines
				37,064,331
		> Korea 4.7%
	295,533	Koh Young Technology		11,460,489
		Inspection Systems for Printed Circuit Boards
	358,365	The Basic House		4,749,783
		Casual & Formal Apparel in China
	132,149	Grand Korea Leisure		3,840,763
		'Foreigner Only' Casino Group in Korea
	121,818	Paradise		2,596,692
		Korean Casino Operator
				22,647,727
		> Hong Kong 4.5%
	5,181,000	Melco International		11,341,826
		Macau Casino Operator
	3,698,000	Vitasoy International		5,347,922
		Hong Kong Soy Food Brand
	7,471,799	Sa Sa International (b)		5,212,405
		Cosmetics Retailer
				21,902,153
		> Thailand 3.2%
	21,126,235	Home Product Center		5,287,194
		Home Improvement Retailer
	10,016,800	Samui Airport Property Fund		5,267,193
		Thai Airport Operator
	3,737,700	Robinson Department Store		5,087,575
		Department Store Operator in Thailand
				15,641,962

See accompanying notes to financial statements.

Columbia Acorn Emerging Markets Fund^SM

Statement of Investments, continued

Number of Shares			Value
		> Cambodia 2.0%
	11,570,000	Nagacorp	$	9,428,460
		Casino & Entertainment Complex in Cambodia
		> Malaysia 1.8%
	10,810,900	7-Eleven Malaysia Holdings (a)		4,637,881
		Exclusive 7-Eleven Franchisor for Malaysia
	4,592,100	Aeon		4,124,459
		Shopping Center & Department Store Operator
				8,762,340
		> Singapore 1.1%
	1,829,000	Petra Foods		5,241,804
		Chocolate Manufacturer in South East Asia
		> Japan 1.0%
	310,760	Kansai Paint		4,814,286
		Paint Producer in Japan, India, China & Southeast Asia
Asia: Total				297,722,497
Europe 11.4%
		> United Kingdom 2.5%
	10,175,965	Cable and Wireless		7,821,841
		Telecommunications Services Provider in the Caribbean
	544,900	PureCircle (a)		4,362,477
		Natural Sweeteners
				12,184,318
		> Kazakhstan 2.2%
	1,268,483	Halyk Savings Bank of Kazakhstan - GDR		10,782,106
		Retail Bank & Insurer in Kazakhstan
		> Sweden 1.8%
	288,064	Hexagon		8,886,642
		Design, Measurement & Visualization Software & Equipment
		> Spain 1.4%
	1,148,390	Prosegur		6,542,696
		Security Guards
		> Italy 1.1%
	393,882	Pirelli		5,312,445
		Global Tire Supplier
		> France 1.1%
	161,154	Eutelsat		5,211,664
		Fixed Satellite Services
		> Finland 1.1%
	290,000	Tikkurila		5,064,974
		Decorative & Industrial Paint in Scandinavia & Central & Eastern Europe

Number of Shares			Value
		> Turkey 0.2%
	54,624	Aviva (a)	$	1,047,064
		Private Pension & Life Insurance Provider
Europe: Total				55,031,909
Latin America 10.8%
		> Brazil 3.8%
	557,970	Localiza Rent A Car		7,495,715
		Car Rental
	1,430,100	Odontoprev		5,304,637
		Dental Insurance
	255,000	Linx		4,844,443
		Retail Management Software in Brazil
	3,663,018	Beadell Resources (a)		663,425
		Gold Mining in Brazil
				18,308,220
		> Mexico 3.8%
	40,525	Grupo Aeroportuario del Sureste - ADR		5,342,816
		Mexican Airport Operator
	2,747,000	Hoteles City Express (a)		4,334,502
		Budget Hotel Operator in Mexico
	2,278,100	Genomma Lab International (a)		4,332,694
		Developer, Marketer & Distributor of Consumer Products
	2,069,000	Qualitas		4,282,793
		Auto Insurer in Mexico & Central America
				18,292,805
		> Chile 1.6%
	1,943,078	Forus		7,941,359
		Multi-brand Latin American Wholesaler & Retailer
		> Colombia 1.6%
	6,047,782	Isagen		7,545,413
		Colombian Electricity Provider
Latin America: Total				52,087,797
Other Countries 8.7%
		> South Africa 7.4%
	2,003,746	Coronation Fund Managers		19,829,832
		South African Fund Manager
	2,851,148	Rand Merchant Insurance		10,070,922
		Directly Sold Property & Casualty Insurance; Holdings in other Insurers
	288,041	Mr. Price		5,826,748
		South African Retailer of Apparel, Household & Sporting Goods
				35,727,502
		> United States 1.1%
	171,094	Bladex		5,149,929
		Latin American Trade Financing House

See accompanying notes to financial statements.

Number of Shares			Value
		> Morocco 0.2%
	4,273	Holcim Maroc	$	897,347
		Cement Player in Morocco
Other Countries: Total				41,774,778
Total Equities: 92.6% (Cost: $429,069,885)				446,616,981	(c)
Short-Term Investments 6.3%
	30,382,894	JPMorgan U.S. Government Money Market Fund, IM Shares (7 day yield of 0.01%)		30,382,894
Total Short-Term Investments: 6.3% (Cost: $30,382,894)				30,382,894

Number of Shares			Value
Securities Lending Collateral 0.7%
	3,292,000	Dreyfus Government Cash Management Fund, Institutional Shares (7 day yield of 0.01%) (d)	$	3,292,000
Total Securities Lending Collateral: 0.7% (Cost: $3,292,000)				3,292,000
Total Investments: 99.6% (Cost: $462,744,779)(e)				480,291,875
Obligation to Return Collateral for Securities Loaned: (0.7)%				(3,292,000	)
Cash and Other Assets Less Liabilities: 1.1%				5,335,232
Net Assets: 100.0%			$	482,335,107

ADR - American Depositary Receipts

GDR - Global Depositary Receipts

> Notes to Statement of Investments

(a) Non-income producing security.

(b) All or a portion of this security was on loan at December 31, 2014. The total market value of securities on loan at December 31, 2014 was $3,111,617.

Currency	Value		Percentage of Net Assets
Hong Kong Dollar	$	56,924,376		11.8
Taiwan Dollar		46,517,830		9.6
U.S. Dollar		41,843,846		8.7
Indonesian Rupiah		39,890,195		8.3
Indian Rupee		39,648,650		8.2
Philippine Peso		37,064,331		7.7
South African Rand		35,727,503		7.4
Other currencies less than 5% of total net assets		149,000,250		30.9
Total Equities	$	446,616,981		92.6

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

(e) At December 31, 2014, for federal income tax purposes, the cost of investments was $465,233,774 and net unrealized appreciation was $15,058,101 consisting of gross unrealized appreciation of $54,270,589 and gross unrealized depreciation of $39,212,488.

Fair Value Measurements

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

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

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

See accompanying notes to financial statements.

Columbia Acorn Emerging Markets Fund^SM

Statement of Investments, continued

> Notes to Statement of Investments

amortized cost. Additionally, securities fair valued by the Valuation Committee (the Committee) of the Fund's Board of Trustees (the Board) that rely on significant observable inputs are also included in Level 2. Typical Level 3 securities include any security fair valued by the Committee that relies on significant unobservable inputs.

Under the direction of the Board, the Committee is responsible for overseeing the valuation procedures approved by the Board.

The following table summarizes the inputs used, as of December 31, 2014, 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
Asia	$	20,568,995	$	277,153,502	$	-	$	297,722,497
Europe		-		55,031,909		-		55,031,909
Latin America		51,424,372		663,425		-		52,087,797
Other Countries		5,149,929		36,624,849		-		41,774,778
Total Equities		77,143,296		369,473,685		-		446,616,981
Total Short-Term Investments		30,382,894		-		-		30,382,894
Total Securities Lending Collateral		3,292,000		-		-		3,292,000
Total Investments	$	110,818,190	$	369,473,685	$	-	$	480,291,875

There were no transfers of financial assets between levels during the period.

See accompanying notes to financial statements.

Columbia Acorn Emerging Markets Fund^SM

Portfolio Diversification

At December 31, 2014, the Fund's portfolio investments as a percentage of net assets were diversified as follows:

	Value		Percentage of Net Assets
> Consumer Goods & Services
Retail	$	79,453,513		16.5
Casinos & Gaming		39,055,619		8.1
Food & Beverage		30,476,900		6.3
Travel		11,830,217		2.4
Consumer Goods Distribution		5,375,990		1.1
Other Durable Goods		5,312,446		1.1
Apparel		4,749,782		1.0
Nondurables		4,332,694		0.9
		180,587,161		37.4
> Information
Instrumentation		16,764,617		3.5
Entertainment Programming		14,554,601		3.0
Business Software		13,731,085		2.8
Satellite Broadcasting & Services		13,217,039		2.8
Internet Related		10,201,699		2.1
Telephone & Data Services		7,821,841		1.6
Semiconductors & Related Equipment		5,663,384		1.2
Telecommunications Equipment		5,314,795		1.1
Computer Hardware & Related Equipment		5,293,043		1.1
Mobile Communications		5,274,828		1.1
Cable TV		4,687,606		1.0
		102,524,538		21.3
> Finance
Banks		21,357,604		4.4
Brokerage & Money Management		19,829,832		4.1
Insurance		19,658,352		4.1
Diversified Financial Companies		1,047,065		0.2
		61,892,853		12.8
> Industrial Goods & Services
Industrial Materials & Specialty Chemicals		28,743,200		6.0
Other Industrial Services		8,744,542		1.8
Outsourcing Services		6,542,696		1.4
Machinery		5,445,253		1.1
		49,475,691		10.3
> Health Care
Pharmaceuticals		18,316,608		3.8
Medical Supplies		10,651,163		2.2
		28,967,771		6.0

	Value			Percentage of Net Assets
> Other Industries
Transportation	$	10,610,009			2.2
Regulated Utilities		7,545,413			1.6
		18,155,422			3.8
> Energy & Minerals
Oil Refining, Marketing & Distribution		4,350,120			0.9
Mining		663,425			0.1
		5,013,545			1.0
Total Equities:		446,616,981			92.6
Short-Term Investments:		30,382,894			6.3
Securities Lending Collateral:		3,292,000			0.7
Total Investments:		480,291,875			99.6
Obligation to Return Collateral for Securities Loaned:		(3,292,000	)		(0.7	)
Cash and Other Assets Less Liabilities:		5,335,232			1.1
Net Assets:	$	482,335,107			100.0

See accompanying notes to financial statements.

Columbia Acorn European Fund^SM

Major Portfolio Changes in the Fourth Quarter (Unaudited)

	Number of Shares
	9/30/14		12/31/14
Purchases
Europe
> United Kingdom
PureCircle		2,222		42,232

	Number of Shares
	9/30/14		12/31/14
Sales
Europe
> United Kingdom
Abcam		101,510		61,730
Aggreko		22,503		16,633
Assura		1,933,560		1,460,625
AVEVA		19,210		16,930
Babcock International		58,070		45,240
Cable and Wireless		726,213		505,313
Cambian		196,680		145,820
Charles Taylor		240,940		188,030
Connect Group		277,770		225,231
Dialight		40,510		31,910
Domino's Pizza UK & Ireland		59,400		37,830
Elementis		133,120		89,680
Fidessa Group		15,610		10,300
Halfords		73,060		49,530
Halma		59,235		38,985
Jardine Lloyd Thompson Group		70,133		40,000
Ocado		110,390		92,240
Polypipe		141,240		100,890
Rightmove		14,880		11,210
RPS Group		128,860		101,810
Shaftesbury		54,000		0
Spirax Sarco		30,750		21,120
WH Smith		47,530		32,210
Whitbread		8,325		5,575
> France
AKKA Technologies		16,283		11,883
Bonduelle		21,430		15,320
Cegedim		21,040		14,480
Eurofins Scientific		3,230		2,390
Eutelsat		17,160		12,505
Hi-Media		170,400		123,020
Neopost		23,030		16,720
Norbert Dentressangle		3,740		2,690
Saft		16,651		12,681
> Germany
Aurelius		32,530		22,450
Elringklinger		19,110		12,580
MTU Aero Engines		6,950		4,410
NORMA Group		27,290		16,790
Rational		1,910		1,240
TAG Immobilien		9,829		0
Telefonica Deutschland		112,250		80,330
Wirecard		20,890		14,240

See accompanying notes to financial statements.

	Number of Shares
	9/30/14		12/31/14
Sales (continued)
Europe—continued
> Sweden
Hexagon		29,450		18,910
Mekonomen		21,070		16,400
Recipharm		40,490		28,950
Sweco		43,610		31,870
Swedish Match		25,880		19,320
Unibet		11,111		7,351
> Spain
Bolsas y Mercados Españoles		14,590		10,370
DIA		145,730		123,060
Prosegur		109,520		100,660
Viscofan		15,040		10,000
> Switzerland
Geberit		3,480		2,290
INFICON		1,820		1,250
Partners Group		4,280		3,570
Sika		160		0
> Netherlands
Aalberts Industries		35,710		26,960
Arcadis		14,179		11,819
Brunel		18,101		16,071
Core Labs		3,610		1,960
Gemalto		6,180		4,760
> Finland
Konecranes		16,520		12,580
Munksjo		70,810		63,850
Sponda		131,300		101,200
Tikkurila		31,721		25,341
> Norway
Atea		42,030		32,400
Orkla		67,850		58,530
Subsea 7		38,130		33,440
> Italy
IMA		16,450		10,240
Pirelli		39,720		29,520
> Denmark
Jyske Bank		9,790		7,260
SimCorp		22,580		15,490
> Belgium
EVS Broadcast Equipment		12,520		10,920
> Austria
Schoeller-Bleckmann		5,770		0

	Number of Shares
	9/30/14		12/31/14
Other Countries
> United States
Gulfmark Offshore		1,637		0

See accompanying notes to financial statements.

Columbia Acorn European Fund^SM

Statement of Investments, December 31, 2014

Number of Shares			Value
			Equities: 95.7%
Europe 95.7%
		> United Kingdom 33.2%
	1,460,625	Assura	$	1,161,031
		Primary Health Care Property Developer
	21,120	Spirax Sarco		940,196
		Steam Systems for Manufacturing & Processing Industries
	45,240	Babcock International		741,134
		Public Sector Outsourcer
	188,030	Charles Taylor		732,659
		Insurance Services
	32,210	WH Smith		673,565
		Newsprint, Books & General Stationery Retailer
	92,240	Ocado (a)(b)		570,957
		Online Grocery Retailer
	40,000	Jardine Lloyd Thompson Group		558,603
		International Business Insurance Broker
	225,231	Connect Group		537,604
		Newspaper & Magazine Distributor
	145,820	Cambian (a)		462,874
		Mental Health Facilities & Programs
	61,730	Abcam		448,109
		Online Sales of Antibodies
	38,985	Halma		415,266
		Health & Safety Sensor Technology
	37,830	Domino's Pizza UK & Ireland		413,043
		Pizza Delivery in the UK, Ireland & Germany
	5,575	Whitbread		412,585
		UK Hotelier & Coffee Shop
	31,910	Dialight		402,853
		LED Products for Hazardous & Industrial Environments
	11,210	Rightmove		390,928
		Internet Real Estate Listings
	505,313	Cable and Wireless		388,413
		Telecommunications Services Provider in the Caribbean
	16,633	Aggreko		387,882
		Temporary Power & Temperature Control Services
	100,890	Polypipe		386,029
		Manufacturer of Plastic Piping & Fittings
	10,300	Fidessa Group		383,681
		Software for Financial Trading Systems
	89,680	Elementis		363,515
		Specialty Chemicals
	49,530	Halfords		361,435
		UK Retailer for Leisure Goods & Auto Parts
	16,930	AVEVA		346,727
		Engineering Software
	42,232	PureCircle (a)		338,110
		Natural Sweeteners

Number of Shares			Value
	101,810	RPS Group	$	331,802
		Consultant Specializing in Energy, Water, Urban Planning, Health & Safety
				12,149,001
		> France 12.0%
	16,720	Neopost		953,839
		Postage Meter Machines
	2,390	Eurofins Scientific		610,053
		Food, Pharmaceuticals & Materials Screening & Testing
	14,480	Cegedim (a)		511,278
		Medical Market Research/IT Services
	11,883	AKKA Technologies		416,417
		Engineering Consultancy
	12,505	Eutelsat		404,407
		Fixed Satellite Services
	2,690	Norbert Dentressangle		396,499
		European Logistics & Transport Group
	12,681	Saft		384,642
		Niche Battery Manufacturer
	15,320	Bonduelle		371,040
		Producer of Canned, Deep-frozen & Fresh Vegetables
	123,020	Hi-Media (a)		369,132
		Online Advertiser in Europe
				4,417,307
		> Germany 10.6%
	22,450	Aurelius		849,646
		European Turnaround Investor
	16,790	NORMA Group		801,403
		Clamps for Automotive & Industrial Applications
	14,240	Wirecard		620,923
		Online Payment Processing & Risk Management
	12,580	Elringklinger		434,961
		Automobile Components
	80,330	Telefonica Deutschland		425,737
		Mobile & Fixed-line Communications in Germany
	1,240	Rational		388,535
		Commercial Ovens
	4,410	MTU Aero Engines		383,254
		Airplane Engine Components & Services
				3,904,459
		> Sweden 8.2%
	19,320	Swedish Match		605,383
		Swedish Snus
	18,910	Hexagon		583,365
		Design, Measurement & Visualization Software & Equipment
	28,950	Recipharm (a)		499,487
		Contract Development Manufacturing Organization
	7,351	Unibet		464,415
		European Online Gaming Operator
	31,870	Sweco		433,352
		Engineering Consultants

See accompanying notes to financial statements.

Number of Shares			Value
		> Sweden—continued
	16,400	Mekonomen	$	427,874
		Nordic Integrated Wholesaler/Retailer of Automotive Parts & Service
				3,013,876
		> Spain 6.4%
	123,060	DIA		833,864
		Discount Retailer in Spain & Latin America
	100,660	Prosegur		573,488
		Security Guards
	10,000	Viscofan		530,563
		Sausage Casings Maker
	10,370	Bolsas y Mercados Españoles		401,634
		Spanish Stock Markets
				2,339,549
		> Switzerland 6.0%
	3,570	Partners Group		1,038,646
		Private Markets Asset Management
	2,290	Geberit		774,714
		Plumbing Supplies
	1,250	INFICON		387,560
		Gas Detection Instruments
				2,200,920
		> Netherlands 5.6%
	26,960	Aalberts Industries		795,079
		Flow Control & Heat Treatment
	4,760	Gemalto		388,475
		Digital Security Solutions
	11,819	Arcadis		354,483
		Engineering Consultants
	16,071	Brunel		263,166
		Temporary Specialist & Energy Staffing
	1,960	Core Labs (b)		235,866
		Oil & Gas Reservoir Consulting
				2,037,069
		> Finland 5.3%
	54,850	Munksjo (a)(b)		594,023
	9,000	Munksjo (a)(c)		98,710
		Specialty Paper Maker
	25,341	Tikkurila		442,591
		Decorative & Industrial Paint in Scandinavia & Central & Eastern Europe
	101,200	Sponda		440,508
		Office, Retail & Logistics Properties
	12,580	Konecranes		359,727
		Manufacture & Service of Industrial Cranes & Port Handling Equipment
				1,935,559
		> Norway 2.9%
	58,530	Orkla		398,441
		Food & Brands, Aluminum, Chemicals Conglomerate

Number of Shares			Value
	33,440	Subsea 7	$	342,188
		Offshore Subsea Contractor
	32,400	Atea		334,738
		Nordic IT Hardware/Software Reseller & Installation Company
				1,075,367
		> Italy 2.3%
	10,240	IMA		447,502
		Food & Drugs Packaging & Machinery
	29,520	Pirelli		398,148
		Global Tire Supplier
				845,650
		> Denmark 2.1%
	15,490	SimCorp		408,977
		Software for Investment Managers
	7,260	Jyske Bank (a)		366,967
		Danish Bank
				775,944
		> Belgium 1.1%
	10,920	EVS Broadcast Equipment		394,267
		Digital Live Mobile Production Software & Systems
Europe: Total				35,088,968
Total Equities: 95.7% (Cost: $34,661,015)				35,088,968	(d)
Short-Term Investments 5.6%
	2,049,263	JPMorgan U.S. Government Money Market Fund, IM Shares (7 day yield of 0.01%)		2,049,263
Total Short-Term Investments: 5.6% (Cost: $2,049,263)				2,049,263
Securities Lending Collateral 2.6%
	940,969	Dreyfus Government Cash Management Fund, Institutional Shares (7 day yield of 0.01%) (e)		940,969
Total Securities Lending Collateral: 2.6% (Cost: $940,969)				940,969
Total Investments: 103.9% (Cost: $37,651,247)(f)				38,079,200
Obligation to Return Collateral for Securities Loaned: (2.6)%				(940,969	)
Cash and Other Assets Less Liabilities: (1.3)%				(505,423	)
Net Assets: 100.0%			$	36,632,808

See accompanying notes to financial statements.

Columbia Acorn European Fund^SM

Statement of Investments, continued

> Notes to Statement of Investments

(a) Non-income producing security.

(b) All or a portion of this security was on loan at December 31, 2014. The total market value of securities on loan at December 31, 2014 was $899,714.

(d) On December 31, 2014, the Fund's total equity investments were denominated in currencies as follows:

Currency	Value		Percentage of Net Assets
Euro	$	15,539,284		42.3
British Pound		12,149,001		33.2
Swedish Krona		3,112,586		8.5
Swiss Franc		2,200,920		6.0
Other currencies less than 5% of total net assets		2,087,177		5.7
Total Equities	$	35,088,968		95.7

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

(f) At December 31, 2014, for federal income tax purposes, the cost of investments was $38,033,522 and net unrealized appreciation was $45,678 consisting of gross unrealized appreciation of $2,648,480 and gross unrealized depreciation of $2,602,802.

Fair Value Measurements

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

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

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

Under the direction of the Board, the Committee is responsible for overseeing the valuation procedures approved by the Board.

See accompanying notes to financial statements.

> Notes to Statement of Investments

The following table summarizes the inputs used, as of December 31, 2014, 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
Europe	$	235,866	$	34,853,102	$	-	$	35,088,968
Total Equities		235,866		34,853,102		-		35,088,968
Total Short-Term Investments		2,049,263		-		-		2,049,263
Total Securities Lending Collateral		940,969		-		-		940,969
Total Investments	$	3,226,098	$	34,853,102	$	-	$	38,079,200

There were no transfers of financial assets between levels during the period.

See accompanying notes to financial statements.

Columbia Acorn European Fund^SM

Portfolio Diversification

At December 31, 2014, the Fund's portfolio investments as a percentage of net assets were diversified as follows:

	Value		Percentage of Net Assets
> Industrial Goods & Services
Machinery	$	4,278,763		11.7
Other Industrial Services		2,500,826		6.8
Conglomerates		2,043,166		5.6
Outsourcing Services		1,994,205		5.4
Industrial Materials & Specialty Chemicals		1,933,800		5.3
Construction		1,160,743		3.2
Electrical Components		787,495		2.1
		14,698,998		40.1
> Consumer Goods & Services
Retail		2,867,696		7.8
Food & Beverage		1,845,096		5.0
Restaurants		825,627		2.2
Consumer Goods Distribution		537,604		1.5
Casinos & Gaming		464,415		1.3
Other Durable Goods		398,148		1.1
		6,938,586		18.9
> Information
Business Software		1,722,749		4.7
Computer Services		846,016		2.3
Telephone & Data Services		814,150		2.2
Computer Hardware & Related Equipment		782,743		2.2
Financial Processors		620,923		1.7
Instrumentation		415,266		1.1
Satellite Broadcasting & Services		404,407		1.1
Internet Related		390,928		1.1
Advertising		369,132		1.0
		6,366,314		17.4
> Finance
Insurance		1,291,262		3.5
Brokerage & Money Management		1,038,646		2.9
Financial Processors		401,634		1.1
Banks		366,967		1.0
		3,098,509		8.5
> Other Industries
Real Estate		1,601,539		4.4
Transportation		396,498		1.1
		1,998,037		5.5
> Health Care
Pharmaceuticals		499,487		1.3
Health Care Services		462,874		1.3
Medical Supplies		448,109		1.2
		1,410,470		3.8

	Value			Percentage of Net Assets
> Energy & Minerals
Oil Services	$	342,188			0.9
Mining		235,866			0.6
		578,054			1.5
Total Equities:		35,088,968			95.7
Short-Term Investments:		2,049,263			5.6
Securities Lending Collateral:		940,969			2.6
Total Investments:		38,079,200			103.9
Obligation to Return Collateral for Securities Loaned:		(940,969	)		(2.6	)
Cash and Other Assets Less Liabilities:		(505,423	)		(1.3	)
Net Assets:	$	36,632,808			100.0

See accompanying notes to financial statements.

