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 811-06351

Green Century Funds

114 State Street
Suite 200
Boston, MA 02109
(Address of principal executive offices)

Green Century Capital Management, Inc.
114 State Street
Suite 200
Boston, MA 02109
(Name and address of agent for service)

Registrant's telephone number, including area code: (617) 482-0800

Date of fiscal year end: July 31

Date of reporting period: January 31, 2008

Item 1. Reports to Stockholders

The following is a copy of the report transmitted to shareholders pursuant to
Rule 30e-1 under the Investment Company Act of 1940 (17 CFR 270.30e-1).

SEMI-ANNUAL REPORT
Green Century Balanced Fund
Green Century Equity Fund
[LOGO] GREEN CENTURY FUNDS January 31, 2008

An investment for your future.(R) 114 State Street, Boston, Massachusetts 02109

For information on the Green Century Funds(R), call 1-800-93-GREEN. For
information on how to open an account and account services, call
1-800-221-5519 8:00 am to 6:00 pm Eastern Time, Monday through Friday. For
share price and account information, call 1-800-221-5519, twenty-four hours a
day.

Dear Green Century Funds Shareholder:

An article in the March 6, 2008 issue of The Wall Street Journal reported that
according to a recently released report by the Social Investment Forum, the
national membership association for the social investment industry, socially
responsible investment assets in the U.S. surged 18% to $2.71 trillion during
the two-year period ended December 31, 2006. The Social Investment Forum's
study also found that nearly one out of every nine dollars under professional
management in the U.S. is involved in socially responsible investing. As stated
in a March 10, 2008 Investment News article: "A growing desire among investors
to align their portfolios with their personal and political beliefs is
transforming the financial services landscape and creating opportunities and
challenges for financial advisers."

Social Investment Forum Board Chair Cheryl Smith, executive vice president at
Trillium Asset Management Corporation and a portfolio manager of the Green
Century Balanced Fund stated "socially responsible investing is thriving today
as never before. Increasingly, money managers are incorporating social and
environmental factors into their investing practices . . . ."

Environmentally and socially responsible investing is not a new trend at Green
Century Capital Management (Green Century)--Green Century established the Green
Century Funds (the Funds) in 1991 to provide people concerned with the future
of the planet a means to use the clout of their investment dollars to encourage
environmentally responsible corporate behavior. And that is what Green Century
has been doing ever since.

Green Century is proud that Pennsylvania's Treasury Department chose the Green
Century Balanced Fund for a $5 million investment in February as part of the
state's new environmental investment initiative, the Keystone Green Investment
Strategy. This allocation represents one-third of the amount Treasurer Robin L.
Wiessmann has invested in the initial phase of what she terms the "next
frontier of investing" that considers sustainability a long-term investment
consideration.

The Funds were also recently added as an investment option on Social(k), a
defined contribution retirement plan platform which works with companies
operating in a responsible and sustainable manner. Employers can now readily
provide green investment options for their workers, putting long-term
investment capital to work for a cleaner planet. The Funds are offered as an
investment option by other third party administrators of retirement plans as
well.

Just as green investing has been central to Green Century's mission since its
founding, shareholder advocacy has also been critical to our efforts to promote
corporate environmental responsibility. As an active investor and shareholder
advocate, Green Century tells companies how we believe they can improve their
environmental performance. This year, Green Century is the lead filer of a
shareholder resolution at Chevron Corporation/1/ asking the company to report
on the environmental impact of their tar sands oil extraction projects. We are
also advocating that the company consider abandoning its plans to expand these
projects given the significant carbon emissions and environmental damage they
cause. We remind Chevron that logging and oil sands projects have already
reduced the Canadian boreal forests to less than 40% of their original size,
threatening the ecosystem that serves as breeding ground for 30% of North
American songbirds and 40% of waterfowl.

Thank you for investing in the Green Century Funds and joining us in our
efforts to protect the environment and build a sustainable economy.

Respectfully yours,

Green Century Capital Management, Inc.

THE GREEN CENTURY BALANCED FUND

The Green Century Balanced Fund (Balanced Fund) seeks capital growth and income
from a diversified portfolio of stocks and bonds which meet Green Century's
standards for corporate environmental responsibility. Since 1991, Green Century
has sought to promote environmentally responsible corporate behavior, a cleaner
planet and a sustainable economy by investing in companies that Green Century
believes are environmentally responsible and sustainable. The portfolio manager
of the Balanced Fund seeks to invest in companies that are in the business of
solving environmental problems or that are committed to reducing their
environmental impact.

- ----------------------------------------------------------------------------------------
AVERAGE ANNUAL RETURN
- ----------------------------------------------------------------------------------------
Six Months One Year Five Years Ten Years
- ----------------------------------------------------------------------------------------

December 31, 2007 Green Century Balanced Fund -0.43% 3.09% 13.57% 6.31%
Lipper Balanced Fund Index/2/ 0.76% 6.53% 10.33% 6.14%
- ----------------------------------------------------------------------------------------
January 31, 2008 Green Century Balanced Fund -2.17% -2.25% 13.24% 5.81%
Lipper Balanced Fund Index/2/ -0.88% 1.91% 9.92% 5.71%
- ----------------------------------------------------------------------------------------

As of the prospectus dated November 28, 2007, the total annual fund operating
expense ratio of the Balanced Fund is 1.38%.

The performance data quoted represents past performance and is not a
guarantee of future results. Investment return and principal value of an
investment will fluctuate so that an investor's shares, when redeemed, may be
worth more or less than their original cost. Current performance may be lower
or higher than the performance information quoted. To obtain performance
information as of the most recent month-end, call 1-800-93-GREEN. Performance
includes the reinvestment of income dividends and capital gain distributions.
Performance shown does not reflect the deduction of taxes that a shareholder
might pay on Fund distributions or the redemption of Fund shares.