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Columbia Acorn Family of Funds

Statements of Assets and Liabilities

December 31, 2014	Columbia Acorn® Fund			Columbia Acorn International®			Columbia Acorn USA®			Columbia Acorn International Select^SM
Assets:
Unaffiliated investments, at cost	$	7,484,551,196		$	6,181,672,054		$	830,347,077		$	226,743,851
Affiliated investments, at cost		1,936,450,819			89,062,228			—			—
Unaffiliated investments, at value (including securities on loan: Columbia Acorn Fund $517,888,630; Columbia Acorn International $101,872,493; Columbia Acorn USA $76,216,239; Columbia Acorn International Select $5,229,212; Columbia Acorn Select $25,021,001; Columbia Thermostat Fund $—; Columbia Acorn Emerging Markets Fund $3,111,617; Columbia Acorn European Fund $899,714)	$	13,330,324,037		$	7,706,200,251		$	1,481,414,096		$	247,542,120
Affiliated investments, at value		3,181,183,473			82,210,773			—			—
Foreign currency (cost: Columbia Acorn Fund $—; Columbia Acorn International $60,590; Columbia Acorn USA $—; Columbia Acorn International Select $207; Columbia Acorn Select $—; Columbia Thermostat Fund $—; Columbia Acorn Emerging Markets Fund $8,175; Columbia Acorn European Fund $—)		—			60,626			—			194
Receivable for:
Investments sold		85,134,157			10,721,096			5,422,076			—
Investments sold on a delayed delivery basis		—			28,140,540			—			10,544,973
Fund shares sold		6,362,703			11,502,927			595,653			1,297,160
Dividends		9,179,988			8,261,684			663,335			476,654
Interest		—			422,108			—			158,175
Securities lending income		733,110			92,922			42,518			2,959
Foreign tax reclaims		80,119			5,793,287			—			202,691
Expense reimbursement due from Investment Manager		—			1,105			—			—
Trustees' deferred compensation plan		3,633,077			1,162,700			311,353			—
Prepaid expenses		178,504			78,612			14,603			3,123
Other assets		—			—			—			39
Total Assets		16,616,809,168			7,854,648,631			1,488,463,634			260,228,088
Liabilities:
Collateral on securities loaned		534,041,419			105,532,274			78,364,950			5,507,307
Unrealized depreciation on forward foreign currency exchange contracts		—			—			—			97,181
Payable for:
Investments purchased		13,139,136			1,485			20,461			—
Fund shares redeemed		126,071,938			11,472,191			12,027,290			1,511,773
Investment advisory fee		285,004			160,731			33,671			6,576
Administration fee		17,109			8,193			1,501			270
12b-1 Service and Distribution fees		40,545			9,574			2,081			602
Reports to shareholders		522,549			371,066			57,308			23,093
Transfer agent fees		2,795,822			940,762			350,629			31,788
Trustees' fees		6,459			3,535			315			58,916
Custody fees		75,578			446,078			3,972			15,091
Professional fee		279,984			172,371			60,976			49,286
Chief compliance officer expenses		67,227			29,269			5,346			1,209
Deferred foreign capital gains tax payable		1,217,682			771,879			—			—
Trustees' deferred compensation plan		3,633,077			1,162,700			311,353			—
Other liabilities		39,614			88,388			7,494			5,296
Total Liabilities		682,233,143			121,170,496			91,247,347			7,308,388
Net Assets	$	15,934,576,025		$	7,733,478,135		$	1,397,216,287		$	252,919,700
Composition of Net Assets:
Paid-in capital	$	8,251,610,741		$	6,284,036,774		$	713,240,383		$	247,521,085
Undistributed (Overdistributed) net investment income (loss)		(3,615,764	)		(92,376,083	)		(312,115	)		(6,492,720	)
Accumulated net realized gain (loss)		597,304,435			25,535,899			33,221,000			(8,784,944	)
Net unrealized appreciation (depreciation) on:
Unaffiliated investments		5,845,772,841			1,524,528,197			651,067,019			20,798,269
Affiliated investments		1,244,732,654			(6,851,455	)		—			—
Foreign currency translations		(11,200	)		(623,318	)		—			(24,809	)
Forward foreign currency exchange contracts		—			—			—			(97,181	)
Foreign capital gains tax		(1,217,682	)		(771,879	)		—			—
Net Assets	$	15,934,576,025		$	7,733,478,135		$	1,397,216,287		$	252,919,700
Net asset value per share – Class A (a)	$	30.30		$	41.68		$	29.13		$	22.04
(Net assets/shares)	($	2,694,610,293/ 88,936,087)		($	946,553,332/ 22,709,158)		($	148,089,203/ 5,084,062)		($	53,419,289/ 2,424,210)
Maximum offering price per share – Class A (b)	$	32.15		$	44.22		$	30.91		$	23.38
(Net asset value per share/front-end sales charge)		($30.30/0.9425)			($41.68/0.9425)			($29.13/0.9425)			($22.04/0.9425)
Net asset value and offering price per share – Class B (a)	$	26.53		$	40.38		$	25.27		$	20.69
(Net assets/shares)	($	7,201,444/ 271,438)		($	6,515,645/ 161,339)		($	233,839/ 9,255)		($	355,261/ 17,168)
Net asset value and offering price per share – Class C (a)	$	25.92		$	40.20		$	24.98		$	20.54
(Net assets/shares)	($	776,369,920/ 29,952,465)		($	103,691,126/ 2,579,547)		($	36,475,846/ 1,460,419)		($	8,057,482/ 392,206)
Net asset value and offering price per share – Class I (c)	$	32.03		$	41.76		$	31.19	(d)	$	22.29	(d)
(Net assets/shares)	($	28,164,333/ 879,375)		($	38,804,103/ 929,209)			($2,190/70)			($2,054/92)
Net asset value and offering price per share – Class R (c)	$	—		$	41.67		$	—		$	—
(Net assets/shares)	($	—/—	)	($	5,560,256/ 133,428)		($	—/—	)	($	—/—	)
Net asset value and offering price per share – Class R4 (c)	$	32.51		$	42.02		$	31.70		$	22.45
(Net assets/shares)	($	250,456,683/ 7,704,621)		($	424,424,543/ 10,100,805)		($	7,951,752/ 250,822)		($	973,923/ 43,382)
Net asset value and offering price per share – Class R5 (c)	$	32.55		$	41.71		$	31.71		$	22.43
(Net assets/shares)	($	458,223,180/ 14,079,444)		($	397,881,832/ 9,540,352)		($	36,689,268/ 1,156,852)		($	2,592,742/ 115,594)
Net asset value and offering price per share – Class Y (c)	$	32.61		$	42.02		$	31.80		$	22.42
(Net assets/shares)	($	378,779,713/ 11,616,665)		($	225,012,495/ 5,354,548)		($	35,550,879/ 1,118,012)		($	11,755,060/ 524,405)
Net asset value and offering price per share – Class Z (c)	$	31.95		$	41.73		$	31.03		$	22.30
(Net assets/shares)	($	11,340,770,459/ 354,923,558)		($	5,585,034,803/ 133,844,433)		($	1,132,223,310/ 36,489,177)		($	175,763,889/ 7,883,319)

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

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

(d) Net asset value per share rounds to this amount due to fractional shares outstanding.

See accompanying notes to financial statements.

December 31, 2014	Columbia Acorn Select^SM			Columbia Thermostat Fund^SM			Columbia Acorn Emerging Markets Fund^SM			Columbia Acorn European Fund^SM
Assets:
Unaffiliated investments, at cost	$	465,246,337		$	5,937,697		$	462,744,779		$	37,651,247
Affiliated investments, at cost		23,207,419			1,217,734,045			—			—
Unaffiliated investments, at value (including securities on loan: Columbia Acorn Fund $517,888,630; Columbia Acorn International $101,872,493; Columbia Acorn USA $76,216,239; Columbia Acorn International Select $5,229,212; Columbia Acorn Select $25,021,001; Columbia Thermostat Fund $—; Columbia Acorn Emerging Markets Fund $3,111,617; Columbia Acorn European Fund $899,714)	$	692,641,201		$	5,937,697		$	480,291,875		$	38,079,200
Affiliated investments, at value		2,231,409			1,254,039,602			—			—
Foreign currency (cost: Columbia Acorn Fund $—; Columbia Acorn International $60,590; Columbia Acorn USA $—; Columbia Acorn International Select $207; Columbia Acorn Select $—; Columbia Thermostat Fund $—; Columbia Acorn Emerging Markets Fund $8,175; Columbia Acorn European Fund $—)		—			—			8,175			—
Receivable for:
Investments sold		2,733,151			—			5,671,005			—
Investments sold on a delayed delivery basis		—			—			1,410,304			—
Fund shares sold		327,811			3,252,825			502,063			106,968
Dividends		505,390			2,517,967			381,411			19,807
Interest		—			—			21,155			—
Securities lending income		5,915			—			4,273			258
Foreign tax reclaims		—			—			16,018			29,146
Expense reimbursement due from Investment Manager		5			272			—			361
Trustees' deferred compensation plan		327,425			—			—			—
Prepaid expenses		6,689			11,441			5,396			604
Other assets		—			—			—			6,700
Total Assets		698,778,996			1,265,759,804			488,311,675			38,243,044
Liabilities:
Collateral on securities loaned		25,598,975			—			3,292,000			940,969
Unrealized depreciation on forward foreign currency exchange contracts		—			—			—			—
Payable for:
Investments purchased		—			2,517,967			392,506			—
Fund shares redeemed		6,049,874			2,509,156			1,341,057			594,520
Investment advisory fee		15,817			3,456			13,868			1,213
Administration fee		717			1,332			508			39
12b-1 Service and Distribution fees		3,202			14,207			2,227			287
Reports to shareholders		51,558			60,626			35,164			9,851
Transfer agent fees		89,370			123,723			87,433			4,879
Trustees' fees		115			68,313			13,396			2,030
Custody fees		2,661			772			67,822			8,105
Professional fee		53,695			36,711			51,847			44,953
Chief compliance officer expenses		2,553			4,188			1,920			230
Deferred foreign capital gains tax payable		—			—			670,775			—
Trustees' deferred compensation plan		327,425			—			—			—
Other liabilities		6,248			6,292			6,045			3,160
Total Liabilities		32,202,210			5,346,743			5,976,568			1,610,236
Net Assets	$	666,576,786		$	1,260,413,061		$	482,335,107		$	36,632,808
Composition of Net Assets:
Paid-in capital	$	412,071,005		$	1,203,792,209		$	483,175,584		$	38,729,584
Undistributed (Overdistributed) net investment income (loss)		(325,960	)		1,675,197			(2,486,157	)		199,170
Accumulated net realized gain (loss)		48,412,887			18,640,098			(15,220,290	)		(2,720,678	)
Net unrealized appreciation (depreciation) on:
Unaffiliated investments		227,394,864			—			17,547,096			427,953
Affiliated investments		(20,976,010	)		36,305,557			—			—
Foreign currency translations		—			—			(10,351	)		(3,221	)
Forward foreign currency exchange contracts		—			—			—			—
Foreign capital gains tax		—			—			(670,775	)		—
Net Assets	$	666,576,786		$	1,260,413,061		$	482,335,107		$	36,632,808
Net asset value per share – Class A (a)	$	21.03		$	14.86		$	12.72		$	14.34
(Net assets/shares)	($	264,233,793/ 12,564,179)		($	450,258,215/ 30,296,730)		($	160,969,366/ 12,653,450)		($	21,100,546/ 1,471,542)
Maximum offering price per share – Class A (b)	$	22.31		$	15.77		$	13.50		$	15.21
(Net asset value per share/front-end sales charge)		($21.03/0.9425)			($14.86/0.9425)			($12.72/0.9425)			($14.34/0.9425)
Net asset value and offering price per share – Class B (a)	$	18.03		$	14.97		$	—		$	—
(Net assets/shares)	($	1,013,740/ 56,223)		($	1,230,725/ 82,215)		($	—/—	)	($	—/—	)
Net asset value and offering price per share – Class C (a)	$	17.69		$	14.96		$	12.65		$	14.16
(Net assets/shares)	($	48,590,843/ 2,746,875)		($	404,455,852/ 27,029,504)		($	41,207,804/ 3,256,664)		($	5,095,696/ 359,769)
Net asset value and offering price per share – Class I (c)	$	22.38		$	—		$	12.75		$	14.33	(d)
(Net assets/shares)	($	18,718,451/ 836,207)		($	—/—	)		($2,537/199)			($2,405/168)
Net asset value and offering price per share – Class R (c)	$	—		$	—		$	—		$	—
(Net assets/shares)	($	—/—	)	($	—/—	)	($	—/—	)	($	—/—	)
Net asset value and offering price per share – Class R4 (c)	$	22.75		$	14.74		$	12.83		$	14.40
(Net assets/shares)	($	1,192,845/ 52,437)		($	23,412,262/ 1,588,161)		($	15,467,392/ 1,205,718)		($	302,200/ 20,989)
Net asset value and offering price per share – Class R5 (c)	$	22.78		$	14.75		$	12.82		$	14.47
(Net assets/shares)	($	10,696,533/ 469,631)		($	3,535,754/ 239,636)		($	19,632,386/ 1,531,295)		($	1,632,907/ 112,858)
Net asset value and offering price per share – Class Y (c)	$	22.86		$	14.74		$	12.71	(d)	$	—
(Net assets/shares)	($	3,643,794/ 159,383)		($	401,249/ 27,225)		($2,409/190)			($	—/—	)
Net asset value and offering price per share – Class Z (c)	$	22.28		$	14.67		$	12.74		$	14.34
(Net assets/shares)	($	318,486,787/ 14,295,229)		($	377,119,004/ 25,702,685)		($	245,053,213/ 19,227,983)		($	8,499,054/ 592,721)

See accompanying notes to financial statements.

Columbia Acorn Family of Funds

Statements of Operations For the Year Ended December 31, 2014

	Columbia Acorn® Fund			Columbia Acorn International®			Columbia Acorn USA®			Columbia Acorn International Select^SM
Investment Income:
Dividends	$	130,103,964		$	193,185,949		$	10,988,172		$	9,293,543
Dividends from affiliates		29,184,960			2,716,857			—			—
Dividends from affiliated investment company shares		—			—			—			—
Interest		28			422,120			—			159,496
Income from securities lending – net		8,813,015			2,698,509			695,151			82,125
		168,101,967			199,023,435			11,683,323			9,535,164
Foreign taxes withheld		(3,690,111	)		(21,512,877	)		(48,111	)		(983,827	)
Total Investment Income		164,411,856			177,510,558			11,635,212			8,551,337
Expenses:
Investment advisory fee		123,279,339			62,943,042			13,670,928			3,181,739
Administration fee		7,213,744			3,125,021			594,093			126,805
12b-1 Service and Distribution fees:
Class A		8,592,952			2,667,608			449,365			175,936
Class B		90,223			72,788			2,594			4,608
Class C		8,701,253			1,126,925			380,797			100,087
Class R		—			31,579			—			—
Transfer agent fees:
Class A		4,155,458			1,720,019			261,824			87,589
Class B		35,903			38,766			1,980			1,679
Class C		600,799			149,726			22,804			13,942
Class R		—			17,366			—			—
Class R4		141,867			727,781			9,607			1,027
Class R5		270,303			180,234			12,947			1,140
Class Z		10,876,663			4,859,090			1,792,440			189,839
Trustees' fees		783,134			331,507			64,051			18,370
Custody fees		286,646			1,627,706			18,109			53,691
Registration and blue sky fees		161,921			208,490			101,054			96,305
Reports to shareholders		1,709,475			1,468,212			189,682			93,133
Audit fees		128,015			186,886			47,454			67,565
Legal fees		954,344			411,735			77,560			16,867
Chief compliance officer expenses		832,923			349,613			67,861			14,459
Other expenses		500,991			432,540			52,183			29,423
Total Expenses		169,315,953			82,676,634			17,817,333			4,274,204
Less reimbursement of expenses by Investment Manager		—			(452,267	)		—			—
Net Expenses		169,315,953			82,224,367			17,817,333			4,274,204
Net Investment Income (Loss)		(4,904,097	)		95,286,191			(6,182,121	)		4,277,133
Net Realized and Unrealized Gain (Loss) on Investments:
Net realized gain (loss) on:
Unaffiliated investments		2,437,002,117			484,607,306			257,777,850			26,013,036
Affiliated investments		821,706,250			(17,504,372	)		—			—
Distributions from affiliated investment company shares		—			—			—			—
Foreign currency translations		(364,125	)		(3,712,183	)		—			(216,519	)
Forward foreign currency exchange contracts		—			—			—			469,034
Net realized gain (loss)		3,258,344,242			463,390,751			257,777,850			26,265,551
Net change in net unrealized appreciation (depreciation) on:
Unaffiliated investments		(2,177,683,907	)		(907,336,120	)		(207,204,706	)		(49,975,163	)
Affiliated investments		(983,776,070	)		(8,117,487	)		—			—
Foreign currency translations		(52,735	)		(768,255	)		—			(22,087	)
Forward foreign currency exchange contracts		—			—			—			(162,999	)
Unaffiliated options		—			—			—			(985,539	)
Affiliated options		—			(2,630,029	)		—			—
Foreign capital gains tax		(1,217,682	)		(771,879	)		—			—
Net change in unrealized appreciation (depreciation)		(3,162,730,394	)		(919,623,770	)		(207,204,706	)		(51,145,788	)
Net realized and unrealized gain (loss)		95,613,848			(456,233,019	)		50,573,144			(24,880,237	)
Net Increase (Decrease) in Net Assets from Operations	$	90,709,751		$	(360,946,828	)	$	44,391,023		$	(20,603,104	)

(a) Class R4 shares reflect activity for the period from June 25, 2014 (commencement of operations) through December 31, 2014.

See accompanying notes to financial statements.

	Columbia Acorn Select^SM			Columbia Thermostat Fund^SM			Columbia Acorn Emerging Markets Fund^SM			Columbia Acorn European Fund^SM
Investment Income:
Dividends	$	5,569,610		$	383		$	11,155,771		$	1,403,275
Dividends from affiliates		—			—			—			—
Dividends from affiliated investment company shares		—			30,848,823			—			—
Interest		—			—			21,163			17
Income from securities lending – net		48,463			—			147,926			7,066
		5,618,073			30,849,206			11,324,860			1,410,358
Foreign taxes withheld		(10,148	)		—			(1,119,841	)		(148,567	)
Total Investment Income		5,607,925			30,849,206			10,205,019			1,261,791
Expenses:
Investment advisory fee		6,450,443			1,290,957			5,370,711			590,149
Administration fee		285,780			483,999			194,491			18,574
12b-1 Service and Distribution fees:
Class A		737,403			1,212,958			516,453			71,873
Class B		13,589			12,184			—			—
Class C		554,669			4,156,486			414,504			40,802
Class R		—			—			—			—
Transfer agent fees:
Class A		353,825			358,522			225,183			30,394
Class B		8,093			3,500			—			—
Class C		51,781			305,697			49,236			5,171
Class R		—			—			—			—
Class R4		2,424			13,427			10,924			136	(a)
Class R5		5,531			1,132			10,150			944
Class Z		329,934			220,537			283,809			15,080
Trustees' fees		32,033			52,035			24,337			3,067
Custody fees		8,718			1,735			245,329			52,875
Registration and blue sky fees		100,823			143,059			105,558			81,031
Reports to shareholders		169,234			255,154			148,357			36,112
Audit fees		47,454			35,914			69,614			36,644
Legal fees		36,715			62,378			29,416			3,019
Chief compliance officer expenses		32,246			53,583			21,819			2,257
Other expenses		60,146			44,174			55,010			16,407
Total Expenses		9,280,841			8,707,431			7,774,901			1,004,535
Less reimbursement of expenses by Investment Manager		(854	)		(135,531	)		—			(147,638	)
Net Expenses		9,279,987			8,571,900			7,774,901			856,897
Net Investment Income (Loss)		(3,672,062	)		22,277,306			2,430,118			404,894
Net Realized and Unrealized Gain (Loss) on Investments:
Net realized gain (loss) on:
Unaffiliated investments		158,812,494			35			(9,031,194	)		(2,662,856	)
Affiliated investments		(5,568,755	)		22,954,871			—			—
Distributions from affiliated investment company shares		—			15,223,291			—			—
Foreign currency translations		(10,222	)		—			(198,212	)		(50,072	)
Forward foreign currency exchange contracts		—			—			—			—
Net realized gain (loss)		153,233,517			38,178,197			(9,229,406	)		(2,712,928	)
Net change in net unrealized appreciation (depreciation) on:
Unaffiliated investments		(133,989,051	)		—			(13,842,360	)		(3,112,977	)
Affiliated investments		854,842			4,982,086			—			—
Foreign currency translations		—			—			4,051			(3,732	)
Forward foreign currency exchange contracts		—			—			—			—
Unaffiliated options		—			—			(131,808	)		—
Affiliated options		—			—			—			—
Foreign capital gains tax		—			—			(670,775	)		—
Net change in unrealized appreciation (depreciation)		(133,134,209	)		4,982,086			(14,640,892	)		(3,116,709	)
Net realized and unrealized gain (loss)		20,099,308			43,160,283			(23,870,298	)		(5,829,637	)
Net Increase (Decrease) in Net Assets from Operations	$	16,427,246		$	65,437,589		$	(21,440,180	)	$	(5,424,743	)

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®						Columbia Acorn International Select^SM
Increase (Decrease) in Net Assets	Year ended December 31,						Year ended December 31,						Year ended December 31,						Year ended December 31,
	2014			2013			2014			2013			2014			2013			2014			2013
Operations:
Net investment income (loss)	$	(4,904,097	)	$	5,803,936		$	95,286,191		$	94,506,163		$	(6,182,121	)	$	(4,042,574	)	$	4,277,133		$	4,636,217
Net realized gain (loss) on investments, foreign currency translations, forward foreign currency exchange contracts and foreign capital gains tax		2,436,637,992			1,401,573,106			480,895,123			523,273,919			257,777,850			160,973,633			26,265,551			29,669,962
Net realized gain (loss) on affiliated investments and distributions from affiliated investment company shares		821,706,250			222,109,404			(17,504,372	)		76,804,823			—			—			—			—
Net change in net unrealized appreciation (depreciation) on investments, foreign currency translations, forward foreign currency exchange contracts, options and foreign capital gains tax		(2,178,954,324	)		2,882,264,973			(908,876,254	)		906,950,318			(207,204,706	)		306,146,936			(51,145,788	)		13,943,403
Net change in net unrealized appreciation (depreciation) on affiliated investments, affiliated options and affiliated investment company shares		(983,776,070	)		742,076,449			(10,747,516	)		(67,324,444	)		—			392,095			—			—
Net Increase (Decrease) in Net Assets from Operations		90,709,751			5,253,827,868			(360,946,828	)		1,534,210,779			44,391,023			463,470,090			(20,603,104	)		48,249,582
Distributions to Shareholders From:
Net investment income – Class A		—			(4,469,883	)		(11,982,984	)		(25,492,504	)		—			—			(224,613	)		(995,831	)
Net realized gain – Class A		(486,737,575	)		(242,979,462	)		(51,297,757	)		(42,739,072	)		(28,022,455	)		(16,332,703	)		(6,609,718	)		(5,217,634	)
Net investment income – Class B		—			—			(33,111	)		(249,782	)		—			—			—			(6,430	)
Net realized gain – Class B		(1,499,818	)		(1,474,831	)		(404,076	)		(556,329	)		(50,293	)		(57,712	)		(51,627	)		(67,482	)
Net investment income – Class C		—			—			(500,190	)		(1,667,787	)		—			—			—			(60,907	)
Net realized gain – Class C		(148,638,681	)		(65,282,509	)		(5,765,804	)		(4,540,816	)		(7,386,824	)		(3,645,977	)		(1,052,637	)		(740,564	)
Net investment income – Class I		—			(44,509	)		(432,624	)		(1,200,147	)		—			—			(19	)		(44	)
Net realized gain – Class I		(3,521,541	)		(1,462,421	)		(1,776,863	)		(1,173,000	)		(424	)		(310	)		(267	)		(183	)
Net investment income – Class R		—			—			(45,702	)		(88,738	)		—			—			—			—
Net realized gain – Class R		—			—			(308,877	)		(220,182	)		—			—			—			—
Net investment income – Class R4		—			(39,853	)		(5,947,002	)		(5,132,184	)		—			—			(7,289	)		(6,112	)
Net realized gain – Class R4		(21,919,022	)		(3,609,537	)		(21,064,501	)		(13,386,984	)		(1,294,173	)		(464,529	)		(123,308	)		(20,623	)
Net investment income – Class R5		—			(132,214	)		(6,469,747	)		(6,226,444	)		—			—			(19,269	)		(15,307	)
Net realized gain – Class R5		(83,114,711	)		(24,670,758	)		(20,627,952	)		(11,061,862	)		(5,923,118	)		(450,508	)		(294,842	)		(50,485	)
Net investment income – Class Y		—			(1,014,881	)		(3,631,416	)		(3,420,841	)		—			—			(94,386	)		(202,646	)
Net realized gain – Class Y		(70,995,899	)		(67,636,681	)		(11,216,211	)		(7,136,853	)		(5,748,134	)		(2,875,291	)		(1,353,410	)		(590,564	)
Net investment income – Class Z		—			(15,891,591	)		(88,209,132	)		(155,452,351	)		—			—			(1,436,806	)		(4,109,073	)
Net realized gain – Class Z		(1,866,279,508	)		(900,665,248	)		(300,186,783	)		(249,192,931	)		(197,817,289	)		(117,566,025	)		(23,156,256	)		(18,050,611	)
Total Distributions to Shareholders		(2,682,706,755	)		(1,329,374,378	)		(529,900,732	)		(528,938,807	)		(246,242,710	)		(141,393,055	)		(34,424,447	)		(30,134,496	)
Share Transactions:
Subscriptions – Class A		387,297,277			557,145,668			235,302,578			388,100,963			25,880,527			45,008,746			17,687,288			25,343,455
Distributions reinvested – Class A		458,120,888			233,381,519			61,324,199			65,876,765			25,490,248			15,114,156			6,671,741			6,095,501
Redemptions – Class A		(1,539,008,962	)		(858,688,706	)		(328,383,569	)		(530,170,862	)		(81,566,768	)		(44,053,671	)		(33,811,493	)		(35,337,785	)
Net Increase (Decrease) – Class A		(693,590,797	)		(68,161,519	)		(31,756,792	)		(76,193,134	)		(30,195,993	)		16,069,231			(9,452,464	)		(3,898,829	)
Distributions reinvested – Class B		1,459,028			1,460,482			428,823			818,689			50,412			57,565			51,402			73,716
Redemptions – Class B		(11,842,669	)		(21,005,008	)		(6,307,820	)		(7,611,506	)		(333,713	)		(704,340	)		(493,902	)		(502,159	)
Net Increase (Decrease) – Class B		(10,383,641	)		(19,544,526	)		(5,878,997	)		(6,792,817	)		(283,301	)		(646,775	)		(442,500	)		(428,443	)
Subscriptions – Class C		69,519,166			102,078,253			20,327,395			18,300,360			2,990,564			3,731,266			1,124,408			2,209,150
Distributions reinvested – Class C		124,358,458			53,482,078			5,543,900			5,389,019			7,016,021			3,400,514			965,830			731,141
Redemptions – Class C		(204,072,123	)		(127,416,912	)		(20,718,133	)		(18,680,336	)		(7,454,664	)		(4,271,383	)		(2,579,871	)		(2,895,556	)
Net Increase (Decrease) – Class C		(10,194,499	)		28,143,419			5,153,162			5,009,043			2,551,921			2,860,397			(489,633	)		44,735
Subscriptions – Class I		82,894,450			62,857,281			106,632,159			88,004,757			—			—			—			—
Distributions reinvested – Class I		3,521,166			1,506,709			2,209,323			2,371,517			—			—			—			—
Redemptions – Class I		(79,941,110	)		(116,462,027	)		(98,916,651	)		(175,245,774	)		(1,200	)		—			(100	)		—
Net Increase (Decrease) – Class I		6,474,506			(52,098,037	)		9,924,831			(84,869,500	)		(1,200	)		—			(100	)		—
Subscriptions – Class R		—			—			3,552,904			3,579,789			—			—			—			—
Distributions reinvested – Class R		—			—			324,934			280,476			—			—			—			—
Redemptions – Class R		—			—			(3,574,734	)		(1,384,671	)		—			—			—			—
Net Increase – Class R		—			—			303,104			2,475,594			—			—			—			—

(a) Class Y shares reflect activity for the period from June 13, 2013 (commencement of operations) through December 31, 2013.

(b) Class R4 shares reflect activity for the period from June 25, 2014 (commencement of operations) through December 31, 2014.

See accompanying notes to financial statements.

	Columbia Acorn Select^SM						Columbia Thermostat Fund^SM						Columbia Acorn Emerging Markets Fund^SM						Columbia Acorn European Fund^SM
Increase (Decrease) in Net Assets	Year ended December 31,						Year ended December 31,						Year ended December 31,						Year ended December 31,
	2014			2013			2014			2013			2014			2013 (a)			2014 (b)			2013
Operations:
Net investment income (loss)	$	(3,672,062	)	$	(3,787,764	)	$	22,277,306		$	21,177,510		$	2,430,118		$	1,192,356		$	404,894		$	16,515
Net realized gain (loss) on investments, foreign currency translations, forward foreign currency exchange contracts and foreign capital gains tax		158,802,272			199,126,634			35			—			(9,229,406	)		(5,903,007	)		(2,712,928	)		290,295
Net realized gain (loss) on affiliated investments and distributions from affiliated investment company shares		(5,568,755	)		1,096,550			38,178,162			87,967,259			—			—			—			—
Net change in net unrealized appreciation (depreciation) on investments, foreign currency translations, forward foreign currency exchange contracts, options and foreign capital gains tax		(133,989,051	)		59,584,538			—			—			(14,640,892	)		30,064,776			(3,116,709	)		3,148,647
Net change in net unrealized appreciation (depreciation) on affiliated investments, affiliated options and affiliated investment company shares		854,842			7,543,133			4,982,086			(12,732,372	)		—			—			—			—
Net Increase (Decrease) in Net Assets from Operations		16,427,246			263,563,091			65,437,589			96,412,397			(21,440,180	)		25,354,125			(5,424,743	)		3,455,457
Distributions to Shareholders From:
Net investment income – Class A		—			(779,067	)		(8,397,874	)		(8,405,645	)		(1,094,797	)		(982,830	)		(84,996	)		(19,726	)
Net realized gain – Class A		(56,636,824	)		(74,628,738	)		(6,398,591	)		(24,911,710	)		—			—			(169,484	)		(17,284	)
Net investment income – Class B		—			—			(17,083	)		(26,642	)		—			—			—			—
Net realized gain – Class B		(297,506	)		(860,295	)		(18,454	)		(109,193	)		—			—			—			—
Net investment income – Class C		—			—			(4,546,957	)		(3,912,583	)		—			—			—			—
Net realized gain – Class C		(12,212,259	)		(15,474,668	)		(5,614,280	)		(20,870,877	)		—			—			(21,837	)		(1,176	)
Net investment income – Class I		—			(134,582	)		—			—			(25	)		(63	)		(17	)		(31	)
Net realized gain – Class I		(3,400,475	)		(3,544,269	)		—			—			—			—			(13	)		(8	)
Net investment income – Class R		—			—			—			—			—			—			—			—
Net realized gain – Class R		—			—			—			—			—			—			—			—
Net investment income – Class R4		—			(361	)		(496,795	)		(279,538	)		(139,747	)		(121,494	)		(1,628	)		—
Net realized gain – Class R4		(246,466	)		(146,391	)		(305,871	)		(732,207	)		—			—			—			—
Net investment income – Class R5		—			(2,205	)		(65,599	)		(17,560	)		(184,675	)		(121,239	)		(11,230	)		(5,749	)
Net realized gain – Class R5		(2,042,106	)		(2,031,137	)		(42,379	)		(45,621	)		—			—			(14,316	)		(1,913	)
Net investment income – Class Y		—			(184	)		(8,730	)		(55	)		(23	)		(27	)		—			—
Net realized gain – Class Y		(715,032	)		(819,712	)		(5,549	)		(133	)		—			—			—			—
Net investment income – Class Z		—			(2,355,271	)		(8,020,198	)		(7,145,972	)		(2,086,821	)		(1,332,785	)		(58,745	)		(15,666	)
Net realized gain – Class Z		(67,822,345	)		(101,354,640	)		(5,142,454	)		(18,354,791	)		—			—			(81,656	)		(4,486	)
Total Distributions to Shareholders		(143,373,013	)		(202,131,520	)		(39,080,814	)		(84,812,527	)		(3,506,088	)		(2,558,438	)		(443,922	)		(66,039	)
Share Transactions:
Subscriptions – Class A		23,903,410			65,389,229			109,228,793			269,301,297			111,765,309			179,677,591			30,709,434			19,592,036
Distributions reinvested – Class A		52,931,442			70,987,772			13,288,881			30,672,808			1,088,373			978,630			251,848			31,783
Redemptions – Class A		(94,474,957	)		(88,198,756	)		(196,252,756	)		(113,768,855	)		(122,334,919	)		(16,017,690	)		(25,970,474	)		(3,060,376	)
Net Increase (Decrease) – Class A		(17,640,105	)		48,178,245			(73,735,082	)		186,205,250			(9,481,237	)		164,638,531			4,990,808			16,563,443
Distributions reinvested – Class B		295,790			857,139			35,043			134,520			—			—			—			—
Redemptions – Class B		(1,910,917	)		(8,581,439	)		(1,111,595	)		(2,504,093	)		—			—			—			—
Net Increase (Decrease) – Class B		(1,615,127	)		(7,724,300	)		(1,076,552	)		(2,369,573	)		—			—			—			—
Subscriptions – Class C		3,943,141			4,254,216			71,129,998			215,445,550			16,317,984			30,902,660			5,134,061			1,250,413
Distributions reinvested – Class C		10,065,907			12,694,116			7,780,938			18,856,243			—			—			21,837			1,175
Redemptions – Class C		(15,355,912	)		(14,117,603	)		(113,101,789	)		(60,357,649	)		(5,604,206	)		(732,599	)		(974,284	)		(56,761	)
Net Increase (Decrease) – Class C		(1,346,864	)		2,830,729			(34,190,853	)		173,944,144			10,713,778			30,170,061			4,181,614			1,194,827
Subscriptions – Class I		54,126,443			41,439,706			—			—			—			—			—			—
Distributions reinvested – Class I		3,400,003			3,678,143			—			—			24			63			29			39
Redemptions – Class I		(52,140,680	)		(77,746,294	)		—			—			(4,200	)		—			(5,500	)		—
Net Increase (Decrease) – Class I		5,385,766			(32,628,445	)		—			—			(4,176	)		63			(5,471	)		39
Subscriptions – Class R		—			—			—			—			—			—			—			—
Distributions reinvested – Class R		—			—			—			—			—			—			—			—
Redemptions – Class R		—			—			—			—			—			—			—			—
Net Increase – Class R		—			—			—			—			—			—			—			—

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®						Columbia Acorn International Select^SM
Increase (Decrease) in Net Assets	Year ended December 31,						Year ended December 31,						Year ended December 31,						Year ended December 31,
	2014			2013			2014			2013			2014			2013			2014			2013
Subscriptions – Class R4		207,170,623			70,679,921			175,589,777			346,765,044			2,470,102			6,157,899			1,034,431			383,885
Distributions reinvested – Class R4		21,432,710			3,598,586			26,888,828			18,510,730			1,284,629			463,030			130,285			25,563
Redemptions – Class R4		(32,595,900	)		(5,189,707	)		(86,239,207	)		(7,666,126	)		(1,252,295	)		(397,344	)		(342,802	)		(158	)
Net Increase – Class R4		196,007,433			69,088,800			116,239,398			357,609,648			2,502,436			6,223,585			821,914			409,290
Subscriptions – Class R5		195,425,964			491,001,376			247,362,038			285,865,026			37,680,269			5,875,204			3,308,092			959,653
Distributions reinvested – Class R5		82,145,922			24,452,455			27,089,438			17,278,109			5,922,697			450,258			313,832			65,594
Redemptions – Class R5		(237,599,243	)		(47,781,358	)		(105,520,799	)		(47,512,031	)		(8,503,850	)		(553,703	)		(1,308,702	)		(79,732	)
Net Increase (Decrease) – Class R5		39,972,643			467,672,473			168,930,677			255,631,104			35,099,116			5,771,759			2,313,222			945,515
Subscriptions – Class Y		199,351,710			1,048,816,289			103,024,265			165,373,208			36,144,225			44,461,461			2,689,199			13,106,279
Distributions reinvested – Class Y		70,995,899			68,651,368			14,847,627			8,485,714			5,747,713			2,875,042			1,447,516			793,011
Redemptions – Class Y		(1,053,713,427	)		(76,908,863	)		(21,611,148	)		(60,678,159	)		(48,745,200	)		(321,655	)		(3,306,180	)		(353,711	)
Net Increase (Decrease) – Class Y		(783,365,818	)		1,040,558,794			96,260,744			113,180,763			(6,853,262	)		47,014,848			830,535			13,545,579
Subscriptions – Class Z		982,362,041			1,365,381,996			856,537,476			952,243,095			102,940,940			192,666,998			43,516,847			56,693,525
Distributions reinvested – Class Z		1,619,840,849			797,203,097			294,475,850			317,702,278			173,222,058			102,958,421			14,556,758			12,763,349
Redemptions – Class Z		(4,171,520,886	)		(3,725,592,700	)		(1,213,184,358	)		(1,257,745,052	)		(480,201,144	)		(494,803,769	)		(99,596,462	)		(122,754,727	)
Net Increase (Decrease) – Class Z		(1,569,317,996	)		(1,563,007,607	)		(62,171,032	)		12,200,321			(204,038,146	)		(199,178,350	)		(41,522,857	)		(53,297,853	)
Net Increase (Decrease) from Share Transactions		(2,824,398,169	)		(97,348,203	)		297,005,095			578,251,022			(201,218,429	)		(121,885,305	)		(47,941,883	)		(42,680,006	)
Total Increase (Decrease) in Net Assets		(5,416,395,173	)		3,827,105,287			(593,842,465	)		1,583,522,994			(403,070,116	)		200,191,730			(102,969,434	)		(24,564,920	)
Net Assets:
Beginning of period		21,350,971,198			17,523,865,911			8,327,320,600			6,743,797,606			1,800,286,403			1,600,094,673			355,889,134			380,454,054
End of period	$	15,934,576,025		$	21,350,971,198		$	7,733,478,135		$	8,327,320,600		$	1,397,216,287		$	1,800,286,403		$	252,919,700		$	355,889,134
Undistributed (Overdistributed) net investment income (loss)	$	(3,615,764	)	$	(36,590,606	)	$	(92,376,083	)	$	(119,307,605	)	$	(312,115	)	$	(286,857	)	$	(6,492,720	)	$	(12,664,698	)

(a) Class Y shares reflect activity for the period from June 13, 2013 (commencement of operations) through December 31, 2013.

(b) Class R4 shares reflect activity for the period from June 25, 2014 (commencement of operations) through December 31, 2014.

See accompanying notes to financial statements.

	Columbia Acorn Select^SM						Columbia Thermostat Fund^SM						Columbia Acorn Emerging Markets Fund^SM						Columbia Acorn European Fund^SM
Increase (Decrease) in Net Assets	Year ended December 31,						Year ended December 31,						Year ended December 31,						Year ended December 31,
	2014			2013			2014			2013			2014			2013 (a)			2014 (b)			2013
Subscriptions – Class R4		533,691			1,409,186			12,515,863			16,841,816			6,532,869			13,932,169			325,474			—
Distributions reinvested – Class R4		246,466			142,707			802,565			1,010,634			139,724			121,336			1,614			—
Redemptions – Class R4		(753,003	)		(144,546	)		(4,731,799	)		(2,678,147	)		(3,899,691	)		(1,223,601	)		(93	)		—
Net Increase – Class R4		27,154			1,407,347			8,586,629			15,174,303			2,772,902			12,829,904			326,995			—
Subscriptions – Class R5		2,302,873			10,681,076			3,265,267			1,172,670			13,884,224			13,005,283			3,323,523			1,696,121
Distributions reinvested – Class R5		2,041,638			2,032,665			106,949			62,995			184,675			121,213			25,520			7,648
Redemptions – Class R5		(3,845,123	)		(532,781	)		(815,418	)		(221,359	)		(7,252,982	)		(155,394	)		(3,409,088	)		(51,126	)
Net Increase (Decrease) – Class R5		499,388			12,180,960			2,556,798			1,014,306			6,815,917			12,971,102			(60,045	)		1,652,643
Subscriptions – Class Y		538,245			4,652,097			435,256			—			—			2,500			—			—
Distributions reinvested – Class Y		714,565			819,220			14,183			—			—			—			—			—
Redemptions – Class Y		(1,818,170	)		(557,993	)		(53,320	)		—			(200	)		—			—			—
Net Increase (Decrease) – Class Y		(565,360	)		4,913,324			396,119			—			(200	)		2,500			—			—
Subscriptions – Class Z		41,269,615			46,215,005			158,234,941			241,074,077			181,236,447			173,769,882			21,621,093			1,188,594
Distributions reinvested – Class Z		52,107,171			71,082,424			8,772,626			15,861,661			2,002,496			1,254,500			139,509			19,797
Redemptions – Class Z		(146,142,628	)		(311,970,231	)		(172,293,477	)		(180,321,598	)		(101,479,206	)		(14,317,387	)		(15,477,555	)		(502,271	)
Net Increase (Decrease) – Class Z		(52,765,842	)		(194,672,802	)		(5,285,910	)		76,614,140			81,759,737			160,706,995			6,283,047			706,120
Net Increase (Decrease) from Share Transactions		(68,020,990	)		(165,514,942	)		(102,748,851	)		450,582,570			92,576,721			381,319,156			15,716,948			20,117,072
Total Increase (Decrease) in Net Assets		(194,966,757	)		(104,083,371	)		(76,392,076	)		462,182,440			67,630,453			404,114,843			9,848,283			23,506,490
Net Assets:
Beginning of period		861,543,543			965,626,914			1,336,805,137			874,622,697			414,704,654			10,589,811			26,784,525			3,278,035
End of period	$	666,576,786		$	861,543,543		$	1,260,413,061		$	1,336,805,137		$	482,335,107		$	414,704,654		$	36,632,808		$	26,784,525
Undistributed (Overdistributed) net investment income (loss)	$	(325,960	)	$	(450,627	)	$	1,675,197		$	720,757		$	(2,486,157	)	$	(1,371,231	)	$	199,170		$	(26,208	)

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®						Columbia Acorn International Select^SM
Changes in Shares of Beneficial Interest:	Year ended December 31,						Year ended December 31,						Year ended December 31,						Year ended December 31,
	2014			2013			2014			2013			2014			2013			2014			2013
Subscriptions – Class A		11,177,523			16,772,784			5,069,057			8,721,860			786,132			1,394,169			638,165			953,061
Shares issued in reinvestment and capital gains – Class A		14,955,024			6,939,430			1,433,668			1,475,191			878,620			468,483			298,993			233,959
Less shares redeemed – Class A		(45,358,767	)		(25,665,267	)		(7,155,380	)		(11,526,833	)		(2,482,524	)		(1,355,276	)		(1,259,425	)		(1,336,213	)
Net Increase (Decrease) – Class A		(19,226,220	)		(1,953,053	)		(652,655	)		(1,329,782	)		(817,772	)		507,376			(322,267	)		(149,193	)
Shares issued in reinvestment and capital gains – Class B		53,837			48,181			10,251			18,918			1,994			1,984			2,445			2,974
Less shares redeemed – Class B		(380,244	)		(705,007	)		(141,082	)		(178,171	)		(11,206	)		(24,425	)		(19,481	)		(20,013	)
Net Increase (Decrease) – Class B		(326,407	)		(656,826	)		(130,831	)		(159,253	)		(9,212	)		(22,441	)		(17,036	)		(17,039	)
Subscriptions – Class C		2,380,665			3,426,567			455,251			425,390			106,036			128,459			43,902			88,935
Shares issued in reinvestment and capital gains – Class C		4,736,715			1,792,288			134,128			124,854			281,787			118,609			46,423			29,744
Less shares redeemed – Class C		(6,832,781	)		(4,279,659	)		(471,635	)		(436,255	)		(259,303	)		(147,379	)		(104,212	)		(115,611	)
Net Increase (Decrease) – Class C		284,599			939,196			117,744			113,989			128,520			99,689			(13,887	)		3,068
Subscriptions – Class I		2,381,215			1,885,590			2,360,586			2,038,998			—			—			—			—
Shares issued in reinvestment and capital gains – Class I		107,212			43,283			50,640			53,236			—			—			—			—
Less shares redeemed – Class I		(2,154,531	)		(3,308,111	)		(2,111,846	)		(3,848,404	)		(33	)		—			(4	)		—
Net Increase (Decrease) – Class I		333,896			(1,379,238	)		299,380			(1,756,170	)		(33	)		—			(4	)		—
Subscriptions – Class R		—			—			77,000			81,299			—			—			—			—
Shares issued in reinvestment and capital gains – Class R		—			—			7,564			6,268			—			—			—			—
Less shares redeemed – Class R		—			—			(76,075	)		(31,263	)		—			—			—			—
Net Increase – Class R		—			—			8,489			56,304			—			—			—			—
Subscriptions – Class R4		5,988,744			1,998,028			3,770,182			7,323,105			69,547			173,989			36,025			13,801
Shares issued in reinvestment and capital gains – Class R4		658,166			100,520			626,322			408,790			40,840			13,409			5,756			962
Less shares redeemed – Class R4		(900,585	)		(140,805	)		(1,864,318	)		(163,652	)		(35,802	)		(11,660	)		(13,656	)		(6	)
Net Increase – Class R4		5,746,325			1,957,743			2,532,186			7,568,243			74,585			175,738			28,125			14,757
Subscriptions – Class R5		5,371,622			13,752,426			5,374,903			6,528,156			1,039,918			167,928			113,565			35,393
Shares issued in reinvestment and capital gains – Class R5		2,508,272			680,831			636,802			385,664			188,407			13,045			13,893			2,472
Less shares redeemed – Class R5		(6,914,002	)		(1,319,787	)		(2,352,664	)		(1,038,451	)		(237,562	)		(14,967	)		(46,841	)		(2,971	)
Net Increase (Decrease) – Class R5		965,892			13,113,470			3,659,041			5,875,369			990,763			166,006			80,617			34,894
Subscriptions – Class Y		5,405,607			30,418,210			2,180,767			3,692,396			989,024			1,250,341			95,911			470,106
Shares issued in reinvestment and capital gains – Class Y		2,114,206			1,921,971			346,391			187,806			182,296			83,147			63,827			29,869
Less shares redeemed – Class Y		(28,273,237	)		(2,138,695	)		(474,107	)		(1,329,828	)		(1,378,135	)		(8,744	)		(122,660	)		(12,731	)
Net Increase (Decrease) – Class Y		(20,753,424	)		30,201,486			2,053,051			2,550,374			(206,815	)		1,324,744			37,078			487,244
Subscriptions – Class Z		27,275,542			39,991,834			18,575,064			21,587,060			2,943,870			5,769,866			1,572,550			2,139,566
Shares issued in reinvestment and capital gains – Class Z		50,258,476			22,754,352			6,885,453			7,096,454			5,614,121			3,036,499			645,241			484,755
Less shares redeemed – Class Z		(116,645,260	)		(107,868,830	)		(26,436,650	)		(28,414,984	)		(13,762,562	)		(15,174,383	)		(3,750,710	)		(4,625,116	)
Net Increase (Decrease) – Class Z		(39,111,242	)		(45,122,644	)		(976,133	)		268,530			(5,204,571	)		(6,368,018	)		(1,532,919	)		(2,000,795	)
Net Increase (Decrease) in Shares of Beneficial Interest		(72,086,581	)		(2,899,866	)		6,910,272			13,187,604			(5,044,535	)		(4,116,906	)		(1,740,293	)		(1,627,064	)

(a) Class Y shares reflect activity for the period from June 13, 2013 (commencement of operations) through December 31, 2013.

(b) Class R4 shares reflect activity for the period from June 25, 2014 (commencement of operations) through December 31, 2014.

See accompanying notes to financial statements.

100

	Columbia Acorn Select^SM						Columbia Thermostat Fund^SM						Columbia Acorn Emerging Markets Fund^SM						Columbia Acorn European Fund^SM
Changes in Shares of Beneficial Interest:	Year ended December 31,						Year ended December 31,						Year ended December 31,						Year ended December 31,
	2014			2013			2014			2013			2014			2013 (a)			2014 (b)			2013
Subscriptions – Class A		999,673			2,409,551			7,304,585			17,981,201			8,480,721			14,185,095			1,976,901			1,389,036
Shares issued in reinvestment and capital gains – Class A		2,437,585			2,880,725			893,241			2,106,160			85,241			75,048			16,205			2,142
Less shares redeemed – Class A		(3,902,541	)		(3,250,484	)		(13,113,073	)		(7,527,423	)		(9,160,435	)		(1,269,880	)		(1,738,341	)		(212,961	)
Net Increase (Decrease) – Class A		(465,283	)		2,039,792			(4,915,247	)		12,559,938			(594,473	)		12,990,263			254,765			1,178,217
Shares issued in reinvestment and capital gains – Class B		15,514			38,348			2,338			9,173			—			—			—			—
Less shares redeemed – Class B		(88,114	)		(346,271	)		(74,245	)		(166,345	)		—			—			—			—
Net Increase (Decrease) – Class B		(72,600	)		(307,923	)		(71,907	)		(157,172	)		—			—			—			—
Subscriptions – Class C		200,609			184,785			4,743,432			14,371,325			1,237,012			2,457,588			335,241			86,894
Shares issued in reinvestment and capital gains – Class C		546,759			583,469			519,687			1,285,939			—			—			1,380			80
Less shares redeemed – Class C		(740,621	)		(577,080	)		(7,542,466	)		(3,977,289	)		(430,442	)		(58,728	)		(66,938	)		(4,470	)
Net Increase (Decrease) – Class C		6,747			191,174			(2,279,347	)		11,679,975			806,570			2,398,860			269,683			82,504
Subscriptions – Class I		2,177,235			1,503,059			—			—			—			—			—			—
Shares issued in reinvestment and capital gains – Class I		143,898			141,436			—			—			2			5			2			3
Less shares redeemed – Class I		(1,994,457	)		(2,658,803	)		—			—			(313	)		—			(346	)		—
Net Increase (Decrease) – Class I		326,676			(1,014,308	)		—			—			(311	)		5			(344	)		3
Subscriptions – Class R		—			—			—			—			—			—			—			—
Shares issued in reinvestment and capital gains – Class R		—			—			—			—			—			—			—			—
Less shares redeemed – Class R		—			—			—			—			—			—			—			—
Net Increase – Class R		—			—			—			—			—			—			—			—
Subscriptions – Class R4		20,220			49,613			838,999			1,120,984			479,110			1,090,642			20,884			—
Shares issued in reinvestment and capital gains – Class R4		10,486			5,524			54,396			69,981			10,917			9,227			111			—
Less shares redeemed – Class R4		(29,113	)		(4,872	)		(318,210	)		(179,054	)		(291,550	)		(93,939	)		(6	)		—
Net Increase – Class R4		1,593			50,265			575,185			1,011,911			198,477			1,005,930			20,989			—
Subscriptions – Class R5		87,557			381,566			219,576			77,722			1,041,821			1,013,748			208,383			122,328
Shares issued in reinvestment and capital gains – Class R5		87,341			78,762			7,242			4,359			14,425			9,225			1,646			511
Less shares redeemed – Class R5		(146,321	)		(19,370	)		(54,794	)		(14,647	)		(536,066	)		(12,077	)		(216,692	)		(3,541	)
Net Increase (Decrease) – Class R5		28,577			440,958			172,024			67,434			520,180			1,010,896			(6,663	)		119,298
Subscriptions – Class Y		20,305			164,585			29,656			—			—			205			—			—
Shares issued in reinvestment and capital gains – Class Y		30,390			31,675			962			—			—			—			—			—
Less shares redeemed – Class Y		(69,067	)		(18,601	)		(3,571	)		—			(15	)		—			—			—
Net Increase (Decrease) – Class Y		(18,372	)		177,659			27,047			—			(15	)		205			—			—
Subscriptions – Class Z		1,616,671			1,677,809			10,700,096			16,316,167			13,528,786			13,732,748			1,375,486			85,515
Shares issued in reinvestment and capital gains – Class Z		2,273,717			2,759,330			597,366			1,102,717			157,433			96,057			9,056			1,334
Less shares redeemed – Class Z		(5,760,728	)		(11,254,870	)		(11,671,258	)		(12,064,146	)		(7,722,797	)		(1,131,598	)		(1,072,883	)		(37,709	)
Net Increase (Decrease) – Class Z		(1,870,340	)		(6,817,731	)		(373,796	)		5,354,738			5,963,422			12,697,207			311,659			49,140
Net Increase (Decrease) in Shares of Beneficial Interest		(2,063,002	)		(5,240,114	)		(6,866,041	)		30,516,824			6,893,850			30,103,366			850,089			1,429,162

See accompanying notes to financial statements.

101

Columbia Acorn Family of Funds

Financial Highlights

The following tables are intended to help you understand the Fund's financial performance. Certain information reflects financial results for a single share of a class held for the periods shown. Per share net investment income (loss) amounts are calculated based on average shares outstanding during the period. Total return assumes reinvestment of all dividends and distributions, if any. Total return does not reflect payment of sales charges, if any. Total return and portfolio turnover are not annualized for periods of less than one year. The portfolio turnover rate is calculated without regard to purchase and sales transactions of short-term instruments and certain derivatives, if any. If such transactions were included, the Fund's portfolio turnover rate may be higher.

Columbia Acorn® Fund

			Income from Investment Operations									Less Distributions to Shareholders
(Selected data for a share outstanding throughout each period)	Net Asset Value, Beginning of Period		Net investment income (loss)			Net realized and unrealized gain (loss)			Total from investment operations			Net investment income			Net realized gains			Total Distributions to Shareholders			Increase from regulatory settlements
Class A
Year Ended December 31, 2014	$	35.78		(0.08	)		0.21			0.13			—			(5.61	)		(5.61	)		—
Year Ended December 31, 2013	$	29.36		(0.06	)		8.84			8.78			(0.04	)		(2.32	)		(2.36	)		—
Year Ended December 31, 2012	$	26.63		0.08			4.53			4.61			(0.06	)		(1.82	)		(1.88	)		—
Year Ended December 31, 2011	$	29.24		(0.10	)		(1.30	)		(1.40	)		(0.02	)		(1.19	)		(1.21	)		—
Year Ended December 31, 2010	$	23.98		(0.06	)		6.18			6.12			(0.02	)		(0.84	)		(0.86	)		0.00	(c)
Class B
Year Ended December 31, 2014	$	32.25		(0.29	)		0.18			(0.11	)		—			(5.61	)		(5.61	)		—
Year Ended December 31, 2013	$	26.80		(0.25	)		8.02			7.77			—			(2.32	)		(2.32	)		—
Year Ended December 31, 2012	$	24.53		(0.11	)		4.20			4.09			—			(1.82	)		(1.82	)		—
Year Ended December 31, 2011	$	27.14		(0.27	)		(1.15	)		(1.42	)		—			(1.19	)		(1.19	)		—
Year Ended December 31, 2010	$	22.43		(0.21	)		5.76			5.55			—			(0.84	)		(0.84	)		0.00	(c)
Class C
Year Ended December 31, 2014	$	31.64		(0.28	)		0.17			(0.11	)		—			(5.61	)		(5.61	)		—
Year Ended December 31, 2013	$	26.34		(0.26	)		7.88			7.62			—			(2.32	)		(2.32	)		—
Year Ended December 31, 2012	$	24.18		(0.12	)		4.10			3.98			—			(1.82	)		(1.82	)		—
Year Ended December 31, 2011	$	26.85		(0.29	)		(1.19	)		(1.48	)		—			(1.19	)		(1.19	)		—
Year Ended December 31, 2010	$	22.23		(0.24	)		5.70			5.46			—			(0.84	)		(0.84	)		0.00	(c)
Class I
Year Ended December 31, 2014	$	37.37		0.05			0.22			0.27			—			(5.61	)		(5.61	)		—
Year Ended December 31, 2013	$	30.47		0.06			9.20			9.26			(0.04	)		(2.32	)		(2.36	)		—
Year Ended December 31, 2012	$	27.57		0.26			4.62			4.88			(0.16	)		(1.82	)		(1.98	)		—
Year Ended December 31, 2011	$	30.19		0.01			(1.35	)		(1.34	)		(0.09	)		(1.19	)		(1.28	)		—
Year Ended December 31, 2010 (d)	$	26.80		(0.01	)		4.26			4.25			(0.02	)		(0.84	)		(0.86	)		—
Class R4
Year Ended December 31, 2014	$	37.88		0.02			0.22			0.24			—			(5.61	)		(5.61	)		—
Year Ended December 31, 2013	$	30.90		0.06			9.29			9.35			(0.05	)		(2.32	)		(2.37	)		—
Year Ended December 31, 2012 (f)	$	30.59		0.05			1.84			1.89			(0.12	)		(1.46	)		(1.58	)		—
Class R5
Year Ended December 31, 2014	$	37.89		0.04			0.23			0.27			—			(5.61	)		(5.61	)		—
Year Ended December 31, 2013	$	30.88		0.07			9.30			9.37			(0.04	)		(2.32	)		(2.36	)		—
Year Ended December 31, 2012 (g)	$	30.59		0.06			1.83			1.89			(0.14	)		(1.46	)		(1.60	)		—
Class Y
Year Ended December 31, 2014	$	37.93		0.05			0.24			0.29			—			(5.61	)		(5.61	)		—
Year Ended December 31, 2013	$	30.90		0.09			9.31			9.40			(0.05	)		(2.32	)		(2.37	)		—
Year Ended December 31, 2012 (h)	$	30.62		0.09			1.80			1.89			(0.15	)		(1.46	)		(1.61	)		—
Class Z
Year Ended December 31, 2014	$	37.32		0.02			0.22			0.24			—			(5.61	)		(5.61	)		—
Year Ended December 31, 2013	$	30.45		0.04			9.19			9.23			(0.04	)		(2.32	)		(2.36	)		—
Year Ended December 31, 2012	$	27.56		0.17			4.69			4.86			(0.15	)		(1.82	)		(1.97	)		—
Year Ended December 31, 2011	$	30.19		(0.01	)		(1.34	)		(1.35	)		(0.09	)		(1.19	)		(1.28	)		—
Year Ended December 31, 2010	$	24.68		0.02			6.37			6.39			(0.04	)		(0.84	)		(0.88	)		0.00	(c)

Notes to Financial Highlights

(a) In addition to the fees and expenses that the Fund bears directly, the Fund indirectly bears a pro rata share of the fees and expenses of any other funds in which it invests, if any. Such indirect expenses are not included in the Fund's reported expense ratios.

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

(d) Class I shares commenced operations on September 27, 2010. Per share data and total return reflect activity from that date.

(e) Annualized.

(f) Class R4 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(g) Class R5 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(h) Class Y shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

See accompanying notes to financial statements.

102

						Ratio to Average Net Assets									Supplemental Data
(Selected data for a share outstanding throughout each period)	Net Asset Value, End of Period		Total Return			Total gross expenses (a)			Total net expenses (a)			Net investment income (loss)			Portfolio turnover rate			Net assets, end of period (000s)
Class A
Year Ended December 31, 2014	$	30.30		0.55	%		1.08	%		1.08	%		(0.22	)%		17	%	$	2,694,610
Year Ended December 31, 2013	$	35.78		30.53	%		1.07	%		1.07	%		(0.17	)%		18	%	$	3,869,734
Year Ended December 31, 2012	$	29.36		17.62	%		1.06	%		1.06	%(b)		0.27	%		16	%	$	3,233,494
Year Ended December 31, 2011	$	26.63		(4.91	)%		1.06	%		1.06	%(b)		(0.33	)%		18	%	$	3,246,833
Year Ended December 31, 2010	$	29.24		25.61	%		1.07	%		1.07	%(b)		(0.22	)%		28	%	$	3,639,788
Class B
Year Ended December 31, 2014	$	26.53		(0.16	)%		1.75	%		1.75	%		(0.91	)%		17	%	$	7,201
Year Ended December 31, 2013	$	32.25		29.63	%		1.73	%		1.73	%		(0.84	)%		18	%	$	19,278
Year Ended December 31, 2012	$	26.80		16.98	%		1.65	%		1.64	%(b)		(0.42	)%		16	%	$	33,623
Year Ended December 31, 2011	$	24.53		(5.34	)%		1.67	%		1.67	%(b)		(0.98	)%		18	%	$	67,153
Year Ended December 31, 2010	$	27.14		24.81	%		1.69	%		1.69	%(b)		(0.88	)%		28	%	$	287,650
Class C
Year Ended December 31, 2014	$	25.92		(0.16	)%		1.77	%		1.77	%		(0.92	)%		17	%	$	776,370
Year Ended December 31, 2013	$	31.64		29.58	%		1.78	%		1.78	%		(0.88	)%		18	%	$	938,644
Year Ended December 31, 2012	$	26.34		16.77	%		1.80	%		1.80	%(b)		(0.46	)%		16	%	$	756,709
Year Ended December 31, 2011	$	24.18		(5.63	)%		1.82	%		1.82	%(b)		(1.10	)%		18	%	$	721,446
Year Ended December 31, 2010	$	26.85		24.63	%		1.85	%		1.85	%(b)		(1.00	)%		28	%	$	829,181
Class I
Year Ended December 31, 2014	$	32.03		0.91	%		0.70	%		0.70	%		0.14	%		17	%	$	28,164
Year Ended December 31, 2013	$	37.37		30.99	%		0.70	%		0.70	%		0.16	%		18	%	$	20,383
Year Ended December 31, 2012	$	30.47		18.02	%		0.72	%		0.72	%(b)		0.86	%		16	%	$	58,652
Year Ended December 31, 2011	$	27.57		(4.57	)%		0.72	%		0.72	%(b)		0.02	%		18	%	$	16,397
Year Ended December 31, 2010 (d)	$	30.19		15.94	%		0.71	%(e)		0.71	%(b)(e)		(0.13	)%(e)		28	%	$	11,627
Class R4
Year Ended December 31, 2014	$	32.51		0.81	%		0.84	%		0.84	%		0.05	%		17	%	$	250,457
Year Ended December 31, 2013	$	37.88		30.85	%		0.80	%		0.80	%		0.16	%		18	%	$	74,188
Year Ended December 31, 2012 (f)	$	30.90		6.31	%		0.87	%(e)		0.86	%(b)(e)		1.24	%(e)		16	%	$	17
Class R5
Year Ended December 31, 2014	$	32.55		0.89	%		0.76	%		0.76	%		0.10	%		17	%	$	458,223
Year Ended December 31, 2013	$	37.89		30.94	%		0.75	%		0.75	%		0.20	%		18	%	$	496,906
Year Ended December 31, 2012 (g)	$	30.88		6.33	%		0.82	%(e)		0.81	%(b)(e)		1.29	%(e)		16	%	$	3
Class Y
Year Ended December 31, 2014	$	32.61		0.94	%		0.70	%		0.70	%		0.13	%		17	%	$	378,780
Year Ended December 31, 2013	$	37.93		30.99	%		0.70	%		0.70	%		0.26	%		18	%	$	1,227,891
Year Ended December 31, 2012 (h)	$	30.90		6.34	%		0.75	%(e)		0.75	%(b)(e)		2.21	%(e)		16	%	$	67,012
Class Z
Year Ended December 31, 2014	$	31.95		0.82	%		0.79	%		0.79	%		0.07	%		17	%	$	11,340,770
Year Ended December 31, 2013	$	37.32		30.90	%		0.78	%		0.78	%		0.12	%		18	%	$	14,703,948
Year Ended December 31, 2012	$	30.45		17.93	%		0.78	%		0.78	%(b)		0.57	%		16	%	$	13,374,355
Year Ended December 31, 2011	$	27.56		(4.61	)%		0.76	%		0.76	%(b)		(0.03	)%		18	%	$	12,284,748
Year Ended December 31, 2010	$	30.19		26.00	%		0.76	%		0.76	%(b)		0.09	%		28	%	$	13,330,466

See accompanying notes to financial statements.

103

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn International®

			Income from Investment Operations												Less Distributions to Shareholders
(Selected data for a share outstanding throughout each period)	Net Asset Value, Beginning of Period		Net investment income (loss)			Net realized and unrealized gain (loss)			Reimbursement from affiliate			Total from investment operations			Net investment income			Net realized gains			Total Distributions to Shareholders			Redemption fees added to paid in capital
Class A
Year Ended December 31, 2014	$	46.63		0.42			(2.51	)		—			(2.09	)		(0.55	)		(2.31	)		(2.86	)		—
Year Ended December 31, 2013	$	40.79		0.45			8.37			—			8.82			(1.05	)		(1.93	)		(2.98	)		—
Year Ended December 31, 2012	$	34.15		0.47			6.75			—			7.22			(0.58	)		—			(0.58	)		—
Year Ended December 31, 2011	$	40.87		0.32			(6.02	)		0.00	(c)		(5.70	)		(1.02	)		—			(1.02	)		—
Year Ended December 31, 2010	$	34.13		0.22			7.21			—			7.43			(0.69	)		—			(0.69	)		0.00	(c)
Class B
Year Ended December 31, 2014	$	45.24		0.07			(2.42	)		—			(2.35	)		(0.20	)		(2.31	)		(2.51	)		—
Year Ended December 31, 2013	$	39.67		0.12			8.10			—			8.22			(0.72	)		(1.93	)		(2.65	)		—
Year Ended December 31, 2012	$	33.17		0.19			6.55			—			6.74			(0.24	)		—			(0.24	)		—
Year Ended December 31, 2011	$	39.96		0.06			(5.85	)		0.00	(c)		(5.79	)		(1.00	)		—			(1.00	)		—
Year Ended December 31, 2010	$	33.22		0.03			7.02			—			7.05			(0.31	)		—			(0.31	)		0.00	(c)
Class C
Year Ended December 31, 2014	$	45.04		0.07			(2.40	)		—			(2.33	)		(0.20	)		(2.31	)		(2.51	)		—
Year Ended December 31, 2013	$	39.50		0.10			8.08			—			8.18			(0.71	)		(1.93	)		(2.64	)		—
Year Ended December 31, 2012	$	33.03		0.18			6.52			—			6.70			(0.23	)		—			(0.23	)		—
Year Ended December 31, 2011	$	39.79		0.04			(5.86	)		0.00	(c)		(5.82	)		(0.94	)		—			(0.94	)		—
Year Ended December 31, 2010	$	33.08		(0.05	)		7.03			—			6.98			(0.27	)		—			(0.27	)		0.00	(c)
Class I
Year Ended December 31, 2014	$	46.71		0.59			(2.51	)		—			(1.92	)		(0.72	)		(2.31	)		(3.03	)		—
Year Ended December 31, 2013	$	40.86		0.66			8.34			—			9.00			(1.22	)		(1.93	)		(3.15	)		—
Year Ended December 31, 2012	$	34.33		0.57			6.83			—			7.40			(0.87	)		—			(0.87	)		—
Year Ended December 31, 2011	$	40.92		0.37			(5.94	)		0.00	(c)		(5.57	)		(1.02	)		—			(1.02	)		—
Year Ended December 31, 2010 (f)	$	37.69		0.08			3.49			—			3.57			(0.34	)		—			(0.34	)		0.00	(c)
Class R
Year Ended December 31, 2014	$	46.60		0.24			(2.50	)		—			(2.26	)		(0.36	)		(2.31	)		(2.67	)		—
Year Ended December 31, 2013	$	40.79		0.26			8.36			—			8.62			(0.88	)		(1.93	)		(2.81	)		—
Year Ended December 31, 2012	$	34.11		0.21			6.89			—			7.10			(0.42	)		—			(0.42	)		—
Year Ended December 31, 2011 (h)	$	40.11		(0.00	)(c)		(6.00	)		0.00	(c)		(6.00	)		—			—			—			—
Class R4
Year Ended December 31, 2014	$	46.99		0.50			(2.52	)		—			(2.02	)		(0.64	)		(2.31	)		(2.95	)		—
Year Ended December 31, 2013	$	41.08		0.34			8.67			—			9.01			(1.17	)		(1.93	)		(3.10	)		—
Year Ended December 31, 2012 (i)	$	39.86		(0.00	)(c)		1.81			—			1.81			(0.59	)		—			(0.59	)		—
Class R5
Year Ended December 31, 2014	$	46.66		0.57			(2.51	)		—			(1.94	)		(0.70	)		(2.31	)		(3.01	)		—
Year Ended December 31, 2013	$	40.81		0.63			8.34			—			8.97			(1.19	)		(1.93	)		(3.12	)		—
Year Ended December 31, 2012	$	34.31		0.75			6.62			—			7.37			(0.87	)		—			(0.87	)		—
Year Ended December 31, 2011 (j)	$	40.24		0.09			(6.02	)		0.00	(c)		(5.93	)		—			—			—			—
Class Y
Year Ended December 31, 2014	$	46.99		0.58			(2.52	)		—			(1.94	)		(0.72	)		(2.31	)		(3.03	)		—
Year Ended December 31, 2013	$	41.08		0.57			8.48			—			9.05			(1.21	)		(1.93	)		(3.14	)		—
Year Ended December 31, 2012 (k)	$	39.90		0.04			1.78			—			1.82			(0.64	)		—			(0.64	)		—
Class Z
Year Ended December 31, 2014	$	46.68		0.56			(2.51	)		—			(1.95	)		(0.69	)		(2.31	)		(3.00	)		—
Year Ended December 31, 2013	$	40.84		0.58			8.38			—			8.96			(1.19	)		(1.93	)		(3.12	)		—
Year Ended December 31, 2012	$	34.31		0.59			6.78			—			7.37			(0.84	)		—			(0.84	)		—
Year Ended December 31, 2011	$	40.92		0.48			(6.07	)		0.00	(c)		(5.59	)		(1.02	)		—			(1.02	)		—
Year Ended December 31, 2010	$	34.26		0.35			7.23			—			7.58			(0.92	)		—			(0.92	)		0.00	(c)

Notes to Financial Highlights

(b) Had the Investment Manager and/or its affiliates not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

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

(e) During the year ended December 31, 2011, Columbia Management reimbursed the Fund for a loss on a trading error. Had the Fund not received this reimbursement, total return would have been lower by less than 0.01%.

(f) Class I shares commenced operations on September 27, 2010. Per share data and total return reflect activity from that date.

(g) Annualized.

(h) Class R shares commenced operations on August 2, 2011. Per share data and total return reflect activity from that date.

(i) Class R4 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(j) Class R5 shares commenced operations on August 2, 2011. Per share data and total return reflect activity from that date.

(k) Class Y shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

See accompanying notes to financial statements.

104

									Ratio to Average Net Assets									Supplemental Data
(Selected data for a share outstanding throughout each period)	Increase from regulatory settlements			Net Asset Value, End of Period		Total Return			Total gross expenses (a)			Total net expenses (a)			Net investment income (loss)			Portfolio turnover rate			Net assets, end of period (000s)
Class A
Year Ended December 31, 2014		—		$	41.68		(4.58	)%(b)		1.26	%		1.22	%		0.91	%		28	%	$	946,553
Year Ended December 31, 2013		—		$	46.63		22.00	%(b)		1.27	%		1.23	%		1.02	%		45	%	$	1,089,263
Year Ended December 31, 2012		0.00	(c)	$	40.79		21.21	%(b)		1.28	%		1.24	%(d)		1.22	%		33	%	$	1,007,236
Year Ended December 31, 2011		0.00	(c)	$	34.15		(14.37	)%(b)(e)		1.32	%		1.30	%(d)		0.84	%		32	%	$	918,112
Year Ended December 31, 2010		0.00	(c)	$	40.87		22.23	%		1.35	%		1.35	%(d)		0.62	%		25	%	$	810,603
Class B
Year Ended December 31, 2014		—		$	40.38		(5.29	)%(b)		2.00	%		1.97	%		0.16	%		28	%	$	6,516
Year Ended December 31, 2013		—		$	45.24		21.08	%(b)		2.00	%		1.97	%		0.27	%		45	%	$	13,218
Year Ended December 31, 2012		0.00	(c)	$	39.67		20.33	%(b)		2.00	%		1.97	%(d)		0.51	%		33	%	$	17,910
Year Ended December 31, 2011		0.00	(c)	$	33.17		(14.92	)%(b)(e)		1.98	%		1.96	%(d)		0.15	%		32	%	$	24,510
Year Ended December 31, 2010		0.00	(c)	$	39.96		21.49	%		1.96	%		1.96	%(d)		0.08	%		25	%	$	29,368
Class C
Year Ended December 31, 2014		—		$	40.20		(5.27	)%(b)		1.99	%		1.97	%		0.16	%		28	%	$	103,691
Year Ended December 31, 2013		—		$	45.04		21.07	%(b)		2.01	%		1.99	%		0.23	%		45	%	$	110,875
Year Ended December 31, 2012		0.00	(c)	$	39.50		20.31	%(b)		2.02	%		2.00	%(d)		0.48	%		33	%	$	92,748
Year Ended December 31, 2011		0.00	(c)	$	33.03		(15.02	)%(b)(e)		2.07	%		2.06	%(d)		0.10	%		32	%	$	97,328
Year Ended December 31, 2010		0.00	(c)	$	39.79		21.34	%		2.11	%		2.11	%(d)		(0.13	)%		25	%	$	110,931
Class I
Year Ended December 31, 2014		—		$	41.76		(4.20	)%		0.85	%		0.85	%		1.26	%		28	%	$	38,804
Year Ended December 31, 2013		—		$	46.71		22.43	%		0.85	%		0.85	%		1.49	%		45	%	$	29,418
Year Ended December 31, 2012		0.00	(c)	$	40.86		21.69	%		0.88	%		0.88	%(d)		1.48	%		33	%	$	97,484
Year Ended December 31, 2011		0.00	(c)	$	34.33		(14.02	)%(e)		0.91	%		0.91	%(d)		0.99	%		32	%	$	50,335
Year Ended December 31, 2010 (f)		—		$	40.92		9.50	%		0.94	%(g)		0.94	%(d)(g)		0.77	%(g)		25	%	$	66,581
Class R
Year Ended December 31, 2014		—		$	41.67		(4.95	)%		1.63	%		1.63	%		0.52	%		28	%	$	5,560
Year Ended December 31, 2013		—		$	46.60		21.50	%		1.63	%		1.63	%		0.58	%		45	%	$	5,822
Year Ended December 31, 2012		0.00	(c)	$	40.79		20.83	%		1.52	%		1.51	%(d)		0.54	%		33	%	$	2,799
Year Ended December 31, 2011 (h)		0.00	(c)	$	34.11		(14.96	)%		1.59	%(g)		1.59	%(d)(g)		(0.02	)%(g)		32	%	$	2,130
Class R4
Year Ended December 31, 2014		—		$	42.02		(4.39	)%		1.04	%		1.04	%		1.07	%		28	%	$	424,425
Year Ended December 31, 2013		—		$	46.99		22.32	%		1.03	%		1.03	%		0.73	%		45	%	$	355,616
Year Ended December 31, 2012 (i)		—		$	41.08		4.57	%		1.03	%(g)		1.02	%(d)(g)		(0.02	)%(g)		33	%	$	15
Class R5
Year Ended December 31, 2014		—		$	41.71		(4.25	)%		0.90	%		0.90	%		1.23	%		28	%	$	397,882
Year Ended December 31, 2013		—		$	46.66		22.38	%		0.91	%		0.91	%		1.40	%		45	%	$	274,415
Year Ended December 31, 2012		0.00	(c)	$	40.81		21.61	%		0.89	%		0.89	%(d)		1.99	%		33	%	$	242
Year Ended December 31, 2011 (j)		0.00	(c)	$	34.31		(14.74	)%		0.91	%(g)		0.91	%(d)(g)		0.65	%(g)		32	%	$	2,038
Class Y
Year Ended December 31, 2014		—		$	42.02		(4.21	)%		0.85	%		0.85	%		1.25	%		28	%	$	225,012
Year Ended December 31, 2013		—		$	46.99		22.44	%		0.86	%		0.86	%		1.26	%		45	%	$	155,140
Year Ended December 31, 2012 (k)		—		$	41.08		4.59	%		0.91	%(g)		0.90	%(d)(g)		0.75	%(g)		33	%	$	30,856
Class Z
Year Ended December 31, 2014		—		$	41.73		(4.28	)%		0.93	%		0.93	%		1.20	%		28	%	$	5,585,035
Year Ended December 31, 2013		—		$	46.68		22.33	%		0.93	%		0.93	%		1.30	%		45	%	$	6,293,552
Year Ended December 31, 2012		0.00	(c)	$	40.84		21.60	%		0.93	%		0.93	%(d)		1.53	%		33	%	$	5,494,506
Year Ended December 31, 2011		0.00	(c)	$	34.31		(14.06	)%(e)		0.95	%		0.95	%(d)		1.24	%		32	%	$	4,322,500
Year Ended December 31, 2010		0.00	(c)	$	40.92		22.70	%		0.97	%		0.97	%(d)		0.99	%		25	%	$	5,107,580

See accompanying notes to financial statements.

105

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn USA®

			Income from Investment Operations									Less Distributions to Shareholders
(Selected data for a share outstanding throughout each period)	Net Asset Value, Beginning of Period		Net investment income (loss)			Net realized and unrealized gain (loss)			Total from investment operations			Net investment income			Net realized gains			Total Distributions to Shareholders
Class A
Year Ended December 31, 2014	$	34.15		(0.20	)		1.22			1.02			—			(6.04	)		(6.04	)
Year Ended December 31, 2013	$	28.21		(0.15	)		9.09			8.94			—			(3.00	)		(3.00	)
Year Ended December 31, 2012	$	25.94		0.02			4.73			4.75			(0.11	)		(2.37	)		(2.48	)
Year Ended December 31, 2011	$	27.54		(0.22	)		(1.21	)		(1.43	)		—			(0.17	)		(0.17	)
Year Ended December 31, 2010	$	22.43		(0.15	)		5.26			5.11			—			—			—
Class B
Year Ended December 31, 2014	$	30.70		(0.46	)		1.07			0.61			—			(6.04	)		(6.04	)
Year Ended December 31, 2013	$	25.81		(0.39	)		8.28			7.89			—			(3.00	)		(3.00	)
Year Ended December 31, 2012	$	23.98		(0.19	)		4.39			4.20			—			(2.37	)		(2.37	)
Year Ended December 31, 2011	$	25.60		(0.37	)		(1.08	)		(1.45	)		—			(0.17	)		(0.17	)
Year Ended December 31, 2010	$	20.99		(0.30	)		4.91			4.61			—			—			—
Class C
Year Ended December 31, 2014	$	30.33		(0.37	)		1.06			0.69			—			(6.04	)		(6.04	)
Year Ended December 31, 2013	$	25.49		(0.33	)		8.17			7.84			—			(3.00	)		(3.00	)
Year Ended December 31, 2012	$	23.72		(0.16	)		4.30			4.14			—			(2.37	)		(2.37	)
Year Ended December 31, 2011	$	25.39		(0.39	)		(1.11	)		(1.50	)		—			(0.17	)		(0.17	)
Year Ended December 31, 2010	$	20.84		(0.31	)		4.86			4.55			—			—			—
Class I
Year Ended December 31, 2014	$	35.99		(0.06	)		1.30			1.24			—			(6.04	)		(6.04	)
Year Ended December 31, 2013	$	29.47		(0.02	)		9.54			9.52			—			(3.00	)		(3.00	)
Year Ended December 31, 2012	$	27.00		(0.10	)		5.16			5.06			(0.22	)		(2.37	)		(2.59	)
Year Ended December 31, 2011	$	28.56		(0.14	)		(1.25	)		(1.39	)		—			(0.17	)		(0.17	)
Year Ended December 31, 2010 (d)	$	24.24		(0.03	)		4.35			4.32			—			—			—
Class R4
Year Ended December 31, 2014	$	36.55		(0.11	)		1.30			1.19			—			(6.04	)		(6.04	)
Year Ended December 31, 2013	$	29.92		0.00	(f)		9.63			9.63			—			(3.00	)		(3.00	)
Year Ended December 31, 2012 (g)	$	30.06		0.06			2.28			2.34			(0.16	)		(2.32	)		(2.48	)
Class R5
Year Ended December 31, 2014	$	36.53		(0.06	)		1.28			1.22			—			(6.04	)		(6.04	)
Year Ended December 31, 2013	$	29.90		0.02			9.61			9.63			—			(3.00	)		(3.00	)
Year Ended December 31, 2012 (h)	$	30.06		0.07			2.27			2.34			(0.18	)		(2.32	)		(2.50	)
Class Y
Year Ended December 31, 2014	$	36.59		(0.07	)		1.32			1.25			—			(6.04	)		(6.04	)
Year Ended December 31, 2013	$	29.93		0.02			9.64			9.66			—			(3.00	)		(3.00	)
Year Ended December 31, 2012 (i)	$	30.10		0.07			2.27			2.34			(0.19	)		(2.32	)		(2.51	)
Class Z
Year Ended December 31, 2014	$	35.90		(0.12	)		1.29			1.17			—			(6.04	)		(6.04	)
Year Ended December 31, 2013	$	29.45		(0.07	)		9.52			9.45			—			(3.00	)		(3.00	)
Year Ended December 31, 2012	$	26.98		0.11			4.92			5.03			(0.19	)		(2.37	)		(2.56	)
Year Ended December 31, 2011	$	28.56		(0.14	)		(1.27	)		(1.41	)		—			(0.17	)		(0.17	)
Year Ended December 31, 2010	$	23.19		(0.08	)		5.45			5.37			—			—			—

Notes to Financial Highlights

(b) Ratios include line of credit interest expense which is less than 0.01%.

(d) Class I shares commenced operations on September 27, 2010. Per share data and total return reflect activity from that date.

(e) Annualized.

(f) Rounds to zero.

(g) Class R4 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(h) Class R5 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(i) Class Y shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

See accompanying notes to financial statements.

106

						Ratio to Average Net Assets									Supplemental Data
(Selected data for a share outstanding throughout each period)	Net Asset Value, End of Period		Total Return			Total gross expenses (a)			Total net expenses (a)			Net investment income (loss)			Portfolio turnover rate			Net assets, end of period (000s)
Class A
Year Ended December 31, 2014	$	29.13		3.35	%		1.33	%		1.33	%		(0.60	)%		12	%	$	148,089
Year Ended December 31, 2013	$	34.15		32.34	%		1.32	%		1.32	%		(0.46	)%		17	%	$	201,559
Year Ended December 31, 2012	$	28.21		18.67	%		1.32	%(b)		1.32	%(b)(c)		0.08	%		14	%	$	152,164
Year Ended December 31, 2011	$	25.94		(5.21	)%		1.30	%		1.30	%(c)		(0.78	)%		20	%	$	167,038
Year Ended December 31, 2010	$	27.54		22.78	%		1.30	%		1.30	%(c)		(0.64	)%		32	%	$	214,097
Class B
Year Ended December 31, 2014	$	25.27		2.37	%		2.26	%		2.26	%		(1.55	)%		12	%	$	234
Year Ended December 31, 2013	$	30.70		31.28	%		2.15	%		2.15	%		(1.33	)%		17	%	$	567
Year Ended December 31, 2012	$	25.81		17.87	%		1.99	%(b)		1.99	%(b)(c)		(0.71	)%		14	%	$	1,056
Year Ended December 31, 2011	$	23.98		(5.68	)%		1.92	%		1.92	%(c)		(1.42	)%		20	%	$	2,253
Year Ended December 31, 2010	$	25.60		21.96	%		1.98	%		1.98	%(c)		(1.37	)%		32	%	$	9,222
Class C
Year Ended December 31, 2014	$	24.98		2.67	%		2.00	%		2.00	%		(1.26	)%		12	%	$	36,476
Year Ended December 31, 2013	$	30.33		31.47	%		2.00	%		2.00	%		(1.14	)%		17	%	$	40,395
Year Ended December 31, 2012	$	25.49		17.82	%		2.05	%(b)		2.05	%(b)(c)		(0.61	)%		14	%	$	31,410
Year Ended December 31, 2011	$	23.72		(5.92	)%		2.05	%		2.05	%(c)		(1.53	)%		20	%	$	30,584
Year Ended December 31, 2010	$	25.39		21.83	%		2.08	%		2.08	%(c)		(1.41	)%		32	%	$	36,101
Class I
Year Ended December 31, 2014	$	31.19		3.80	%		0.88	%		0.88	%		(0.17	)%		12	%	$	2
Year Ended December 31, 2013	$	35.99		32.93	%		0.90	%		0.90	%		(0.04	)%		17	%	$	4
Year Ended December 31, 2012	$	29.47		19.10	%		0.96	%		0.96	%(c)		(0.33	)%		14	%	$	3
Year Ended December 31, 2011	$	27.00		(4.88	)%		0.94	%		0.94	%(c)		(0.47	)%		20	%	$	2,635
Year Ended December 31, 2010 (d)	$	28.56		17.82	%		0.94	%(e)		0.94	%(c)(e)		(0.35	)%(e)		32	%	$	28,993
Class R4
Year Ended December 31, 2014	$	31.70		3.60	%		1.07	%		1.07	%		(0.32	)%		12	%	$	7,952
Year Ended December 31, 2013	$	36.55		32.80	%		1.00	%		1.00	%		0.01	%		17	%	$	6,441
Year Ended December 31, 2012 (g)	$	29.92		8.06	%		1.14	%(b)(e)		1.14	%(b)(c)(e)		1.51	%(e)		14	%	$	15
Class R5
Year Ended December 31, 2014	$	31.71		3.68	%		0.99	%		0.99	%		(0.17	)%		12	%	$	36,689
Year Ended December 31, 2013	$	36.53		32.83	%		0.97	%		0.97	%		0.06	%		17	%	$	6,068
Year Ended December 31, 2012 (h)	$	29.90		8.06	%		1.12	%(e)		1.12	%(c)(e)		1.53	%(e)		14	%	$	2
Class Y
Year Ended December 31, 2014	$	31.80		3.76	%		0.93	%		0.93	%		(0.19	)%		12	%	$	35,551
Year Ended December 31, 2013	$	36.59		32.89	%		0.93	%		0.93	%		0.07	%		17	%	$	48,479
Year Ended December 31, 2012 (i)	$	29.93		8.07	%		1.04	%(e)		1.04	%(c)(e)		1.62	%(e)		14	%	$	2
Class Z
Year Ended December 31, 2014	$	31.03		3.61	%		1.08	%		1.08	%		(0.34	)%		12	%	$	1,132,223
Year Ended December 31, 2013	$	35.90		32.72	%		1.06	%		1.06	%		(0.20	)%		17	%	$	1,496,775
Year Ended December 31, 2012	$	29.45		18.98	%		1.07	%(b)		1.07	%(b)(c)		0.36	%		14	%	$	1,415,442
Year Ended December 31, 2011	$	26.98		(4.95	)%		1.00	%		1.00	%(c)		(0.48	)%		20	%	$	1,355,934
Year Ended December 31, 2010	$	28.56		23.16	%		1.01	%		1.01	%(c)		(0.34	)%		32	%	$	1,410,133

See accompanying notes to financial statements.

107

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn International Select^SM

			Income from Investment Operations									Less Distributions to Shareholders
(Selected data for a share outstanding throughout each period)	Net Asset Value, Beginning of Period		Net investment income (loss)			Net realized and unrealized gain (loss)			Total from investment operations			Net investment income			Net realized gains			Total Distributions to Shareholders			Redemption fees added to paid in capital
Class A
Year Ended December 31, 2014	$	26.91		0.29			(2.17	)		(1.88	)		(0.10	)		(2.89	)		(2.99	)		—
Year Ended December 31, 2013	$	25.61		0.29			3.29			3.58			(0.37	)		(1.91	)		(2.28	)		—
Year Ended December 31, 2012	$	24.26		0.39			4.92			5.31			(1.75	)		(2.21	)		(3.96	)		—
Year Ended December 31, 2011	$	28.01		0.18			(2.95	)		(2.77	)		(0.59	)		(0.39	)		(0.98	)		—
Year Ended December 31, 2010	$	23.39		0.08			4.84			4.92			(0.30	)		—			(0.30	)		0.00	(e)
Class B
Year Ended December 31, 2014	$	25.53		0.10			(2.05	)		(1.95	)		—			(2.89	)		(2.89	)		—
Year Ended December 31, 2013	$	24.40		0.11			3.12			3.23			(0.19	)		(1.91	)		(2.10	)		—
Year Ended December 31, 2012	$	23.27		0.23			4.69			4.92			(1.58	)		(2.21	)		(3.79	)		—
Year Ended December 31, 2011	$	26.72		0.01			(2.82	)		(2.81	)		(0.25	)		(0.39	)		(0.64	)		—
Year Ended December 31, 2010	$	22.34		(0.06	)		4.62			4.56			(0.18	)		—			(0.18	)		0.00	(e)
Class C
Year Ended December 31, 2014	$	25.39		0.07			(2.03	)		(1.96	)		—			(2.89	)		(2.89	)		—
Year Ended December 31, 2013	$	24.28		0.08			3.10			3.18			(0.16	)		(1.91	)		(2.07	)		—
Year Ended December 31, 2012	$	23.17		0.18			4.67			4.85			(1.53	)		(2.21	)		(3.74	)		—
Year Ended December 31, 2011	$	26.58		(0.04	)		(2.81	)		(2.85	)		(0.17	)		(0.39	)		(0.56	)		—
Year Ended December 31, 2010	$	22.21		(0.10	)		4.60			4.50			(0.13	)		—			(0.13	)		0.00	(e)
Class I
Year Ended December 31, 2014	$	27.19		0.39			(2.20	)		(1.81	)		(0.20	)		(2.89	)		(3.09	)		—
Year Ended December 31, 2013	$	25.85		0.39			3.32			3.71			(0.46	)		(1.91	)		(2.37	)		—
Year Ended December 31, 2012	$	24.45		0.51			4.94			5.45			(1.84	)		(2.21	)		(4.05	)		—
Year Ended December 31, 2011	$	28.33		0.31			(2.97	)		(2.66	)		(0.83	)		(0.39	)		(1.22	)		—
Year Ended December 31, 2010 (g)	$	26.11		0.03			2.19			2.22			—			—			—			—
Class R4
Year Ended December 31, 2014	$	27.36		0.37			(2.22	)		(1.85	)		(0.17	)		(2.89	)		(3.06	)		—
Year Ended December 31, 2013	$	25.99		0.29			3.42			3.71			(0.43	)		(1.91	)		(2.34	)		—
Year Ended December 31, 2012 (i)	$	29.98		(0.02	)		(0.09	)(j)		(0.11	)		(1.79	)		(2.09	)		(3.88	)		—
Class R5
Year Ended December 31, 2014	$	27.34		0.36			(2.19	)		(1.83	)		(0.19	)		(2.89	)		(3.08	)		—
Year Ended December 31, 2013	$	25.98		0.38			3.35			3.73			(0.46	)		(1.91	)		(2.37	)		—
Year Ended December 31, 2012 (k)	$	29.98		(0.02	)		(0.09	)(j)		(0.11	)		(1.80	)		(2.09	)		(3.89	)		—
Class Y
Year Ended December 31, 2014	$	27.33		0.40			(2.21	)		(1.81	)		(0.21	)		(2.89	)		(3.10	)		—
Year Ended December 31, 2013	$	25.98		0.11			3.62			3.73			(0.47	)		(1.91	)		(2.38	)		—
Year Ended December 31, 2012 (l)	$	29.99		(0.02	)		(0.09	)(j)		(0.11	)		(1.81	)		(2.09	)		(3.90	)		—
Class Z
Year Ended December 31, 2014	$	27.20		0.38			(2.21	)		(1.83	)		(0.18	)		(2.89	)		(3.07	)		—
Year Ended December 31, 2013	$	25.86		0.37			3.33			3.70			(0.45	)		(1.91	)		(2.36	)		—
Year Ended December 31, 2012	$	24.46		0.49			4.95			5.44			(1.83	)		(2.21	)		(4.04	)		—
Year Ended December 31, 2011	$	28.33		0.29			(2.98	)		(2.69	)		(0.79	)		(0.39	)		(1.18	)		—
Year Ended December 31, 2010	$	23.64		0.18			4.89			5.07			(0.38	)		—			(0.38	)		0.00	(e)

Notes to Financial Highlights

(b) Ratios include line of credit interest expense which is less than 0.01%.

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

(e) Rounds to zero.

(f) Had the Investment Manager and/or its affiliates not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(g) Class I shares commenced operations on September 27, 2010. Per share data and total return reflect activity from that date.

(h) Annualized.

(i) Class R4 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(j) Calculation of the net gain (loss) per share (both realized and unrealized) does not correlate to the aggregate realized and unrealized gain (loss) presented in the Statements of Operations due to the timing of subscriptions and redemptions of Fund shares in relation to fluctuations in the market value of the portfolio.

(k) Class R5 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(l) Class Y shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

See accompanying notes to financial statements.

108

									Ratio to Average Net Assets									Supplemental Data
(Selected data for a share outstanding throughout each period)	Increase from regulatory settlements			Net Asset Value, End of Period		Total Return			Total gross expenses (a)			Total net expenses (a)			Net investment income (loss)			Portfolio turnover rate			Net assets, end of period (000s)
Class A
Year Ended December 31, 2014		—		$	22.04		(7.06	)%		1.47	%		1.47	%		1.05	%		58	%	$	53,419
Year Ended December 31, 2013		—		$	26.91		14.42	%		1.47	%		1.47	%		1.08	%		72	%	$	73,911
Year Ended December 31, 2012		—		$	25.61		22.05	%		1.49	%(b)		1.49	%(b)(c)		1.43	%		63	%	$	74,167
Year Ended December 31, 2011		—		$	24.26		(10.11	)%		1.51	%		1.51	%(d)		0.66	%		44	%	$	56,350
Year Ended December 31, 2010		0.00	(e)	$	28.01		21.41	%		1.56	%		1.56	%(d)		0.33	%		42	%	$	71,668
Class B
Year Ended December 31, 2014		—		$	20.69		(7.71	)%		2.11	%		2.11	%		0.39	%		58	%	$	355
Year Ended December 31, 2013		—		$	25.53		13.67	%		2.14	%		2.14	%		0.43	%		72	%	$	873
Year Ended December 31, 2012		—		$	24.40		21.29	%		2.11	%(b)		2.10	%(b)(c)		0.87	%		63	%	$	1,250
Year Ended December 31, 2011		—		$	23.27		(10.64	)%		2.14	%		2.14	%(d)		0.04	%		44	%	$	1,774
Year Ended December 31, 2010		0.00	(e)	$	26.72		20.63	%(f)		2.24	%		2.20	%(d)		(0.27	)%		42	%	$	3,030
Class C
Year Ended December 31, 2014		—		$	20.54		(7.80	)%		2.23	%		2.23	%		0.29	%		58	%	$	8,057
Year Ended December 31, 2013		—		$	25.39		13.52	%		2.26	%		2.26	%		0.32	%		72	%	$	10,311
Year Ended December 31, 2012		—		$	24.28		21.10	%		2.28	%(b)		2.27	%(b)(c)		0.67	%		63	%	$	9,786
Year Ended December 31, 2011		—		$	23.17		(10.81	)%		2.31	%		2.31	%(d)		(0.14	)%		44	%	$	8,704
Year Ended December 31, 2010		0.00	(e)	$	26.58		20.45	%		2.36	%		2.36	%(d)		(0.45	)%		42	%	$	11,885
Class I
Year Ended December 31, 2014		—		$	22.29		(6.72	)%		1.11	%		1.11	%		1.41	%		58	%	$	2
Year Ended December 31, 2013		—		$	27.19		14.82	%		1.13	%		1.13	%		1.43	%		72	%	$	3
Year Ended December 31, 2012		—		$	25.85		22.48	%		1.15	%		1.14	%(c)		1.84	%		63	%	$	2
Year Ended December 31, 2011		—		$	24.45		(9.68	)%		1.04	%		1.04	%(d)		1.12	%		44	%	$	2
Year Ended December 31, 2010 (g)		—		$	28.33		8.50	%		1.14	%(h)		1.14	%(d)(h)		0.44	%(h)		42	%	$	3
Class R4
Year Ended December 31, 2014		—		$	22.45		(6.83	)%		1.21	%		1.21	%		1.33	%		58	%	$	974
Year Ended December 31, 2013		—		$	27.36		14.72	%		1.24	%		1.24	%		1.06	%		72	%	$	417
Year Ended December 31, 2012 (i)		—		$	25.99		(0.27	)%		1.30	%(b)(h)		1.30	%(b)(c)(h)		(0.55	)%(h)		63	%	$	13
Class R5
Year Ended December 31, 2014		—		$	22.43		(6.77	)%		1.15	%		1.15	%		1.30	%		58	%	$	2,593
Year Ended December 31, 2013		—		$	27.34		14.80	%(f)		1.15	%		1.15	%		1.40	%		72	%	$	956
Year Ended December 31, 2012 (k)		—		$	25.98		(0.27	)%		1.29	%(h)		1.28	%(c)(h)		(0.55	)%(h)		63	%	$	2
Class Y
Year Ended December 31, 2014		—		$	22.42		(6.71	)%		1.09	%		1.09	%		1.43	%		58	%	$	11,755
Year Ended December 31, 2013		—		$	27.33		14.82	%		1.09	%		1.09	%		0.40	%		72	%	$	13,318
Year Ended December 31, 2012 (l)		—		$	25.98		(0.25	)%		1.21	%(h)		1.20	%(c)(h)		(0.48	)%(h)		63	%	$	2
Class Z
Year Ended December 31, 2014		—		$	22.30		(6.79	)%		1.17	%		1.17	%		1.36	%		58	%	$	175,764
Year Ended December 31, 2013		—		$	27.20		14.75	%		1.19	%		1.19	%		1.37	%		72	%	$	256,100
Year Ended December 31, 2012		—		$	25.86		22.42	%		1.20	%(b)		1.19	%(b)(c)		1.77	%		63	%	$	295,231
Year Ended December 31, 2011		—		$	24.46		(9.76	)%		1.14	%		1.14	%(d)		1.03	%		44	%	$	259,553
Year Ended December 31, 2010		0.00	(e)	$	28.33		21.89	%		1.16	%		1.16	%(d)		0.75	%		42	%	$	366,081

See accompanying notes to financial statements.

109

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn Select^SM

			Income from Investment Operations												Less Distributions to Shareholders
(Selected data for a share outstanding throughout each period)	Net Asset Value, Beginning of Period		Net investment income (loss)			Net realized and unrealized gain (loss)			Reimbursement from affiliate			Total from investment operations			Net investment income			Net realized gains			Total Distributions to Shareholders
Class A
Year Ended December 31, 2014	$	25.57		(0.14	)		0.64			—			0.50			—			(5.04	)		(5.04	)
Year Ended December 31, 2013	$	24.72		(0.15	)		7.92			—			7.77			(0.07	)		(6.85	)		(6.92	)
Year Ended December 31, 2012	$	22.95		0.03			3.78			—			3.81			—			(2.04	)		(2.04	)
Year Ended December 31, 2011	$	27.94		(0.15	)		(4.46	)		—			(4.61	)		(0.38	)		—			(0.38	)
Year Ended December 31, 2010	$	22.81		(0.18	)		5.31			—			5.13			—			—			—
Class B
Year Ended December 31, 2014	$	22.81		(0.31	)		0.57			—			0.26			—			(5.04	)		(5.04	)
Year Ended December 31, 2013	$	22.75		(0.33	)		7.24			—			6.91			—			(6.85	)		(6.85	)
Year Ended December 31, 2012	$	21.40		(0.15	)		3.54			—			3.39			—			(2.04	)		(2.04	)
Year Ended December 31, 2011	$	26.06		(0.30	)		(4.13	)		—			(4.43	)		(0.23	)		—			(0.23	)
Year Ended December 31, 2010	$	21.41		(0.31	)		4.96			—			4.65			—			—			—
Class C
Year Ended December 31, 2014	$	22.46		(0.28	)		0.55			—			0.27			—			(5.04	)		(5.04	)
Year Ended December 31, 2013	$	22.48		(0.32	)		7.15			—			6.83			—			(6.85	)		(6.85	)
Year Ended December 31, 2012	$	21.20		(0.14	)		3.46			—			3.32			—			(2.04	)		(2.04	)
Year Ended December 31, 2011	$	25.83		(0.32	)		(4.12	)		—			(4.44	)		(0.19	)		—			(0.19	)
Year Ended December 31, 2010	$	21.25		(0.34	)		4.92			—			4.58			—			—			—
Class I
Year Ended December 31, 2014	$	26.81		(0.05	)		0.66			—			0.61			—			(5.04	)		(5.04	)
Year Ended December 31, 2013	$	25.63		(0.06	)		8.25			—			8.19			(0.16	)		(6.85	)		(7.01	)
Year Ended December 31, 2012	$	23.65		0.23			3.79			—			4.02			—			(2.04	)		(2.04	)
Year Ended December 31, 2011	$	28.74		(0.03	)		(4.59	)		—			(4.62	)		(0.47	)		—			(0.47	)
Year Ended December 31, 2010 (e)	$	24.74		0.01			3.99			—			4.00			—			—			—
Class R4
Year Ended December 31, 2014	$	27.20		(0.10	)		0.69			—			0.59			—			(5.04	)		(5.04	)
Year Ended December 31, 2013	$	25.92		(0.06	)		8.32			—			8.26			(0.13	)		(6.85	)		(6.98	)
Year Ended December 31, 2012 (g)	$	25.91		0.00	(h)		1.52			—			1.52			—			(1.51	)		(1.51	)
Class R5
Year Ended December 31, 2014	$	27.20		(0.07	)		0.69			—			0.62			—			(5.04	)		(5.04	)
Year Ended December 31, 2013	$	25.93		(0.04	)		8.31			—			8.27			(0.15	)		(6.85	)		(7.00	)
Year Ended December 31, 2012 (i)	$	25.91		0.00	(h)		1.53			—			1.53			—			(1.51	)		(1.51	)
Class Y
Year Ended December 31, 2014	$	27.27		(0.06	)		0.69			—			0.63			—			(5.04	)		(5.04	)
Year Ended December 31, 2013	$	25.98		(0.03	)		8.34			—			8.31			(0.17	)		(6.85	)		(7.02	)
Year Ended December 31, 2012 (j)	$	25.96		0.01			1.52			—			1.53			—			(1.51	)		(1.51	)
Class Z
Year Ended December 31, 2014	$	26.72		(0.08	)		0.68			—			0.60			—			(5.04	)		(5.04	)
Year Ended December 31, 2013	$	25.57		(0.07	)		8.21			—			8.14			(0.14	)		(6.85	)		(6.99	)
Year Ended December 31, 2012	$	23.62		0.11			3.88			—			3.99			—			(2.04	)		(2.04	)
Year Ended December 31, 2011	$	28.73		(0.07	)		(4.58	)		0.00	(h)		(4.65	)		(0.46	)		—			(0.46	)
Year Ended December 31, 2010	$	23.38		(0.10	)		5.45			—			5.35			—			—			—

Notes to Financial Highlights

(b) Ratios include line of credit interest expense which is less than 0.01%.

(d) Had the Investment Manager and/or its affiliates not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(e) Class I shares commenced operations on September 27, 2010. Per share data and total return reflect activity from that date.

(f) Annualized.

(g) Class R4 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(h) Rounds to zero.

(i) Class R5 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(j) Class Y shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(k) During the year ended December 31, 2011, the Fund received a reimbursement from an affiliate. Had the Fund not received this payment, the total return would have been lower by 0.01%.

See accompanying notes to financial statements.

110

						Ratio to Average Net Assets									Supplemental Data
(Selected data for a share outstanding throughout each period)	Net Asset Value, End of Period		Total Return			Total gross expenses (a)			Total net expenses (a)			Net investment income (loss)			Portfolio turnover rate			Net assets, end of period (000s)
Class A
Year Ended December 31, 2014	$	21.03		2.17	%		1.32	%		1.32	%		(0.58	)%		17	%	$	264,234
Year Ended December 31, 2013	$	25.57		33.77	%		1.31	%(b)		1.31	%(b)		(0.54	)%		20	%	$	333,193
Year Ended December 31, 2012	$	24.72		16.87	%		1.31	%(b)		1.31	%(b)(c)		0.13	%		15	%	$	271,628
Year Ended December 31, 2011	$	22.95		(16.65	)%		1.28	%		1.28	%(c)		(0.57	)%		21	%	$	340,325
Year Ended December 31, 2010	$	27.94		22.49	%		1.28	%		1.28	%(c)		(0.73	)%		28	%	$	555,263
Class B
Year Ended December 31, 2014	$	18.03		1.35	%(d)		2.14	%		2.10	%		(1.40	)%		17	%	$	1,014
Year Ended December 31, 2013	$	22.81		32.81	%(d)		2.05	%(b)		2.03	%(b)		(1.32	)%		20	%	$	2,938
Year Ended December 31, 2012	$	22.75		16.11	%		1.91	%(b)		1.90	%(b)(c)		(0.62	)%		15	%	$	9,938
Year Ended December 31, 2011	$	21.40		(17.11	)%		1.88	%		1.88	%(c)		(1.21	)%		21	%	$	26,126
Year Ended December 31, 2010	$	26.06		21.72	%		1.92	%		1.92	%(c)		(1.39	)%		28	%	$	72,203
Class C
Year Ended December 31, 2014	$	17.69		1.42	%		2.04	%		2.04	%		(1.30	)%		17	%	$	48,591
Year Ended December 31, 2013	$	22.46		32.85	%		2.04	%(b)		2.04	%(b)		(1.28	)%		20	%	$	61,537
Year Ended December 31, 2012	$	22.48		15.93	%		2.07	%(b)		2.06	%(b)(c)		(0.59	)%		15	%	$	57,309
Year Ended December 31, 2011	$	21.20		(17.27	)%		2.05	%		2.05	%(c)		(1.34	)%		21	%	$	62,887
Year Ended December 31, 2010	$	25.83		21.55	%		2.07	%		2.07	%(c)		(1.52	)%		28	%	$	98,445
Class I
Year Ended December 31, 2014	$	22.38		2.49	%		0.94	%		0.94	%		(0.20	)%		17	%	$	18,718
Year Ended December 31, 2013	$	26.81		34.31	%		0.94	%(b)		0.94	%(b)		(0.21	)%		20	%	$	13,660
Year Ended December 31, 2012	$	25.63		17.26	%		0.96	%(b)		0.95	%(b)(c)		0.89	%		15	%	$	39,054
Year Ended December 31, 2011	$	23.65		(16.25	)%		0.92	%		0.92	%(c)		(0.12	)%		21	%	$	10,944
Year Ended December 31, 2010 (e)	$	28.74		16.17	%		0.91	%(f)		0.91	%(c)(f)		0.18	%(f)		28	%	$	7,832
Class R4
Year Ended December 31, 2014	$	22.75		2.39	%		1.12	%		1.12	%		(0.37	)%		17	%	$	1,193
Year Ended December 31, 2013	$	27.20		34.16	%		1.02	%(b)		1.02	%(b)		(0.20	)%		20	%	$	1,383
Year Ended December 31, 2012 (g)	$	25.92		5.92	%		1.07	%(f)		1.06	%(c)(f)		0.02	%(f)		15	%	$	15
Class R5
Year Ended December 31, 2014	$	22.78		2.50	%		1.00	%		1.00	%		(0.26	)%		17	%	$	10,697
Year Ended December 31, 2013	$	27.20		34.21	%		0.97	%(b)		0.97	%(b)		(0.13	)%		20	%	$	11,996
Year Ended December 31, 2012 (i)	$	25.93		5.96	%		0.99	%(f)		0.99	%(c)(f)		0.08	%(f)		15	%	$	3
Class Y
Year Ended December 31, 2014	$	22.86		2.53	%		0.95	%		0.95	%		(0.22	)%		17	%	$	3,644
Year Ended December 31, 2013	$	27.27		34.30	%		0.93	%(b)		0.93	%(b)		(0.09	)%		20	%	$	4,847
Year Ended December 31, 2012 (j)	$	25.98		5.94	%		0.92	%(f)		0.92	%(c)(f)		0.15	%(f)		15	%	$	3
Class Z
Year Ended December 31, 2014	$	22.28		2.47	%		1.04	%		1.04	%		(0.30	)%		17	%	$	318,487
Year Ended December 31, 2013	$	26.72		34.16	%		1.02	%(b)		1.02	%(b)		(0.26	)%		20	%	$	431,990
Year Ended December 31, 2012	$	25.57		17.15	%		1.03	%(b)		1.03	%(b)(c)		0.40	%		15	%	$	587,678
Year Ended December 31, 2011	$	23.62		(16.37	)%(k)		0.97	%		0.97	%(c)		(0.28	)%		21	%	$	850,338
Year Ended December 31, 2010	$	28.73		22.88	%		0.97	%		0.97	%(c)		(0.41	)%		28	%	$	1,549,112

See accompanying notes to financial statements.

111

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Thermostat Fund^SM

			Income from Investment Operations						Less Distributions to Shareholders
(Selected data for a share outstanding throughout each period)	Net Asset Value, Beginning of Period		Net investment income		Net realized and unrealized gain		Total from investment operations		Net investment income			Net realized gains			Total Distributions to Shareholders
Class A
Year Ended December 31, 2014	$	14.58		0.28		0.49		0.77		(0.28	)		(0.21	)		(0.49	)
Year Ended December 31, 2013	$	14.29		0.29		1.00		1.29		(0.25	)		(0.75	)		(1.00	)
Year Ended December 31, 2012	$	12.82		0.32		1.39		1.71		(0.24	)		—			(0.24	)
Year Ended December 31, 2011	$	12.58		0.28		0.30		0.58		(0.34	)		—			(0.34	)
Year Ended December 31, 2010	$	10.90		0.19		1.67		1.86		(0.18	)		—			(0.18	)
Class B
Year Ended December 31, 2014	$	14.68		0.21		0.50		0.71		(0.21	)		(0.21	)		(0.42	)
Year Ended December 31, 2013	$	14.39		0.19		1.03		1.22		(0.18	)		(0.75	)		(0.93	)
Year Ended December 31, 2012	$	12.91		0.20		1.45		1.65		(0.17	)		—			(0.17	)
Year Ended December 31, 2011	$	12.64		0.15		0.38		0.53		(0.26	)		—			(0.26	)
Year Ended December 31, 2010	$	10.93		0.13		1.67		1.80		(0.09	)		—			(0.09	)
Class C
Year Ended December 31, 2014	$	14.68		0.17		0.49		0.66		(0.17	)		(0.21	)		(0.38	)
Year Ended December 31, 2013	$	14.39		0.18		1.00		1.18		(0.14	)		(0.75	)		(0.89	)
Year Ended December 31, 2012	$	12.91		0.22		1.39		1.61		(0.13	)		—			(0.13	)
Year Ended December 31, 2011	$	12.62		0.18		0.31		0.49		(0.20	)		—			(0.20	)
Year Ended December 31, 2010	$	10.91		0.10		1.68		1.78		(0.07	)		—			(0.07	)
Class R4
Year Ended December 31, 2014	$	14.46		0.32		0.49		0.81		(0.32	)		(0.21	)		(0.53	)
Year Ended December 31, 2013	$	14.19		0.36		0.95		1.31		(0.29	)		(0.75	)		(1.04	)
Year Ended December 31, 2012 (d)	$	14.08		0.09		0.28		0.37		(0.26	)		—			(0.26	)
Class R5
Year Ended December 31, 2014	$	14.47		0.31		0.50		0.81		(0.32	)		(0.21	)		(0.53	)
Year Ended December 31, 2013	$	14.19		0.37		0.96		1.33		(0.30	)		(0.75	)		(1.05	)
Year Ended December 31, 2012 (f)	$	14.08		0.09		0.27		0.36		(0.25	)		—			(0.25	)
Class Y
Year Ended December 31, 2014	$	14.46		0.32		0.50		0.82		(0.33	)		(0.21	)		(0.54	)
Year Ended December 31, 2013	$	14.18		0.33		1.01		1.34		(0.31	)		(0.75	)		(1.06	)
Year Ended December 31, 2012 (g)	$	14.08		0.09		0.27		0.36		(0.26	)		—			(0.26	)
Class Z
Year Ended December 31, 2014	$	14.40		0.32		0.48		0.80		(0.32	)		(0.21	)		(0.53	)
Year Ended December 31, 2013	$	14.13		0.32		0.99		1.31		(0.29	)		(0.75	)		(1.04	)
Year Ended December 31, 2012	$	12.67		0.34		1.39		1.73		(0.27	)		—			(0.27	)
Year Ended December 31, 2011	$	12.44		0.31		0.29		0.60		(0.37	)		—			(0.37	)
Year Ended December 31, 2010	$	10.80		0.21		1.66		1.87		(0.23	)		—			(0.23	)

Notes to Financial Highlights

(a) Had the Investment Manager and/or its affiliates not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(b) In addition to the fees and expenses that the Fund bears directly, the Fund indirectly bears a pro rata share of the fees and expenses of the underlying funds in which the Fund invests, if any. Such indirect expenses are not included in the Fund's reported expense ratios.

(d) Class R4 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(e) Annualized.

(f) Class R5 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(g) Class Y shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

See accompanying notes to financial statements.

112

						Ratio to Average Net Assets									Supplemental Data
(Selected data for a share outstanding throughout each period)	Net Asset Value, End of Period		Total Return (a)			Total gross expenses (b)			Total net expenses (b)			Net investment income			Portfolio turnover rate			Net assets, end of period (000s)
Class A
Year Ended December 31, 2014	$	14.86		5.30	%		0.51	%		0.50	%		1.88	%		95	%	$	450,258
Year Ended December 31, 2013	$	14.58		9.07	%		0.52	%		0.50	%		1.91	%		92	%	$	513,293
Year Ended December 31, 2012	$	14.29		13.34	%		0.58	%		0.50	%(c)		2.28	%		109	%	$	323,750
Year Ended December 31, 2011	$	12.82		4.62	%		0.67	%		0.50	%(c)		2.17	%		130	%	$	79,744
Year Ended December 31, 2010	$	12.58		17.28	%		0.72	%		0.50	%(c)		1.64	%		118	%	$	44,527
Class B
Year Ended December 31, 2014	$	14.97		4.83	%		1.15	%		1.00	%		1.39	%		95	%	$	1,231
Year Ended December 31, 2013	$	14.68		8.49	%		1.15	%		1.00	%		1.29	%		92	%	$	2,263
Year Ended December 31, 2012	$	14.39		12.78	%		1.16	%		1.00	%(c)		1.47	%		109	%	$	4,480
Year Ended December 31, 2011	$	12.91		4.19	%		1.23	%		1.00	%(c)		1.18	%		130	%	$	11,318
Year Ended December 31, 2010	$	12.64		16.64	%		1.28	%		1.00	%(c)		1.10	%		118	%	$	28,752
Class C
Year Ended December 31, 2014	$	14.96		4.50	%		1.26	%		1.25	%		1.14	%		95	%	$	404,456
Year Ended December 31, 2013	$	14.68		8.23	%		1.27	%		1.25	%		1.16	%		92	%	$	430,173
Year Ended December 31, 2012	$	14.39		12.52	%		1.32	%		1.25	%(c)		1.56	%		109	%	$	253,641
Year Ended December 31, 2011	$	12.91		3.87	%		1.43	%		1.25	%(c)		1.40	%		130	%	$	33,378
Year Ended December 31, 2010	$	12.62		16.43	%		1.49	%		1.25	%(c)		0.88	%		118	%	$	21,866
Class R4
Year Ended December 31, 2014	$	14.74		5.61	%		0.26	%		0.25	%		2.14	%		95	%	$	23,412
Year Ended December 31, 2013	$	14.46		9.26	%		0.28	%		0.25	%		2.39	%		92	%	$	14,651
Year Ended December 31, 2012 (d)	$	14.19		2.60	%		0.42	%(e)		0.25	%(c)(e)		4.59	%(e)		109	%	$	15
Class R5
Year Ended December 31, 2014	$	14.75		5.62	%		0.24	%		0.23	%		2.11	%		95	%	$	3,536
Year Ended December 31, 2013	$	14.47		9.35	%		0.25	%		0.23	%		2.44	%		92	%	$	979
Year Ended December 31, 2012 (f)	$	14.19		2.58	%		0.35	%(e)		0.27	%(c)(e)		4.60	%(e)		109	%	$	3
Class Y
Year Ended December 31, 2014	$	14.74		5.68	%		0.19	%		0.18	%		2.19	%		95	%	$	401
Year Ended December 31, 2013	$	14.46		9.46	%		0.14	%		0.14	%		2.23	%		92	%	$	3
Year Ended December 31, 2012 (g)	$	14.18		2.55	%		0.30	%(e)		0.22	%(c)(e)		4.63	%(e)		109	%	$	3
Class Z
Year Ended December 31, 2014	$	14.67		5.57	%		0.25	%		0.24	%		2.16	%		95	%	$	377,119
Year Ended December 31, 2013	$	14.40		9.30	%		0.26	%		0.25	%		2.14	%		92	%	$	375,444
Year Ended December 31, 2012	$	14.13		13.69	%		0.30	%		0.25	%(c)		2.48	%		109	%	$	292,732
Year Ended December 31, 2011	$	12.67		4.85	%		0.34	%		0.25	%(c)		2.43	%		130	%	$	65,167
Year Ended December 31, 2010	$	12.44		17.58	%		0.37	%		0.25	%(c)		1.87	%		118	%	$	36,130

See accompanying notes to financial statements.

113

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn Emerging Markets Fund^SM

			Income from Investment Operations									Less Distributions to Shareholders
(Selected data for a share outstanding throughout each period)	Net Asset Value, Beginning of Period		Net investment income (loss)			Net realized and unrealized gain (loss)			Total from investment operations			Net investment income			Total Distributions to Shareholders			Net Asset Value, End of Period
Class A
Year Ended December 31, 2014	$	13.37		0.06			(0.63	)		(0.57	)		(0.08	)		(0.08	)	$	12.72
Year Ended December 31, 2013	$	12.04		0.07			1.34			1.41			(0.08	)		(0.08	)	$	13.37
Year Ended December 31, 2012	$	9.26		0.08			2.78			2.86			(0.08	)		(0.08	)	$	12.04
Year Ended December 31, 2011 (d)	$	10.00		(0.00	)(e)		(0.74	)		(0.74	)		—			—		$	9.26
Class C
Year Ended December 31, 2014	$	13.32		(0.05	)		(0.62	)		(0.67	)		—			—		$	12.65
Year Ended December 31, 2013	$	12.01		(0.03	)		1.34			1.31			—			—		$	13.32
Year Ended December 31, 2012	$	9.24		(0.02	)		2.79			2.77			—			—		$	12.01
Year Ended December 31, 2011 (h)	$	10.00		(0.02	)		(0.74	)		(0.76	)		—			—		$	9.24
Class I
Year Ended December 31, 2014	$	13.41		0.06			(0.60	)		(0.54	)		(0.12	)		(0.12	)	$	12.75
Year Ended December 31, 2013	$	12.08		0.08			1.37			1.45			(0.12	)		(0.12	)	$	13.41
Year Ended December 31, 2012	$	9.29		0.11			2.80			2.91			(0.12	)		(0.12	)	$	12.08
Year Ended December 31, 2011 (i)	$	10.00		0.01			(0.72	)		(0.71	)		—			—		$	9.29
Class R4
Year Ended December 31, 2014	$	13.49		0.09			(0.63	)		(0.54	)		(0.12	)		(0.12	)	$	12.83
Year Ended December 31, 2013	$	12.14		0.12			1.35			1.47			(0.12	)		(0.12	)	$	13.49
Year Ended December 31, 2012 (j)	$	11.44		(0.01	)		0.81			0.80			(0.10	)		(0.10	)	$	12.14
Class R5
Year Ended December 31, 2014	$	13.48		0.10			(0.64	)		(0.54	)		(0.12	)		(0.12	)	$	12.82
Year Ended December 31, 2013	$	12.14		0.12			1.34			1.46			(0.12	)		(0.12	)	$	13.48
Year Ended December 31, 2012 (k)	$	11.44		(0.00	)(e)		0.81			0.81			(0.11	)		(0.11	)	$	12.14
Class Y
Year Ended December 31, 2014	$	13.36		0.09			(0.62	)		(0.53	)		(0.12	)		(0.12	)	$	12.71
Year Ended December 31, 2013 (l)	$	12.22		0.07			1.20			1.27			(0.13	)		(0.13	)	$	13.36
Class Z
Year Ended December 31, 2014	$	13.40		0.08			(0.63	)		(0.55	)		(0.11	)		(0.11	)	$	12.74
Year Ended December 31, 2013	$	12.07		0.11			1.33			1.44			(0.11	)		(0.11	)	$	13.40
Year Ended December 31, 2012	$	9.28		0.12			2.79			2.91			(0.12	)		(0.12	)	$	12.07
Year Ended December 31, 2011 (m)	$	10.00		0.01			(0.73	)		(0.72	)		—			—		$	9.28

Notes to Financial Highlights

(b) Had the Investment Manager and/or its affiliates not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(d) Class A shares commenced operations on August 19, 2011. Per share data and total return reflect activity from that date.

(e) Rounds to zero.

(f) Annualized.

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

(h) Class C shares commenced operations on August 19, 2011. Per share data and total return reflect activity from that date.

(i) Class I shares commenced operations on August 19, 2011. Per share data and total return reflect activity from that date.

(j) Class R4 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(k) Class R5 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(l) Class Y shares commenced operations on June 13, 2013. Per share data and total return reflect activity from that date.

(m) Class Z shares commenced operations on August 19, 2011. Per share data and total return reflect activity from that date.

See accompanying notes to financial statements.

114

				Ratio to Average Net Assets									Supplemental Data
(Selected data for a share outstanding throughout each period)	Total Return			Total gross expenses			Total net expenses			Net investment income (loss)			Portfolio turnover rate			Net assets, end of period (000s)
Class A
Year Ended December 31, 2014		(4.28	)%		1.56	%(a)		1.56	%(a)		0.42	%		45	%	$	160,969
Year Ended December 31, 2013		11.73	%(b)		1.80	%(a)		1.76	%(a)		0.52	%		36	%	$	177,158
Year Ended December 31, 2012		30.86	%(b)		6.42	%(a)		1.77	%(a)(c)		0.77	%		30	%	$	3,103
Year Ended December 31, 2011 (d)		(7.40	)%(b)		20.13	%(f)		1.85	%(f)(g)		(0.01	)%(f)		9	%	$	332
Class C
Year Ended December 31, 2014		(5.03	)%		2.33	%(a)		2.33	%(a)		(0.36	)%		45	%	$	41,208
Year Ended December 31, 2013		10.91	%(b)		2.55	%(a)		2.51	%(a)		(0.23	)%		36	%	$	32,636
Year Ended December 31, 2012		29.98	%(b)		7.18	%(a)		2.56	%(a)(c)		(0.15	)%		30	%	$	615
Year Ended December 31, 2011 (h)		(7.60	)%(b)		25.06	%(f)		2.60	%(f)(g)		(0.68	)%(f)		9	%	$	127
Class I
Year Ended December 31, 2014		(4.01	)%		1.22	%(a)		1.22	%(a)		0.44	%		45	%	$	3
Year Ended December 31, 2013		12.06	%(b)		1.73	%(a)		1.39	%(a)		0.65	%		36	%	$	7
Year Ended December 31, 2012		31.39	%(b)		6.18	%(a)		1.41	%(a)(c)		1.05	%		30	%	$	6
Year Ended December 31, 2011 (i)		(7.10	)%(b)		19.31	%(f)		1.41	%(f)(g)		0.17	%(f)		9	%	$	5
Class R4
Year Ended December 31, 2014		(4.03	)%		1.28	%(a)		1.28	%(a)		0.66	%		45	%	$	15,467
Year Ended December 31, 2013		12.13	%(b)		1.44	%(a)		1.44	%(a)		0.92	%		36	%	$	13,583
Year Ended December 31, 2012 (j)		7.04	%(b)		5.86	%(a)(f)		1.54	%(a)(c)(f)		(0.31	)%(f)		30	%	$	16
Class R5
Year Ended December 31, 2014		(4.02	)%		1.26	%(a)		1.26	%(a)		0.72	%		45	%	$	19,632
Year Ended December 31, 2013		12.07	%(b)		1.42	%(a)		1.42	%(a)		0.94	%		36	%	$	13,625
Year Ended December 31, 2012 (k)		7.11	%(b)		5.81	%(a)(f)		1.46	%(a)(c)(f)		(0.22	)%(f)		30	%	$	3
Class Y
Year Ended December 31, 2014		(3.95	)%		1.22	%(a)		1.22	%(a)		0.68	%		45	%	$	2
Year Ended December 31, 2013 (l)		10.43	%(b)		1.36	%(a)(f)		1.36	%(a)(f)		0.97	%(f)		36	%	$	3
Class Z
Year Ended December 31, 2014		(4.12	)%		1.33	%(a)		1.33	%(a)		0.62	%		45	%	$	245,053
Year Ended December 31, 2013		11.92	%(b)		1.58	%(a)		1.54	%(a)		0.89	%		36	%	$	177,693
Year Ended December 31, 2012		31.35	%(b)		6.15	%(a)		1.46	%(a)(c)		1.07	%		30	%	$	6,846
Year Ended December 31, 2011 (m)		(7.20	)%(b)		19.52	%(f)		1.46	%(f)(g)		0.15	%(f)		9	%	$	2,765

See accompanying notes to financial statements.

115

Columbia Acorn Family of Funds

Financial Highlights, continued

Columbia Acorn European Fund^SM

			Income from Investment Operations									Less Distributions to Shareholders
(Selected data for a share outstanding throughout each period)	Net Asset Value, Beginning of Period		Net investment income (loss)			Net realized and unrealized gain (loss)			Total from investment operations			Net investment income			Net realized gains			Total Distributions to Shareholders
Class A
Year Ended December 31, 2014	$	15.68		0.13			(1.34	)		(1.21	)		(0.05	)		(0.08	)		(0.13	)
Year Ended December 31, 2013	$	11.76		(0.02	)		3.97			3.95			(0.01	)		(0.02	)		(0.03	)
Year Ended December 31, 2012	$	9.43		0.03			2.37			2.40			(0.07	)		(0.00	)(c)		(0.07	)
Year Ended December 31, 2011 (e)	$	10.00		(0.03	)		(0.46	)		(0.49	)		(0.06	)		(0.02	)		(0.08	)
Class C
Year Ended December 31, 2014	$	15.54		(0.01	)		(1.29	)		(1.30	)		—			(0.08	)		(0.08	)
Year Ended December 31, 2013	$	11.73		(0.15	)		3.98			3.83			—			(0.02	)		(0.02	)
Year Ended December 31, 2012	$	9.44		(0.15	)		2.46			2.31			(0.02	)		(0.00	)(c)		(0.02	)
Year Ended December 31, 2011 (h)	$	10.00		(0.06	)		(0.45	)		(0.51	)		(0.03	)		(0.02	)		(0.05	)
Class I
Year Ended December 31, 2014	$	15.67		0.11			(1.27	)		(1.16	)		(0.10	)		(0.08	)		(0.18	)
Year Ended December 31, 2013	$	11.75		0.12			3.88			4.00			(0.06	)		(0.02	)		(0.08	)
Year Ended December 31, 2012	$	9.43		0.10			2.32			2.42			(0.10	)		(0.00	)(c)		(0.10	)
Year Ended December 31, 2011 (i)	$	10.00		(0.02	)		(0.46	)		(0.48	)		(0.07	)		(0.02	)		(0.09	)
Class R4
Year Ended December 31, 2014 (j)	$	15.85		(0.02	)		(1.34	)		(1.36	)		(0.09	)		—			(0.09	)
Class R5
Year Ended December 31, 2014	$	15.82		0.14			(1.32	)		(1.18	)		(0.09	)		(0.08	)		(0.17	)
Year Ended December 31, 2013	$	11.86		(0.04	)		4.06			4.02			(0.04	)		(0.02	)		(0.06	)
Year Ended December 31, 2012 (k)	$	11.19		(0.02	)		0.77			0.75			(0.08	)		—			(0.08	)
Class Z
Year Ended December 31, 2014	$	15.68		0.15			(1.32	)		(1.17	)		(0.09	)		(0.08	)		(0.17	)
Year Ended December 31, 2013	$	11.76		0.11			3.88			3.99			(0.05	)		(0.02	)		(0.07	)
Year Ended December 31, 2012	$	9.44		0.08			2.34			2.42			(0.10	)		(0.00	)(c)		(0.10	)
Year Ended December 31, 2011 (l)	$	10.00		(0.02	)		(0.46	)		(0.48	)		(0.06	)		(0.02	)		(0.08	)

Notes to Financial Highlights

(a) Had the Investment Manager and/or its affiliates not waived fees and/or reimbursed a portion of expenses, total return would have been reduced.

(b) In addition to the fees and expenses that the Fund bears directly, the Fund indirectly bears a pro rata share of the fees and expenses of any other funds in which it invests, if any. Such indirect expenses are not included in the Fund's reported expense ratios.

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

(e) Class A shares commenced operations on August 19, 2011. Per share data and total return reflect activity from that date.

(f) Annualized.

(g) The benefits derived from custody fees paid indirectly had an impact of 0.02%.

(h) Class C shares commenced operations on August 19, 2011. Per share data and total return reflect activity from that date.

(i) Class I shares commenced operations on August 19, 2011. Per share data and total return reflect activity from that date.

(j) Class R4 shares commenced operations on June 25, 2014. Per share data and total return reflect activity from that date.

(k) Class R5 shares commenced operations on November 8, 2012. Per share data and total return reflect activity from that date.

(l) Class Z shares commenced operations on August 19, 2011. Per share data and total return reflect activity from that date.

See accompanying notes to financial statements.

116

						Ratio to Average Net Assets									Supplemental Data
(Selected data for a share outstanding throughout each period)	Net Asset Value, End of Period		Total Return (a)			Total gross expenses			Total net expenses			Net investment income (loss)			Portfolio turnover rate			Net assets, end of period (000s)
Class A
Year Ended December 31, 2014	$	14.34		(7.77	)%		2.05	%(b)		1.75	%(b)		0.86	%		74	%	$	21,101
Year Ended December 31, 2013	$	15.68		33.64	%		3.33	%(b)		1.74	%(b)		(0.11	)%		42	%	$	19,078
Year Ended December 31, 2012	$	11.76		25.46	%		12.35	%(b)		1.61	%(b)(d)		0.23	%		37	%	$	453
Year Ended December 31, 2011 (e)	$	9.43		(4.97	)%		33.59	%(f)		1.75	%(f)(g)		(0.84	)%(f)		17	%	$	154
Class C
Year Ended December 31, 2014	$	14.16		(8.44	)%		2.84	%(b)		2.50	%(b)		(0.10	)%		74	%	$	5,096
Year Ended December 31, 2013	$	15.54		32.63	%		4.19	%(b)		2.50	%(b)		(1.10	)%		42	%	$	1,400
Year Ended December 31, 2012	$	11.73		24.46	%		12.83	%(b)		2.32	%(b)(d)		(1.33	)%		37	%	$	89
Year Ended December 31, 2011 (h)	$	9.44		(5.14	)%		35.79	%(f)		2.50	%(f)(g)		(1.66	)%(f)		17	%	$	5
Class I
Year Ended December 31, 2014	$	14.33		(7.49	)%		1.71	%(b)		1.46	%(b)		0.74	%		74	%	$	2
Year Ended December 31, 2013	$	15.67		34.06	%		3.99	%(b)		1.41	%(b)		0.88	%		42	%	$	8
Year Ended December 31, 2012	$	11.75		25.71	%		12.05	%(b)		1.31	%(b)(d)		0.94	%		37	%	$	6
Year Ended December 31, 2011 (i)	$	9.43		(4.81	)%		30.00	%(f)		1.31	%(f)(g)		(0.47	)%(f)		17	%	$	5
Class R4
Year Ended December 31, 2014 (j)	$	14.40		(8.60	)%		1.87	%(b)(f)		1.50	%(b)(f)		(0.30	)%(f)		74	%	$	302
Class R5
Year Ended December 31, 2014	$	14.47		(7.54	)%		1.75	%(b)		1.52	%(b)		0.92	%		74	%	$	1,633
Year Ended December 31, 2013	$	15.82		33.97	%		2.76	%(b)		1.51	%(b)		(0.29	)%		42	%	$	1,891
Year Ended December 31, 2012 (k)	$	11.86		6.70	%		14.07	%(b)(f)		1.36	%(b)(d)(f)		(1.07	)%(f)		37	%	$	3
Class Z
Year Ended December 31, 2014	$	14.34		(7.52	)%		1.79	%(b)		1.50	%(b)		0.97	%		74	%	$	8,499
Year Ended December 31, 2013	$	15.68		33.98	%		3.98	%(b)		1.45	%(b)		0.83	%		42	%	$	4,407
Year Ended December 31, 2012	$	11.76		25.66	%		12.07	%(b)		1.33	%(b)(d)		0.76	%		37	%	$	2,727
Year Ended December 31, 2011 (l)	$	9.44		(4.78	)%		30.26	%(f)		1.37	%(f)(g)		(0.52	)%(f)		17	%	$	1,516

See accompanying notes to financial statements.

117

Columbia Acorn Family of Funds

Notes to Financial Statements

1. Nature of Operations

Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select, Columbia Thermostat Fund, Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund (each a Fund and collectively, the Funds) are each a series of Columbia Acorn Trust (the Trust). The Trust is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as 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 affiliated stock and bond mutual funds (underlying funds) according to the current level of the Standard & Poor's (S&P) 500 Index in relation to predetermined ranges set by Columbia Wanger Asset Management, LLC (the Investment Manager or CWAM). 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. Columbia Acorn Fund, Columbia Acorn USA, Columbia Acorn International Select and Columbia Acorn Select each currently offers Class A, Class B, Class C, Class I, Class R4, Class R5, Class Y and Class Z shares. Columbia Acorn International currently offers Class A, Class B, Class C, Class I, Class R, Class R4, Class R5, Class Y and Class Z shares. Columbia Thermostat Fund currently offers Class A, Class B, Class C, Class R4, Class R5, Class Y and Class Z shares. Columbia Acorn Emerging Markets Fund currently offers Class A, Class C, Class I, Class R4, Class R5, Class Y and Class Z shares. Columbia Acorn European Fund currently offers Class A, Class C, Class I, Class R4, Class R5 and Class Z shares. Effective July 11, 2014, Columbia Acorn Emerging Markets Fund is closed to new investors and new accounts, except as described in the Fund's prospectus, dated May 1, 2014, as supplemented June 12, 2014. Effective February 29, 2008, the Funds generally no longer accept investments by new or existing investors in the Funds' Class B shares, except in connection with the reinvestment of any dividend and/or capital gain distributions in Class B shares of the Funds and exchanges by existing Class B shareholders of certain other funds within the Columbia Acorn Family of Funds.

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 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 purchase, and a 0.50% CDSC if the shares are redeemed more than 12, but less than 18, months after purchase, with certain limited exceptions.

Class B shares are subject to 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 I, Class R, Class R4, Class R5 and Class Y shares are offered at net asset value. There are certain restrictions on who may purchase these share classes.

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 Investment Distributors, Inc. (CMID) at no additional charge.

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 agent fees, 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. Summary of Significant Accounting Policies

>Basis of Preparation

Each Fund is an investment company that applies the accounting and reporting guidance in the Financial Accounting Standards Board (FASB) Accounting Standards Codification Topic 946, Financial Services – Investment Companies (ASC 946). The financial statements are prepared in accordance with U.S. generally accepted accounting principles (GAAP) which 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 income and expenses during the reporting period. Actual results could differ from those estimates.

118

The following is a summary of significant accounting policies 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 (the Board). With respect to Columbia Thermostat Fund, investments in underlying funds are valued at their net asset values as reported by the underlying 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. Exchange traded funds are valued at their closing net asset value as reported on the applicable exchange.

Short-term investments maturing in 60 days or less are valued at amortized cost, which approximates market value.

Forward foreign currency exchange contracts are marked-to-market based upon foreign currency exchange rates provided by a pricing service.

The Trust has 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. A security for which there is no reported sale on the valuation date is valued at the mean of the latest bid and ask quotations.

>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.

>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 Fund 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.

>Derivative instruments

Columbia Acorn International Select invests in forward foreign currency exchange contracts on a limited basis, as detailed below. Forward foreign currency exchange contracts are derivative instruments whose values depend on, or are derived from, in whole or in part, the value of one or more other assets, in this case, currencies. Derivatives may involve various risks, including the potential inability of the counterparty to fulfill its obligation under the terms of the contract, the potential for an illiquid secondary market (making it difficult for the Fund to sell, including at favorable prices) and the potential for market movements which may expose the Fund to gains or losses in excess of the amount shown in the Statements of Assets and Liabilities.

Columbia Acorn International, Columbia Acorn International Select and Columbia Acorn Emerging Markets Fund each held a put option in 2014, which was acquired through a transaction between the Funds and PT Rajawali Corpora (Indonesia), in connection with the delisting of the shares of Archipelago Resources in 2013. A put option is often held to decrease exposure to an underlying stock. However, in this case, the put option related to the proposed restructuring of Archipelago Resources and provided the Funds with the ability to sell its shares back to PT Rajawali Corpora (Indonesia) at an agreed upon price or to convert the shares held in Archipelago Resources into shares of the newly restructured company based upon the terms of the put option agreement between the Funds and PT Rajawali Corpora (Indonesia). During 2014, the Funds opted to exercise the put option and sell its shares back to PT Rajawali Corpora (Indonesia) with the exercise delivery expected in the first quarter of 2015. The proceeds from the exercising of the put option are included in "Receivable for Investments sold on a delayed delivery basis" in the Statements of Assets and Liabilities.

119

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

For financial reporting purposes, the Funds do not offset derivative assets and derivative liabilities that are subject to netting arrangements in the Statements of Assets and Liabilities.

>Forward foreign currency exchange contracts

Forward foreign currency exchange contracts are agreements between two parties to buy and sell a currency at a set price on a future date. Columbia Acorn International Select utilized forward foreign currency exchange contracts to hedge the currency exposure associated with some or all of the Fund's securities. These instruments may be used for other purposes in future periods. The Fund's use of forward foreign currency exchange contracts was not material to the net assets of the Fund.

The values of forward foreign currency exchange contracts fluctuate with changes in foreign currency exchange rates. Changes in the value of these contracts are recorded as unrealized appreciation or depreciation until the contract is exercised or has expired. The Fund will realize a gain or loss when the forward foreign currency exchange contract is closed or expires.

The use of forward foreign currency exchange contracts does not eliminate fluctuations in the prices of the Fund's portfolio securities. The risks of forward foreign currency exchange contracts include movement in the values of the foreign currencies relative to the U.S. dollar (or other foreign currencies) and the possibility that counterparties will not complete their contractual obligations, which may be in excess of the amount reflected, if any, in the Statements of Assets and Liabilities.

>Offsetting of derivative assets and derivative liabilities

The following table presents the gross and net amount of assets and liabilities of Columbia Acorn International Select, available for offset under netting arrangements as well as any related collateral received or pledged by the Fund as of December 31, 2014:

							Gross Amounts Not Offset in the Statements of Assets and Liabilities
	Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Statements of Assets and Liabilities		Net Amounts of Liabilities Presented in the Statements of Assets and Liabilities		Financial Instruments^(a)		Cash Collateral Pledged		Securities Collateral Pledged		Net Amount^(b)
Liability Derivatives:
Forward Foreign Currency Exchange Contracts	$	97,181	$	—	$	97,181	$	—	$	—	$	—	$	97,181

^(a) Represents the amount of liabilities that could be offset by assets with the same counterparty under master netting or similar agreements that management elects not to offset on the Statements of Assets and Liabilities.

^(b) Represents the net amount due to counterparties in the event of default.

>Effects of derivative transactions in the financial statements

The following tables are intended to provide additional information about the effect of derivatives on the financial statements of Columbia Acorn International, Columbia Acorn International Select and Columbia Acorn Emerging Markets Fund, including: the the fair value of derivatives by risk category and the location of those fair values in the Statements of Assets and Liabilities; and the impact of derivative transactions over the period in the Statements of Operations, including realized gains or losses and unrealized gains or losses. The derivative schedules following the Statements of Investments present additional information regarding derivative instruments outstanding at the end of the period, if any.

Columbia Acorn International

At December 31, 2014, the Fund had no outstanding derivatives.

The following table indicates the effect of derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) in the Statements of Operations for the year ended December 31, 2014:

Change in Unrealized Appreciation (Depreciation)
on Derivatives Recognized in Income

Risk Exposure Category				Options Contracts
Equity risk				$	(2,630,029	)

The following table is a summary of the average outstanding volume by derivative instrument for the year ended December 31, 2014:

Derivative Instrument				Average market value*
Options contracts				$	787,040

* Based on the ending quarterly outstanding amounts for the year ended December 31, 2014.

120

Columbia Acorn International Select

The following table is a summary of the fair value of derivative instruments (not considered to be hedging instruments for accounting disclosure purposes) at December 31, 2014:

	Liability Derivatives
Risk Exposure Category	Statements of Assets and Liabilities Location	Fair Value
Foreign exchange risk	Unrealized depreciation on forward foreign currency exchange contracts	$	97,181

Amount of Realized Gain (Loss) on
Derivatives Recognized in Income

Risk Exposure Category				Forward Foreign Currency Exchange Contracts
Foreign exchange risk				$	469,034

Change in Unrealized Appreciation (Depreciation)
on Derivatives Recognized in Income

Risk Exposure Category	Forward Foreign Currency Exchange Contracts			Options Contracts			Total
Equity risk	$	—		$	(985,539	)	$	(985,539	)
Foreign exchange risk		(162,999	)		—			(162,999	)
Total	$	(162,999	)	$	(985,539	)	$	(1,148,538	)

The following table is a summary of the average outstanding volume by derivative instrument for the year ended December 31, 2014:

Derivative Instrument				Average market value*
Options contracts				$	294,924

Derivative Instrument				Average unrealized appreciation*				Average unrealized depreciation*
Forward foreign currency exchange contracts				$	54,284			$	(89,471	)

* Based on the ending quarterly outstanding amounts for the year ended December 31, 2014.

Columbia Acorn Emerging Markets Fund

At December 31, 2014, the Fund had no outstanding derivatives.

Change in Unrealized Appreciation (Depreciation) on Derivatives Recognized in Income

Risk Exposure Category				Options Contracts
Equity risk				$	(131,808	)

The following table is a summary of the average outstanding volume by derivative instrument for the year ended December 31, 2014:

Derivative Instrument				Average market value*
Options contracts				$	39,444

* Based on the ending quarterly outstanding amounts for the year ended December 31, 2014.

>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 may receive distributions from holdings in exchange-traded funds (ETFs), other regulated investment companies (RICs), and real estate investment trusts (REITs), which report information on the character of their distributions annually. These distributions are allocated to dividend income, capital gain and return of capital based on actual information reported. To the extent actual information has not yet been reported by the REITs, estimates for return of capital may be made by the Funds' management. Return of capital is recorded as a reduction of the cost basis of securities held. If the Funds no longer own the applicable securities, return of capital is recorded as a realized gain. Management's estimates are subsequently adjusted when the actual character of the distributions is disclosed by the REITs, which could result in a proportionate change in return of capital to shareholders. No estimates are made for ETFs and RICs.

>Fund share valuation

Fund shares are sold and redeemed on a daily 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 distribution

121

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

and service fees and transfer agent 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.

>Securities lending

Each Fund, except Columbia Thermostat 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. The Funds retain the benefits of owning the securities, including the economic equivalent of dividends or interest generated by the security. The Funds also receive a fee for the loan. The Funds have 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 a Fund

and any additional required collateral is delivered to the Fund on the next business day. The Funds have elected to invest the cash collateral in the Dreyfus Government Cash Management Fund. The income earned from the securities lending program is paid to each Fund, net of any fees remitted to Goldman Sachs Agency Lending, the Funds' lending agent, and net of any borrower rebates. The Investment Manager does not retain any fees earned by the lending program. Generally, in the event of borrower default, a Fund has the right to use the collateral to offset any losses incurred. In the event a 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 Funds bear the risk of loss with respect to the investment of collateral. The net securities lending income earned as of December 31, 2014 by each Fund is included in the Statements of Operations.

>Offsetting of Financial Assets

The following table presents each Fund's gross and net amount of assets available for offset under a securities lending agreement as well as the related collateral received by the Fund as of December 31, 2014:

							Gross Amounts Not Offset in the Statements of Assets and Liabilities
	Gross Amounts of Recognized Assets		Gross Amounts Offset in the Statements of Assets and Liabilities		Net Amounts of Assets Presented in the Statements of Assets and Liabilities		Financial Instruments^(a)		Cash Collateral Received		Securities Collateral Received		Net Amount^(b)
Securities Loaned
Columbia Acorn Fund	$	517,888,630	$	—	$	517,888,630	$	—	$	517,888,630	$	—	$	—
Columbia Acorn International		101,872,493		—		101,872,493		—		101,872,493		—		—
Columbia Acorn USA		76,216,239		—		76,216,239		—		76,216,239		—		—
Columbia Acorn International Select		5,229,212		—		5,229,212		—		5,229,212		—		—
Columbia Acorn Select		25,021,001		—		25,021,001		—		25,021,001		—		—
Columbia Acorn Emerging Markets Fund		3,111,617		—		3,111,617		—		3,111,617		—		—
Columbia Acorn European Fund		899,714		—		899,714		—		899,714		—		—

^(a) Represents the amount of assets that could be offset by liabilities with the same counterparty under master netting or similar agreements that management elects not to offset on the Statements of Assets and Liabilities.

^(b) Represents the net amount due from counterparties in the event of default.

>Federal income taxes

It is each Fund's policy to comply with the provisions of the Internal Revenue Code available to regulated investment companies and, in the manner provided therein, distribute substantially 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. The Funds accrue for such foreign taxes on realized and unrealized gains at the appropriate rate for each jurisdiction. The amount, if any, is disclosed as a liability on the Statements of Assets and Liabilities.

>Distributions to shareholders

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

122

>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 remote.

>Recent Accounting Pronouncement

Transfers and Servicing (Topic 860), Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures

In June 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2014-11, Transfers and Servicing (Topic 860), Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures. ASU No. 2014-11 changes the accounting for transactions accounted for as secured borrowings and expands disclosure requirements related to securities lending and similar transactions. The disclosure requirements are effective for interim and annual periods beginning after December 15, 2014. At this time, management is evaluating the implications of this guidance and the impact it will have on the financial statement amounts and footnote disclosures, if any.

3. Federal Tax Information

The timing and character of income and capital gain distributions are determined in accordance with income tax regulations, which may differ from GAAP. Reclassifications are made

to the Funds' capital accounts for permanent tax differences to reflect income and gains available for distribution (or available capital loss carryforwards) under income tax regulations.

For the year ended December 31, 2014, permanent book and tax basis differences resulting primarily from foreign currency transactions, passive foreign investment company (PFIC) holdings, re-characterization of distributions from investments, net operating loss reclassification, distribution reclassifications and earnings and profits distributed to shareholders on the redemption of shares, were identified and reclassified among the components of each Fund's net assets as follows:

	Undistributed/ (Overdistributed) or Accumulated Net Investment Income (Loss)			Accumulated Net Realized Gain/(Loss)			Paid-In Capital
Columbia Acorn Fund	$	37,878,939		$	(391,692,152	)	$	353,813,213
Columbia Acorn International		48,897,239			(48,897,240	)		1
Columbia Acorn USA		6,156,863			273,193			(6,430,056	)
Columbia Acorn International Select		3,677,227			(3,677,227	)		—
Columbia Acorn Select		3,796,729			124,894			(3,921,623	)
Columbia Thermostat Fund		230,370			(3,701,459	)		3,471,089
Columbia Acorn Emerging Markets Fund		(38,956	)		38,957			(1	)
Columbia Acorn European Fund		(22,900	)		22,900			—

Net investment income (loss) and net realized gains (losses), as disclosed on the Statements of Operations, and net assets were not affected by this reclassification.

The tax character of distributions paid during the years ended December 31, 2014 and December 31, 2013 was as follows:

	December 31, 2014				December 31, 2013
Fund	Ordinary Income*		Long-Term Capital Gains		Ordinary Income*		Long-Term Capital Gains
Columbia Acorn Fund	$	—	$	2,682,706,755	$	21,340,532	$	1,308,033,846
Columbia Acorn International		116,690,475		413,210,257		198,930,778		330,008,029
Columbia Acorn USA		—		246,242,710		—		141,393,055
Columbia Acorn International Select		2,302,638		32,121,809		5,084,134		25,050,362
Columbia Acorn Select		—		143,373,013		3,241,093		198,890,427
Columbia Thermostat Fund		29,624,764		9,456,050		32,251,737		52,560,790
Columbia Acorn Emerging Markets Fund		3,506,088		—		2,558,438		—
Columbia Acorn European Fund		353,305		90,617		41,172		24,867

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

123

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

As of December 31, 2014, the components of distributable earnings on a tax basis were as follows:

Fund	Undistributed Ordinary Income		Undistributed Long-Term Capital Gains		Capital Loss Carryforwards			Net Unrealized Appreciation (Depreciation)*
Columbia Acorn Fund	$	—	$	606,933,438	$	—		$	7,081,725,961
Columbia Acorn International		—		69,311,634		(32,978,592	)		1,415,663,530
Columbia Acorn USA		—		33,730,542		—			650,557,477
Columbia Acorn International Select		896,977		—		—			13,352,991
Columbia Acorn Select		—		48,428,589		—			206,403,152
Columbia Thermostat Fund		10,966,888		13,043,172		—			32,679,389
Columbia Acorn Emerging Markets Fund		—		—		(14,671,234	)		15,058,101
Columbia Acorn European Fund		200,929		—		(2,338,404	)		45,678

* The differences between book-basis and tax-basis net unrealized appreciation (depreciation) are primarily due to deferral of losses from wash sales and PFIC adjustments.

The following capital loss carryforwards, determined as of December 31, 2014, 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
	2015		2016		No Expiration Short-Term		Total
Columbia Acorn International	$	2,521,892	$	30,456,700	$	—	$	32,978,592
Columbia Acorn Emerging Markets Fund		—		—		14,671,234		14,671,234
Columbia Acorn European Fund		—		—		2,338,404		2,338,404

The value of capital loss carryforwards that were utilized, expired and permanently lost for the Funds during the year ended December 31, 2014, were as follows:

				Utilized				Expired				Lost
Columbia Acorn International				$	18,996,063			$	—			$	—

Under current tax rules, Regulated Investment Companies can elect to treat certain late-year ordinary losses incurred and post-October capital losses (capital losses realized after October 31) as arising on the first day of the following taxable year. As of December 31, 2014, the Funds will elect to treat the following late-year ordinary losses and post-October capital losses as arising on January 1, 2015:

Fund	Late-Year Ordinary Losses		Post-October Capital Losses
Columbia Acorn International Select	$	—	$	8,767,586
Columbia Acorn Emerging Markets Fund		533,398		—

Management of the Funds has concluded that there are no significant uncertain tax positions in any Fund that would require recognition in the financial statements. However, management's conclusion may be subject to review and adjustment at a later date based on factors including, but not limited to, new tax laws, regulations, and administrative interpretations (including relevant court decisions). Generally, the Funds' federal tax returns for the prior three fiscal years remain subject to examination by the Internal Revenue Service.

4. Transactions with Affiliates

CWAM is a wholly-owned subsidiary of Columbia Management Investment Advisers, LLC (Columbia Management), which is a

wholly-owned subsidiary of Ameriprise Financial, Inc. (Ameriprise Financial). CWAM furnishes continuing investment supervision to the Funds and is responsible for the overall management of the Funds' business affairs.

CWAM receives a monthly advisory fee based on each Fund's average daily net assets at the following annual rates:

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	%

124

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	%

Columbia Acorn Emerging Markets Fund

Average Daily Net Assets	Annual Fee Rate
Up to $100 million		1.25	%
$100 million to $500 million		1.00	%
$500 million and over		0.80	%

Columbia Acorn European Fund

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	%

For the year ended December 31, 2014, the effective investment advisory fee rates were as follows:

Fund
Columbia Acorn Fund	0.64	%
Columbia Acorn International	0.75	%
Columbia Acorn USA	0.86	%
Columbia Acorn International Select	0.94	%
Columbia Acorn Select	0.85	%
Columbia Thermostat Fund	0.10	%
Columbia Acorn Emerging Markets Fund	1.04	%
Columbia Acorn European Fund	1.19	%

>Expense limits

Columbia Management Investment Services Corp. (CMIS), a wholly owned subsidiary of Ameriprise Financial, has voluntarily agreed to waive a portion of the total annual Fund operating expenses attributable to transfer agency fees incurred by Class A, Class B and Class C shares of Columbia Acorn International such that the Fund's total annual Fund operating expenses will be reduced by 0.04%, 0.03% and 0.02% for Class A, Class B and Class C shares of the Fund, respectively.

Effective May 1, 2014, CWAM has voluntarily agreed to reimburse expenses so that the Funds' ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with each Fund's investments in other investment companies, if any) after giving effect to any balance credits or overdraft charges from the Funds' custodian, do not exceed annually the average daily net assets of each class as follows:

Fund	Class A			Class B			Class C			Class I			Class R4			Class R5			Class Y			Class Z
Columbia Acorn International Select		1.70	%		2.20	%		2.45	%		1.37	%		1.45	%		1.42	%		1.37	%		1.45	%
Columbia Acorn Select		1.60	%		2.10	%		2.35	%		1.22	%		1.35	%		1.27	%		1.22	%		1.35	%

These arrangements may be modified or terminated by either the Funds or CWAM on 30 days notice.

Through April 30, 2014, CWAM voluntarily reimbursed expenses so that the Funds' ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with each Fund's investments in other investment companies, if any) after giving effect to any balance credits or overdraft charges from the Funds' custodian, did not exceed annually the average daily net assets of each class as follows:

Fund	Class A			Class B			Class C			Class I			Class R4			Class R5			Class Y			Class Z
Columbia Acorn International Select		1.70	%		2.20	%		2.45	%		1.31	%		1.45	%		1.36	%		1.31	%		1.45	%
Columbia Acorn Select		1.60	%		2.10	%		2.35	%		1.23	%		1.35	%		1.28	%		1.23	%		1.35	%

Effective May 1, 2014, CWAM has contractually agreed to waive fees and/or reimburse expenses through April 30, 2015, so that the Funds' ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with each Fund's investments in other investment companies, if any, and in the

125

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

case of Columbia Thermostat Fund its underlying portfolio funds), do not exceed annually the average daily net assets of each class as follows:

Fund	Class A			Class B			Class C			Class I			Class R4			Class R5			Class Y			Class Z
Columbia Thermostat Fund		0.50	%		1.00	%		1.25	%		—	%		0.25	%		0.23	%		0.18	%		0.25	%
Columbia Acorn Emerging Markets Fund		1.85	%		—	%		2.60	%		1.46	%		1.60	%		1.51	%		1.46	%		1.60	%
Columbia Acorn European Fund		1.75	%		—	%		2.50	%		1.47	%		1.50	%*		1.52	%		—	%		1.50	%

* Effective June 25, 2014 (the commencement of operations of Columbia Acorn European Fund Class R4 shares) through April 30, 2015.

There is no guarantee that these agreements will continue thereafter.

Through April 30, 2014, CWAM contractually waived fees and/or reimburse expenses so that the Funds' ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with each Fund's investments in other investment companies, if any, and in the case of Columbia Thermostat Fund its underlying portfolio funds), did not exceed annually the average daily net assets of each class as follows:

Fund	Class A			Class B			Class C			Class I			Class R4			Class R5			Class Y			Class Z
Columbia Thermostat Fund		0.50	%		1.00	%		1.25	%		—	%		0.25	%		0.23	%		0.18	%		0.25	%
Columbia Acorn Emerging Markets Fund		1.85	%		—	%		2.60	%		1.54	%		1.60	%		1.59	%		1.54	%		1.60	%
Columbia Acorn European Fund		1.75	%		—	%		2.50	%		1.46	%		—	%		1.51	%		—	%		1.50	%

Expenses reimbursed by CWAM and its affiliates for the year ended December 31, 2014, were as follows:

Fund	Expenses Reimbursed
Columbia Acorn International	$	452,267
Columbia Acorn Select		854
Columbia Thermostat Fund		135,531
Columbia Acorn European Fund		147,638

CWAM is contractually entitled to recoup from each of Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund any fees waived and/or expenses reimbursed with respect to any share class offered by Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund for a one year period following the date of such fee waiver and/or reimbursement, if such recovery does not cause the ordinary operating expenses of the Fund (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with the Fund's investment in other investment companies, if any) to exceed the annual rates set forth above, or to exceed such annual rate as may be in place at the time of the recoupment, whichever is less.

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 year ended December 31, 2014, the effective administration fee rate was 0.04% of each Fund's average daily net assets. CWAM has delegated to Columbia Management responsibility to provide certain sub-administrative services to the Funds.

CMID, a wholly owned subsidiary of Ameriprise Financial, is the distributor of the Funds.

Sales charges, including front-end and CDSCs, received by the Distributor for distributing each Fund's shares for the year ended December 31, 2014 are as follows:

	Underwriting Discounts		CDSCs
(Unaudited)	Class A		Class A		Class B		Class C
Columbia Acorn Fund	$	1,435,758	$	12,592	$	438	$	31,848
Columbia Acorn International		592,622		6,544		1,004		7,646
Columbia Acorn USA		85,622		1,772		—		2,679
Columbia Acorn International Select		49,250		1		—		865
Columbia Acorn Select		50,998		21		194		1,816
Columbia Thermostat Fund		1,181,699		21,521		53		74,964
Columbia Acorn Emerging Markets Fund		314,720		5,137		—		8,322
Columbia Acorn European Fund		81,450		30		—		1,175

Each Fund has adopted a distribution and service plan which requires it to pay CMID 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%, 0.75% and 0.50%, annually, of the average daily net assets attributable to Class B, Class C and Class R

126

shares, respectively. CMID receives no compensation with respect to Class R4, Class R5, Class Y and Class Z shares.

CMIS is the transfer agent of the Funds. CMIS receives monthly account-based service fees based on the number of open Fund accounts. Each Fund pays CMIS a monthly fee at the annual rate of $20.00 per open account. Subject to certain limitations, the Funds reimburse payments made by CMIS to financial intermediaries for the shareholder services that the intermediaries

provide, in amounts that vary by share class and with the type of intermediary and type of shareholder services provided.

The Transfer Agent also receives compensation from fees for various shareholder services and reimbursements for certain out-of-pocket fees. Total transfer agent fees for Class R5 shares are subject to an annual limitation of not more than 0.05% of the average daily net assets attributable to Class R5 shares. Class I shares and Class Y shares do not pay transfer agency fees.

For the year ended December 31, 2014, the Funds' effective transfer agent fee rates as a percentage of average daily net assets of each class were as follows:

Fund	Class A			Class B			Class C			Class R			Class R4			Class R5			Class Z
Columbia Acorn Fund		0.12	%		0.30	%		0.07	%		—	%		0.13	%		0.05	%		0.08	%
Columbia Acorn International		0.16	%		0.40	%		0.13	%		0.27	%		0.18	%		0.05	%		0.08	%
Columbia Acorn USA		0.15	%		0.57	%		0.06	%		—	%		0.13	%		0.05	%		0.14	%
Columbia Acorn International Select		0.12	%		0.27	%		0.14	%		—	%		0.11	%		0.05	%		0.08	%
Columbia Acorn Select		0.12	%		0.45	%		0.09	%		—	%		0.17	%		0.05	%		0.09	%
Columbia Thermostat Fund		0.07	%		0.22	%		0.07	%		—	%		0.07	%		0.05	%		0.06	%
Columbia Acorn Emerging Markets Fund		0.11	%		—	%		0.12	%		—	%		0.07	%		0.05	%		0.12	%
Columbia Acorn European Fund		0.11	%		—	%		0.13	%		—	%		0.12	%		0.05	%		0.10	%

Columbia Acorn International and certain other associated investment companies, have severally, but not jointly, guaranteed the performance and observance of all the terms and conditions of a lease entered into by Seligman Data Corp. (SDC), the former transfer agent to certain associated investment companies, including the payment of rent by SDC (the Guaranty). The lease and the Guaranty expire in January 2019. At December 31, 2014, Columbia Acorn International's total potential future obligation over the life of the Guaranty is $83,362. The liability remaining at December 31, 2014 for non-recurring charges associated with the lease amounted to $53,685 and is included within the "Payable for Other liabilities" in the Statements of Assets and Liabilities.

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 has appointed a Chief Compliance Officer of 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.

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 may 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 as specified by the trustee. Benefits under the deferred compensation plan are payable in accordance with the plan.

An affiliated person of a Fund may include any company in which a Fund owns five percent or more of its outstanding voting shares during the year. On December 31, 2014, Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn Select and Columbia Thermostat Fund each held five percent or more of the outstanding voting securities of one or more companies or a company which is under common ownership or control with the Funds. Details of investments in those affiliated companies are presented in the Notes to Statement of Investments of each Fund listed above.

For the year ended December 31, 2014, the Funds engaged in purchase and sales transactions with funds that have a common investment manager (or affiliated investment managers), common directors/trustees, and/or common officers. Those transactions complied with Rule 17a-7 under the Investment Company Act of 1940 and totaled as follows:

	Purchases		Sales
Columbia Acorn Fund	$	—	$	42,246,098
Columbia Acorn International		39,818,858		—
Columbia Acorn International Select		—		2,898,140
Columbia Acorn European Fund		59,702		970,001

127

Columbia Acorn Family of Funds

Notes to Financial Statements, continued

5. Borrowing Arrangements

During the year ended December 31, 2014, the Trust participated in a credit facility with JPMorgan Chase Bank, N.A., along with Wanger Advisors Trust, another trust managed by CWAM, in the amount of $150 million. The credit facility 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 Federal Funds Rate plus 1.00%. In addition, a commitment fee of 0.08% 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 disclosed as a part of "Other expenses" in the Statements of Operations. The Trust expects to renew this line of credit for one year durations each July at then current market rates and terms.

No amounts were borrowed for the benefit of a Fund under the line of credit during the year ended December 31, 2014.

6. Investment Transactions

The aggregate cost of purchases and proceeds from sales, other than short-term obligations, for the year ended December 31, 2014, were:

	Purchases		Proceeds from Sales
Columbia Acorn Fund	$	3,275,347,007	$	8,592,258,057
Columbia Acorn International		2,237,161,643		2,573,022,536
Columbia Acorn USA		189,636,474		622,182,315
Columbia Acorn International Select		183,138,204		273,542,036
Columbia Acorn Select		131,244,205		341,575,769
Columbia Thermostat Fund		1,225,640,896		1,327,359,510
Columbia Acorn Emerging Markets Fund		297,006,975		220,140,785
Columbia Acorn European Fund		50,568,798		34,379,689

The amount of purchase and sales activity impacts the portfolio turnover rate reported in the Financial Highlights.

7. Shareholder Concentration

At December 31, 2014, the table below details the affiliated and significant unaffiliated shareholder account ownership of outstanding shares of each Fund. The Funds have no knowledge about whether any portion of these unaffiliated shares were owned beneficially. Subscription and redemption activity of these accounts may have a significant effect on the operations of the Funds.

Fund	Number of unaffiliated accounts		Percentage of shares outstanding held – unaffiliated			Percentage of shares outstanding held – affiliated
Columbia Acorn Fund		1		15.3	%		—	%
Columbia Acorn International		2		27.6	%		—	%
Columbia Acorn USA		3		51.1	%		—	%
Columbia Acorn International Select		2		38.8	%		10.9	%
Columbia Acorn Select		2		34.2	%		12.5	%
Columbia Thermostat Fund		1		20.6	%		23.9	%
Columbia Acorn Emerging Markets Fund		3		45.7	%		23.3	%
Columbia Acorn European Fund		—		—	%		57.8	%

8. Subsequent Events

Management has evaluated the events and transactions that have occurred through the date the financial statements were issued and noted no items requiring adjustment of the financial statements or additional disclosure.

9. Information Regarding Pending and Settled Legal Proceedings

Ameriprise Financial and certain of its affiliates have historically been involved in a number of legal, arbitration and regulatory proceedings, including routine litigation, class actions, and governmental actions, concerning matters arising in connection with the conduct of their business activities. Ameriprise Financial believes that the Funds are not currently the subject of, and that neither Ameriprise Financial nor any of its affiliates are the subject of, any pending legal, arbitration or regulatory proceedings that are likely to have a material adverse effect on the Funds or the ability of Ameriprise Financial or its affiliates to perform under their contracts with the Funds. Ameriprise Financial is required to make quarterly (10-Q), annual (10-K) and, as necessary, 8-K filings with the Securities and Exchange Commission on legal and regulatory matters that relate to Ameriprise Financial and its affiliates. Copies of these filings may be obtained by accessing the SEC website at www.sec.gov.

There can be no assurance that these matters, or the adverse publicity associated with them, will not result in increased fund redemptions, reduced sale of fund shares or other adverse consequences to the Funds. Further, although we believe proceedings are not likely to have a material adverse effect on the Funds or the ability of Ameriprise Financial or its affiliates to perform under their contracts with the Funds, these proceedings are subject to uncertainties and, as such, we are unable to estimate the possible loss or range of loss that may result. An adverse outcome in one or more of these proceedings could result in adverse judgments, settlements, fines, penalties or other relief that could have a material adverse effect on the consolidated financial condition or results of operations of Ameriprise Financial.

128

Report of Independent Registered Public Accounting Firm

To the Board of Trustees and Shareholders of
Columbia Acorn Trust:

In our opinion, the accompanying statements of assets and liabilities, including the statements of investments, and the related statements of operations and of changes in net assets and the financial highlights present fairly, in all material respects, the financial position of Columbia Acorn Fund, Columbia Acorn International, Columbia Acorn USA, Columbia Acorn International Select, Columbia Acorn Select, Columbia Thermostat Fund, Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund (each a series of the Columbia Acorn Trust, hereinafter referred to as the "Funds") at December 31, 2014, the results of each of their operations for the year then ended, the changes in each of their net assets for each of the two years in the period then ended and the financial highlights for each of the periods presented, in conformity with accounting principles generally accepted in the United States of America. These financial statements and financial highlights (hereafter referred to as "financial statements")

are the responsibility of the Funds' management; our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these financial statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits, which included confirmation of securities at December 31, 2014 by correspondence with the custodian and brokers, provide a reasonable basis for our opinion.

PricewaterhouseCoopers LLP
Chicago, Illinois
February 19, 2015

129

Columbia Acorn Family of Funds

Federal Income Tax Information (Unaudited)

The Funds hereby designate the following tax attributes for the fiscal year ended December 31, 2014.

	Qualified Dividend Income			Dividends Received Deduction			Capital Gain Dividend		Foreign Taxes Paid		Foreign Taxes Paid Per Share		Foreign Source Income		Foreign Source Income Per Share
Columbia Acorn Fund		—	%		—	%	$	3,388,331,689	$	—	$	—	$	—	$	—
Columbia Acorn International		98.68	%		—	%	$	410,719,781	$	17,276,766	$	0.09	$	185,883,142	$	1.00
Columbia Acorn USA		—	%		—	%	$	270,758,416	$	—	$	—	$	—	$	—
Columbia Acorn International Select		100.00	%		3.92	%	$	32,336,116	$	639,342	$	0.06	$	9,200,048	$	0.81
Columbia Acorn Select		—	%		—	%	$	159,598,820	$	—	$	—	$	—	$	—
Columbia Thermostat Fund		6.08	%		4.64	%	$	20,250,975	$	51,990	$	—	$	373,276	$	—
Columbia Acorn Emerging Markets Fund		100.00	%		—	%	$	—	$	1,078,712	$	0.03	$	11,153,698	$	0.29
Columbia Acorn European Fund		100.00	%		0.69	%	$	—	$	95,533	$	0.04	$	1,289,056	$	0.50

The following Funds hereby designate additional tax attributes for the fiscal year ended December 31, 2013.

	Foreign Taxes Paid		Foreign Taxes Paid Per Share
Columbia Acorn International Select	$	168,503	$	0.01
Columbia Thermostat Fund	$	20,604	$	—
Columbia Acorn European Fund	$	812	$	—

Qualified Dividend Income. For taxable, non-corporate shareholders, the percentage of ordinary income distributed during the fiscal year that represents qualified dividend income subject to reduced tax rates.

Dividends Received Deduction. The percentage of ordinary income distributed during the fiscal year that qualifies for the corporate dividends received deduction.

Capital Gain Dividend. The Fund designates as a capital gain dividend the amount reflected above, or if subsequently determined to be different, the net capital gain of such fiscal period.

Foreign Taxes. The Fund makes the election to pass through to shareholders the foreign taxes paid. Eligible shareholders may claim a foreign tax credit. These taxes, and the corresponding foreign source income, are provided.

130

Board of Trustees and Management of
Columbia Acorn Family of Funds

Each trustee may serve a term of unlimited duration. The Trust's By-laws generally require that a trustee retire at the end of the calendar year in which the trustee attains the age of 75 years. The trustees appoint their own successors, provided that at least two-thirds of the trustees, after such appointment, have been elected by shareholders. Shareholders may remove a trustee, with or without cause, upon the vote of two-thirds of the Trust's outstanding shares at any meeting called for that purpose. A trustee may be removed, with or without cause, upon the vote of a majority of the trustees. The names of the trustees and officers of the Trust, the date each was first elected or appointed to office, their principal business occupations during at least the last five years, the number of portfolios in the fund complex they oversee, and other directorships they hold, are shown below. Each trustee serves in such capacity for each of the eight series of Columbia Acorn Trust and for each of the four series of Wanger Advisors Trust.

The address for the trustees and officers of the Trust is Columbia Wanger Asset Management, LLC, 227 West Monroe Street, Suite 3000, Chicago, Illinois 60606. The Funds' Statement of Additional Information includes additional information about the Funds' trustees and officers. You may obtain a free copy of the Statement of Additional Information by writing or calling toll-free:

Columbia Wanger Asset Management, LLC
Shareholder Services Group
227 W. Monroe, Suite 3000
Chicago IL 60606
1-800-922-6769

Name, Position
Held with
Columbia Acorn
Trust and Age at
December 31, 2014

Year First
Appointed or
Elected to a
Board in the
Columbia
Funds
Complex*

Principal Occupation(s)
during the Past Five Years

Number of
Funds in the
Columbia
Funds
Complex
Overseen

Other
Directorships
in addition to
Columbia Acorn Trust

Trustees who are not interested persons of Columbia Acorn Trust:⁽¹⁾

Laura M. Born, 49,
Trustee and Chair

2007

Adjunct Associate Professor of Finance, University of Chicago Booth School of Business; Managing Director – Investment Banking, J.P. Morgan Chase & Co. (broker-dealer), 2002-2007.

Wanger Advisors Trust.

Maureen M. Culhane, 66,
Trustee

2007

Retired. Formerly, Vice President, Goldman Sachs Asset Management, L.P. (investment adviser), 2005-2007; Vice President (Consultant) – Strategic Relationship Management, Goldman, Sachs & Co., 1999-2005.

Wanger Advisors Trust.

Margaret M. Eisen, 61,
Trustee

2002

Chief Investment Officer, EAM International LLC (corporate finance and asset management), 2003-2013; Managing Director, CFA Institute, 2005-2008.

Wanger Advisors Trust; Burnham Investors Trust.

Thomas M. Goldstein, 55,
Trustee

2014

Retired. Formerly, Chief Financial Officer, Allstate Protection Division, 2011-2014; Founding Partner, The GRG Group LLC, 2009-2011; Managing Director and Chief Financial Officer, Madison Dearborn Partners, 2007-2009.

Wanger Advisors Trust; Federal Home Loan Bank – Chicago; Federal Home Loan Mortgage Corporation.

John C. Heaton, 55,
Trustee

2010

Deputy Dean for Faculty, University of Chicago Booth School of Business; Joseph L. Gidwitz Professor of Finance, University of Chicago Booth School of Business since 2000.

Wanger Advisors Trust.

Steven N. Kaplan, 55,
Trustee and Vice Chair

1999

Neubauer Family Distinguished Service Professor of Entrepreneurship and Finance, University of Chicago Booth School of Business; faculty member of the University of Chicago Booth School of Business since 1988.

Wanger Advisors Trust; Accretive Health, Inc. (healthcare management services provider); Morningstar, Inc. (provider of independent investment research).

David J. Rudis, 61,
Trustee

2010

Retired. Formerly, National Checking and Debit Executive, and Illinois President, Bank of America, 2007-2009; President, Consumer Banking Group, LaSalle National Bank, 2004-2007.

Wanger Advisors Trust.

David B. Small, 58,
Trustee⁽²⁾

2010

Managing Director, Grosvenor Capital Management, L.P. (investment adviser) since 1994; Adjunct Associate Professor of Finance, University of Chicago Booth School of Business.

Wanger Advisors Trust.

131

Name, Position
Held with
Columbia Acorn
Trust and Age at
December 31, 2014

Year First
Appointed or
Elected to a
Board in the
Columbia
Funds
Complex*

Principal Occupation(s)
during the Past Five Years

Number of
Funds in the
Columbia
Funds
Complex
Overseen

Other
Directorships
in addition to
Columbia Acorn Trust

Trustees who are interested persons of Columbia Acorn Trust:

Charles P. McQuaid, 61,
Trustee and Vice President⁽³⁾

1992

Portfolio manager and/or analyst, CWAM or its predecessors since 1978; Vice President of Columbia Acorn Trust and Wanger Advisors Trust since April 2014; formerly, President and Chief Investment Officer, CWAM or its predecessors, October 2003-March 2014, and President of Columbia Acorn Trust and Wanger Advisors Trust, October 2003-March 2014.

Wanger Advisors Trust.

Ralph Wanger, 80,
Trustee Emeritus⁽⁴⁾

1970

Founder, CWAM. Formerly, President, Chief Investment Officer and portfolio manager, CWAM or its predecessors, July 1992 – September 2003; Director, Wanger Investment Company PLC; Consultant to CWAM or its predecessors, September 2003 – September 2005.

Wanger Advisors Trust.

Officers of Columbia Acorn Trust:

Robert A. Chalupnik, 49,
Vice President

2011

Portfolio manager and/or analyst, CWAM or its predecessors since 2000; Vice President Columbia Acorn Trust and Wanger Advisors Trust since 2011.

N/A

Michael G. Clarke, 45,
Assistant Treasurer

2004

Vice President – Mutual Fund Treasurer, Columbia Management Investment Advisers, LLC since May 2010; Managing Director of Fund Administration, Columbia Management Advisors, LLC, September 2004-April 2010; Senior officer, Columbia Funds and affiliated funds since 2002.

N/A

Joseph F. DiMaria, 46,
Assistant Treasurer

2010

Vice President – Mutual Fund Administration, Columbia Management Investment Advisers, LLC since May 2010; Director of Fund Administration, Columbia Management Advisors, LLC, January 2006-April 2010.

N/A

William J. Doyle, 50,
Vice President

2014

Portfolio manager and/or analyst, CWAM or its predecessors since 2006; Vice President, Columbia Acorn Trust and Wanger Advisors Trust since 2014.

N/A

P. Zachary Egan, 46,
President

2014

President and International Chief Investment Officer, CWAM since April 2014; portfolio manager and/or analyst, CWAM or its predecessors since 1999; formerly, Director of International Research, CWAM December 2004-March 2014, and Vice President, Columbia Acorn Trust, 2003-2014, and Wanger Advisors Trust, 2007-2014.

N/A

David L. Frank, 51,
Vice President

2014

Portfolio manager and/or analyst, CWAM or its predecessors since 2002; Vice President, Columbia Acorn Trust and Wanger Advisors Trust since 2014.

N/A

Fritz Kaegi, 43,
Vice President

2011

Portfolio manager and/or analyst, CWAM or its predecessors since 2004; Vice President, Columbia Acorn Trust and Wanger Advisors Trust since 2011.

N/A

John M. Kunka, 44,
Treasurer

2006

Treasurer and Principal Accounting and Financial Officer, Columbia Acorn Trust and Wanger Advisors Trust since 2014; Director of Accounting and Operations, CWAM since May 2006; formerly, Assistant Treasurer, Columbia Acorn Trust and Wanger Advisors Trust 2006-2014.

N/A

132

Name, Position
Held with
Columbia Acorn
Trust and Age at
December 31, 2014

Year First
Appointed or
Elected to a
Board in the
Columbia
Funds
Complex*

Principal Occupation(s)
during the Past Five Years

Number of
Funds in the
Columbia
Funds
Complex
Overseen

Other
Directorships
in addition to
Columbia Acorn Trust

Officers of Columbia Acorn Trust: (continued)

Stephen Kusmierczak, 47,
Vice President

2011

Portfolio manager and/or analyst, CWAM or its predecessors since 2001; Vice President, Columbia Acorn Trust and Wanger Advisors Trust since 2011.

N/A

Joseph C. LaPalm, 45,
Vice President

2006

Chief Compliance Officer, CWAM since 2005.

N/A

Charles P. McQuaid, 61,
Vice President

1992

N/A

Louis J. Mendes III, 50,
Vice President

2003

Portfolio manager and/or analyst, CWAM or its predecessors since 2001; Vice President, Columbia Acorn Trust since 2003 and Wanger Advisors Trust since 2005.

N/A

Robert A. Mohn, 53,
Vice President

1997

Domestic Chief Investment Officer, CWAM since April 2014; Vice President, Columbia Acorn Trust and Wanger Advisors Trust since 1997; portfolio manager and/or analyst, CWAM or its predecessors since 1992; formerly, Director of Domestic Research, CWAM or its predecessors, March 2004-March 2014. Mr. Mohn served as Principal Executive Officer of the Funds during Mr. McQuaid's sabbatical from January 14 through March 31, 2011.

N/A

Christopher J. Olson, 50,
Vice President

2001

Portfolio manager and/or analyst, CWAM or its predecessors since January 2001; Vice President, Columbia Acorn Trust and Wanger Advisors Trust since 2001.

N/A

Christopher O. Petersen, 44,
Assistant Secretary

2010

Vice President and Lead Chief Counsel, Ameriprise Financial, Inc. since January 2015 (previously, Vice President and Chief Counsel, January 2010-December 2014 and Vice President and Group Counsel or Counsel, 2004-2010); officer, Columbia Funds and affiliated funds since 2007.

N/A

133

Name, Position
Held with
Columbia Acorn
Trust and Age at
December 31, 2014

Year First
Appointed or
Elected to a
Board in the
Columbia
Funds
Complex*

Principal Occupation(s)
during the Past Five Years

Number of
Funds in the
Columbia
Funds
Complex
Overseen

Other
Directorships
in addition to
Columbia Acorn Trust

Officers of Columbia Acorn Trust: (continued)

Scott R. Plummer, 55,
Assistant Secretary

2010

Senior Vice President, Assistant General Counsel and Head of Global Asset Management, Ameriprise Financial, Inc. since February 2014 (previously, Senior Vice President and Lead Chief Counsel – Asset Management, January 2012-February 2014; Vice President and Lead Chief Counsel – Asset Management, 2010-2012; and Vice President and Chief Counsel – Asset Management, 2005-2010); Senior Vice President and Assistant Secretary, Columbia Management Investment Advisers, LLC since June 2005 (previously, Chief Legal Officer, Columbia Management Investment Advisers, LLC, June 2005-January 2015); Vice President, Chief Counsel and Assistant Secretary, Columbia Management Investment Distributors, Inc. since 2008; Vice President, General Counsel and Secretary, Ameriprise Certificate Company since 2005; Chief Counsel, RiverSource Distributors, Inc. since 2006; senior officer of Columbia Funds and affiliated funds 2006-2014.

N/A

Robert P. Scales, 62,
Chief Compliance Officer, Chief Legal Officer, Senior Vice President and General Counsel

2004

Chief Compliance Officer, Chief Legal Officer, Senior Vice President and General Counsel, Columbia Acorn Trust and Wanger Advisors Trust since 2004.

N/A

Andreas Waldburg-Wolfegg, 49,
Vice President

2011

Portfolio manager and/or analyst, CWAM or its predecessors since 2002; Vice President, Columbia Acorn Trust and Wanger Advisors Trust since 2011.

N/A

Linda Roth-Wiszowaty, 45,
Secretary

2006

Secretary, Columbia Acorn Trust and Wanger Advisors Trust since 2014; Assistant Secretary, Columbia Acorn Trust and Wanger Advisors Trust, 2006-2014; Business support analyst, CWAM since April 2007.

N/A

* Dates prior to April 1992 correspond to the date first elected or appointed as a director or officer of The Acorn Fund Inc., the predecessor to Columbia Acorn Trust.

(1) In addition to the trustees listed below, the Board appointed Charles R. Phillips as a trustee effective January 1, 2015.

(2) Mr. Small resigned from the Board effective December 31, 2014.

(3) Mr. McQuaid is an "interested person" of the Trust and of CWAM, as defined in the 1940 Act, because he is an officer of the Trust and an employee of CWAM.

(4) As permitted under the Trust's Bylaws, Mr. Wanger serves as a non-voting Trustee Emeritus of the Trust.

134

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135

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136

Columbia Acorn Family of Funds Expense Information

as of 12/31/14

Columbia Acorn® Fund	Class A			Class B^(a)			Class C			Class I			Class R			Class R4			Class R5			Class Y			Class Z
Management Fees		0.64	%		0.64	%		0.64	%		0.64	%					0.64	%		0.64	%		0.64	%		0.64	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%		0.00	%					0.00	%		0.00	%		0.00	%		0.00	%
Other Expenses		0.19	%		0.36	%		0.13	%		0.06	%					0.20	%		0.12	%		0.06	%		0.15	%
Net Expense Ratio		1.08	%		1.75	%		1.77	%		0.70	%					0.84	%		0.76	%		0.70	%		0.79	%
Columbia Acorn International®
Management Fees		0.75	%		0.75	%		0.75	%		0.75	%		0.75	%		0.75	%		0.75	%		0.75	%		0.75	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%		0.00	%		0.50	%		0.00	%		0.00	%		0.00	%		0.00	%
Other Expenses		0.22	%		0.47	%		0.22	%		0.10	%		0.38	%		0.29	%		0.15	%		0.10	%		0.18	%
Net Expense Ratio		1.22	%		1.97	%		1.97	%		0.85	%		1.63	%		1.04	%		0.90	%		0.85	%		0.93	%
Columbia Acorn USA®
Management Fees		0.86	%		0.86	%		0.86	%		0.86	%					0.86	%		0.86	%		0.86	%		0.86	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%		0.00	%					0.00	%		0.00	%		0.00	%		0.00	%
Other Expenses		0.22	%		0.65	%		0.14	%		0.02	%					0.21	%		0.13	%		0.07	%		0.22	%
Net Expense Ratio		1.33	%		2.26	%		2.00	%		0.88	%					1.07	%		0.99	%		0.93	%		1.08	%
Columbia Acorn International Select^SM
Management Fees		0.94	%		0.94	%		0.94	%		0.94	%					0.94	%		0.94	%		0.94	%		0.94	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%		0.00	%					0.00	%		0.00	%		0.00	%		0.00	%
Other Expenses		0.28	%		0.42	%		0.29	%		0.17	%					0.27	%		0.21	%		0.15	%		0.23	%
Net Expense Ratio		1.47	%		2.11	%		2.23	%		1.11	%					1.21	%		1.15	%		1.09	%		1.17	%
Columbia Acorn Select^SM
Management Fees		0.85	%		0.85	%		0.85	%		0.85	%					0.85	%		0.85	%		0.85	%		0.85	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%		0.00	%					0.00	%		0.00	%		0.00	%		0.00	%
Other Expenses		0.22	%		0.50	%		0.19	%		0.09	%					0.27	%		0.15	%		0.10	%		0.19	%
Net Expense Ratio		1.32	%		2.10	%		2.04	%		0.94	%					1.12	%		1.00	%		0.95	%		1.04	%
Columbia Thermostat Fund^SM
Management Fees		0.10	%		0.10	%		0.10	%								0.10	%		0.10	%		0.10	%		0.10	%
Distribution and Service (12b-1) Fees		0.25	%		0.75	%		1.00	%								0.00	%		0.00	%		0.00	%		0.00	%
Other Expenses		0.15	%		0.15	%		0.15	%								0.15	%		0.13	%		0.08	%		0.14	%
Net Expense Ratio^(b)		0.50	%		1.00	%		1.25	%								0.25	%		0.23	%		0.18	%		0.24	%
Columbia Acorn Emerging Markets Fund^SM(c)
Management Fees		1.04	%					1.04	%		1.04	%					1.04	%		1.04	%		1.04	%		1.04	%
Distribution and Service (12b-1) Fees		0.25	%					1.00	%		0.00	%					0.00	%		0.00	%		0.00	%		0.00	%
Other Expenses		0.27	%					0.29	%		0.18	%					0.24	%		0.22	%		0.18	%		0.29	%
Net Expense Ratio		1.56	%					2.33	%		1.22	%					1.28	%		1.26	%		1.22	%		1.33	%
Columbia Acorn European Fund^SM
Management Fees		1.19	%					1.19	%		1.19	%					1.19	%		1.19	%					1.19	%
Distribution and Service (12b-1) Fees		0.25	%					1.00	%		0.00	%					0.00	%		0.00	%					0.00	%
Other Expenses		0.31	%					0.31	%		0.27	%					0.31	%		0.33	%					0.31	%
Net Expense Ratio		1.75	%					2.50	%		1.46	%					1.50	%		1.52	%					1.50	%

See the Funds' prospectuses for information on minimum initial investment amounts and other details of buying, selling and exchanging shares of the Funds.

Fees and expenses are for the year ended December 31, 2014. The fees and expenses of Columbia Acorn International Select and Columbia Acorn Select include the effect of the voluntary undertaking by Columbia Wanger Asset Management, LLC (CWAM) to reimburse each Fund so that the ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with the Fund's investment in other investment companies, if any), after giving effect to any balance credits or overdraft charges from the Fund's custodian, do not exceed annually each class' average daily net assets as follows:

Fund	Class A			Class B			Class C			Class I			Class R4			Class R5			Class Y			Class Z
Columbia Acorn International Select		1.70	%		2.20	%		2.45	%		1.37	%		1.45	%		1.42	%		1.37	%		1.45	%
Columbia Acorn Select		1.60	%		2.10	%		2.35	%		1.22	%		1.35	%		1.27	%		1.22	%		1.35	%

These arrangements may be modified or terminated by either the Funds or CWAM on 30 days' notice.

The fees and expenses of Columbia Thermostat Fund include the effect of CWAM's contractual undertaking to waive fees and/or reimburse expenses of the Fund so that the ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with the Fund's investment in underlying portfolio funds), do not exceed annually the rates of 0.50%, 1.00%, 1.25%, 0.25%, 0.23%, 0.18% and 0.25% of the Fund's average daily net assets attributable to Class A, Class B, Class C, Class R4, Class R5, Class Y and Class Z shares, respectively, through April 30, 2015. There is no guarantee that this agreement will continue thereafter.

The fees and expenses of Columbia Acorn Emerging Markets Fund and Columbia Acorn European Fund include the effect of CWAM's contractual undertaking to waive fees and/or reimburse expenses of each Fund so that the ordinary operating expenses (excluding transaction costs and certain other investment-related expenses, interest and fees on borrowings and expenses associated with the Fund's investment in other investment companies, if any), of each Fund's Class A, Class C, Class I, Class R4, Class R5, Class Y (if offered) and Class Z shares through April 30, 2015, do not exceed annually each class' average daily net assets as follows:

Fund	Class A			Class C			Class I			Class R4			Class R5			Class Y			Class Z
Columbia Acorn Emerging Markets Fund		1.85	%		2.60	%		1.46	%		1.60	%		1.51	%		1.46	%		1.60	%
Columbia Acorn European Fund		1.75	%		2.50	%		1.47	%		1.50	%^(d)		1.52	%		—			1.50	%

There is no guarantee that these arrangements will continue thereafter.

The fees and expenses of Columbia Acorn International include the effect of the voluntary undertaking by CMIS to waive a portion of total annual Fund operating expenses attributable to transfer agency expenses incurred by Class A, Class B and Class C shares of Columbia Acorn International such that the Fund's total annual Fund operating expenses will be reduced by 0.04%, 0.03% and 0.02% for Class A, Class B and Class C shares of the Fund, respectively.

^(a) The Funds generally no longer accept investments by new or existing investors in Class B shares, except in connection with the reinvestment of any dividend and/or capital gain distributions in Class B shares of the Funds and exchanges by existing Class B shareholders of certain other funds within the Columbia Acorn Family of Funds.

^(b) Does not include estimated fees and expenses of 0.52% incurred by the Fund from the underlying portfolio funds in which it invests.

^(c) Effective July 11, 2014, Columbia Acorn Emerging Markets Fund is closed to new investors and new accounts, except as described in the Fund's prospectus, dated May 1, 2014, as supplemented June 12, 2014.

^(d) Effective June 25, 2014 (commencement of operations) through April 30, 2015.

137

Columbia Acorn Family of Funds

Trustees

Laura M. Born

Chair of the Board

Steven N. Kaplan

Vice Chair of the Board

Maureen M. Culhane

Margaret M. Eisen

Thomas M. Goldstein

John C. Heaton

Charles P. McQuaid

David J. Rudis

David B. Small*

Ralph Wanger (Trustee Emeritus)

Officers

P. Zachary Egan

President

Robert A. Chalupnik

Vice President

Michael G. Clarke

Assistant Treasurer

Joseph F. DiMaria

Assistant Treasurer

William J. Doyle

Vice President

David L. Frank

Vice President

Fritz Kaegi

Vice President

John M. Kunka

Treasurer and Principal Accounting and Financial Officer

Stephen Kusmierczak

Vice President

Joseph C. LaPalm

Vice President

Charles P. McQuaid

Vice President

Louis J. Mendes III

Vice President

Robert A. Mohn

Vice President

Christopher J. Olson

Vice President

Christopher O. Petersen

Assistant Secretary

Scott R. Plummer

Assistant Secretary

Robert P. Scales

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

Andreas Waldburg-Wolfegg

Vice President

Linda K. Roth-Wiszowaty

Secretary

* Mr. Small resigned from the Board effective December 31, 2014.

Investment Manager

Columbia Wanger Asset Management, LLC
227 West Monroe Street, Suite 3000
Chicago, Illinois 60606

1-800-922-6769

Distributor

Columbia Management Investment Distributors, Inc.
225 Franklin Street
Boston, Massachusetts 02110

Transfer Agent, Dividend Disbursing Agent

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

1-800-345-6611

Legal Counsel to the Funds

Perkins Coie 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, is available from the SEC's website. Information regarding how the Funds voted proxies relating to portfolio securities is also available at www.columbiamanagement.com under "About Us." From there, click on "Disclosures."

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. The Funds' complete portfolio holdings are disclosed at www.columbiamanagement.com approximately 30 to 40 days after each month-end.

Investors should consider the investment objectives, risks, charges and expenses of a mutual fund carefully before investing. For a free prospectus and, if available, a summary prospectus, which contains this and other important information about the funds, visit www.columbiamanagement.com. Read the prospectus carefully before investing.

Columbia Acorn Family of Funds are distributed by Columbia Management Investment Distributors, Inc., member FINRA and managed by Columbia Wanger Asset Management, LLC.

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

www.columbiamanagement.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.

138

This document contains Global Industry Classification Standard data. The Global Industry Classification Standard ("GICS") was developed by and is the exclusive property and a service mark of MSCI Inc. ("MSCI") and Standard & Poor's Financial Services LLC ("S&P") and is licensed for use by Columbia Wanger Asset Management, LLC. Neither MSCI, S&P, nor any other party involved in making or compiling the GICS or any GICS classifications makes any express or implied warranties or representations with respect to such standard or classification (or the results to be obtained by the use thereof), and all such parties hereby expressly disclaim all warranties of originality, accuracy, completeness, merchantability and fitness for a particular purpose with respect to any of such standard or classification. Without limiting any of the foregoing, in no event shall MSCI, S&P, any of their affiliates or any third party involved in making or compiling the GICS or any GICS classifications have any liability for any direct, indirect, special, punitive, consequential or any other damages (including lost profits) even if notified of the possibility of such damages.

Columbia Management^®

Columbia Acorn Family of Funds
Class A, B, C, I, R, R4, R5, Y and Z Shares

Annual Report, December 31, 2014

For More Information

You'll find more information about the Columbia Acorn Family of 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 Investment Services Corp.
P.O. Box 8081
Boston, MA 02266-8081

By Telephone: 800.345.6611

Online: www.columbiamanagement.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, LLC, 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 is a series, is 811-01829.

225 Franklin Street, Boston, MA 02110

800.345.6611 www.columbiamanagement.com

ANN110_12_E01_(02/15) 1122099

Item 2. Code of Ethics.

(a) The registrant has adopted a code of ethics that applies to the registrant’s principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, regardless of whether these individuals are employed by the registrant or a third party.

(b) During the period covered by this report, there were not any amendments to a provision of the code of ethics adopted in 2(a) above.

(c) During the period covered by this report, there were no waivers, including any implicit waivers, from a provision of the code of ethics described in 2(a) above that relates to one or more of the items set forth in paragraph (b) of this item’s instructions.

Item 3. Audit Committee Financial Expert.

The registrant’s Board of Trustees has determined that Thomas Goldstein, a member of the registrant’s Board of Trustees and Audit Committee, qualifies as an audit committee financial expert. Mr. Goldstein is an independent trustee, as defined in paragraph (a)(2) of this item’s instructions.

Item 4. Principal Accountant Fees and Services.

(a) Audit Fees. Aggregate Audit Fees billed by the principal accountant for professional services rendered during the fiscal years ended December 31, 2014 and December 31, 2013 are approximately as follows:

2014		2013
$	319,100	$	304,800

Audit Fees include amounts related to the audit of the registrant’s annual financial statements or services that are normally provided by the accountant in connection with statutory and regulatory filings or engagements for those fiscal years.

(b) Audit-Related Fees. Aggregate Audit-Related Fees billed to the registrant by the principal accountant for professional services rendered during the fiscal years ended December 31, 2014 and December 31, 2013 are approximately as follows:

2014		2013
$	57,200	$	46,000

Audit-Related Fees include amounts for assurance and related services by the principal accountant that are reasonably related to the performance of the audit of the registrant’s financial statements and are not reported in Audit Fees above. In fiscal years 2014 and 2013, Audit-Related Fees consist of agreed-upon procedures performed for other audit-related additional testing.

During the fiscal years ended December 31, 2014 and December 31, 2013, there were no Audit-Related Fees billed by the registrant’s principal accountant to the registrant’s investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for an engagement that related directly to the operations and financial reporting of the registrant.

(c) Tax Fees. Aggregate Tax Fees billed by the principal accountant to the registrant for professional services rendered during the fiscal years ended December 31, 2014 and December 31, 2013 are approximately as follows:

2014		2013
$	62,900	$	59,300

Tax Fees incurred in both fiscal years 2014 and 2013 relate to the review of annual tax returns, the review of required shareholder distribution calculations and include amounts for professional services by the principal accountant for tax compliance, tax advice and tax planning.

During the fiscal years ended December 31, 2014 and December 31, 2013, there were no Tax Fees billed by the registrant’s principal accountant to the registrant’s investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for an engagement that related directly to the operations and financial reporting of the registrant.

(d) All Other Fees. Aggregate All Other Fees billed by the principal accountant to the registrant for professional services rendered during the fiscal years ended December 31, 2014 and December 31, 2013 are as follows:

2014		2013
$	0	$	0

All Other Fees include amounts for products and services provided by the principal accountant, other than the services reported in paragraphs (a) through (c) above.

Aggregate All Other Fees billed by the registrant’s principal accountant to the registrant’s investment adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for an engagement that related directly to the operations and financial reporting of the registrant during the fiscal years ended December 31, 2014 and December 31, 2013 are approximately as follows:

2014		2013
$	325,000	$	135,000

In both fiscal years 2014 and 2013, All Other Fees primarily consist of professional services rendered for internal control reviews.

(e)(1) Audit Committee Pre-Approval Policies and Procedures

The policy of the registrant’s Audit Committee is to specifically pre-approve (i) all audit and non-audit (including audit related, tax and all other) services provided by the registrant’s independent auditor to the registrant and individual funds (collectively “Fund Services”) and (ii) all non-audit services provided by the registrant’s independent auditor to the funds’ adviser or a control affiliate of the adviser, that relate directly to the funds’ operations and financial reporting (collectively “Fund-related Adviser Services”). A “control affiliate” is an entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the funds, and the term “adviser” is deemed to exclude any unaffiliated sub-adviser whose role is primarily portfolio management and is sub-contracted or overseen by another investment adviser.

If such Fund Services or Fund-related Adviser Services are required during the period between the Audit Committee’s regularly scheduled meetings, the Chairman of the Audit Committee has the authority to pre-approve the service, with reporting to the full Audit Committee at the next regularly scheduled meeting.

The Audit Committee will waive pre-approval of Fund Services or Fund-related Adviser Services provided that the requirements under paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X are met.

(e)(2) The percentage of services described in paragraphs (b) through (d) of this Item approved pursuant to the “de minimis” exception under paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X during both fiscal years ended December 31, 2014 and December 31, 2013 was zero.

(f) Not applicable.

(g) The aggregate non-audit fees billed by the registrant’s accountant for services rendered to the registrant, and rendered to the registrant’s investment adviser (not including any sub-adviser whose role is primarily portfolio management and is

subcontracted with or overseen by another investment adviser), and any entity controlling, controlled by, or under common control with the adviser that provides ongoing services to the registrant for the fiscal years ended December 31, 2014 and December 31, 2013 are approximately as follows:

2014		2013
$	445,100	$	240,300

(h) The registrant’s Audit Committee of the Board of Directors has considered whether the provision of non-audit services that were rendered to the registrant’s adviser (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any entity controlling, controlled by, or under common control with the investment adviser that provides ongoing services to the registrant that were not pre-approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of Regulation S-X, is compatible with maintaining the principal accountant’s independence.

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 were no material changes to the procedures by which shareholders may recommend nominees to the registrant’s board of directors.

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 material 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 attached hereto as Exhibit 99.CODE ETH.

(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/ P. Zachary Egan
				P. Zachary Egan, President


Date				February 19, 2015

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/ P. Zachary Egan
			P. Zachary Egan, President


Date			February 19, 2015


By (Signature and Title)			/s/ John M. Kunka
			John M. Kunka, Treasurer


Date			February 19, 2015

Columbia Thermostat Fund (CTFAX) N-CSRCertified annual shareholder report (management investment company)