During the six months ended January 31, 2008, the Balanced Fund benefited from
its diversified approach of investing in both stocks and bonds during this
period of market volatility. During the last quarter of calendar year 2007,
bonds rallied as equities slid due to concerns about the sub-prime credit
crisis and the slowdown in the U.S. economy. As the economic outlook has become
more uncertain, the Fund's portfolio manager believes that the chance that the
U.S. is in a recession has risen. In an effort to better position the Fund
under these conditions, the Fund's portfolio manager decreased the Fund's
equity exposure as of January 31, 2008 to 63.6%, down 4.6% from the prior year;
the percentage invested in bonds as of January 31, 2008 was 33.0%, and 3.2% was
held in cash. The portfolio manager anticipates equity markets will continue to
be volatile throughout 2008 but will eventually reach their low point and then
begin to recover by 2009.

GREEN CENTURY BALANCED FUND
INVESTMENTS BY INDUSTRY
[CHART]

Diversified Financials 11.0%
Technology Hardware & Equipment 10.2%
U.S. Government Agencies 10.1%
Healthcare Equipment & Services 9.4%
Capital Goods 7.4%
Telecommunications Services 6.6%
Insurance 5.8%
Renewable Energy & Energy Efficiency 5.3%
Pharmaceuticals & Biotechnology 5.0%
Software & Services 4.6%
Cash Equivalents & Other Assets 3.4%
Food & Beverage 2.9%
Transportation 2.8%
Automobiles & Components 2.8%
Consumer Durables & Apparel 2.2%
Semiconductors 2.1%
Healthy Living 2.0%
Materials 1.9%
Media 1.5%
Banks 1.4%
Food & Staples Retailing 0.6%
Commercial Services & Supplies 0.6%
Retailing 0.4%

During the six months ended January 31, 2008, the Balanced Fund's return was
- -2.17%, underperforming the Lipper Balanced Fund Index by 1.29%. This
underperformance was in part attributable to the strong performance of the
traditional Energy, Materials and Utilities sectors, in which the Balanced Fund
held underweight positions compared to the broader market, as represented by
the S&P 500(R) Index. Fossil fuel prices soared during the period with oil
prices increasing to near $100 per barrel, creating a headwind for the Balanced
Fund with its strong environmental focus and fossil fuel-free portfolio.

As the global economy slows, the Balanced Fund's portfolio manager believes
fossil fuel prices may decline in 2008. As a result, opportunities to increase
the Balanced Fund's exposure to clean technology investments may arise later in
the year. While many clean tech companies are smaller and their share prices
are more volatile than medium and large companies, they can become very
promising long-term investments. The portfolio manager intends to diversify the
Balanced Fund's investments across many sub-sectors under the clean tech
umbrella, including renewable energy, storage technologies, alternative fuels,
energy conversion, and conservation.

Balanced Fund holdings which outperformed during the semi-annual period
included SunPower Corporation/1/, Ecolab, Inc./1/, and Genzyme Corporation/1/,
while poor performers included the American International Group/1/, Barclays
PLC/1/, and Cisco Systems, Inc./1/

The Green Century Balanced Fund invests in stocks and bonds of environmentally
responsible corporations of various sizes, including small, medium, and large
companies. The value of the stocks held in the Balanced Fund will fluctuate in
response to factors that may affect a single issuer, industry, or sector of the
economy or may affect the market as a whole. Bonds are subject to a variety of
risks including interest rate, credit, and inflation risk.

THE GREEN CENTURY EQUITY FUND

The Green Century Equity Fund (Equity Fund) seeks to achieve long-term total
return which matches the performance of the Domini 400 Social/SM/ Index, an
index comprised of the stocks of 400 companies selected based on social and
environmental criteria.

- ------------------------------------------------------------------------------------
AVERAGE ANNUAL RETURN
- ------------------------------------------------------------------------------------
Six Months One Year Five Years Ten Years
- ------------------------------------------------------------------------------------

December 31, 2007 Green Century Equity Fund -2.03% 2.75% 9.93% 4.12%
S&P 500(R) Index/3/ -1.37% 5.49% 12.82% 5.91%
- ------------------------------------------------------------------------------------
January 31, 2008 Green Century Equity Fund -5.03% -5.17% 9.22% 3.29%
S&P 500(R) Index/3/ -4.32% -2.31% 12.03% 5.14%
- ------------------------------------------------------------------------------------

As of the prospectus dated November 28, 2007, the total annual operating
expense ratio of the Equity Fund was 0.95%.

GREEN CENTURY EQUITY FUND
INVESTMENTS BY INDUSTRY
[CHART]

Technology Hardware & Equipment 10.6%
Diversified Financials 8.4%
Pharmaceuticals & Biotechnology 8.3%
Banks 7.9%
Software & Services 6.9%
Telecommunications Services 6.4%
Healthcare Equipment & Services 5.3%
Food & Beverage 5.2%
Household & Personal Products 5.1%
Retailing 4.3%
Energy 4.2%
Capital Goods 4.0%
Semiconductors 3.9%
Insurance 3.1%
Food & Staples Retailing 2.9%
Transportation 2.6%
Media 2.6%
Materials 2.0%
Consumer Durables & Apparel 1.6%
Consumer Services 1.5%
Utilities 1.0%
Real Estate 0.6%
Commercial Services & Supplies 0.6%
Renewable Energy & Energy Efficiency 0.6%
Automobiles & Components 0.2%
Healthy Living 0.1%
Cash Equivalents & Other Assets 0.1%

For the six months ended January 31, 2008, the Equity Fund's return was -5.03%,
while the S&P 500(R) Index's return was -4.32%. The Equity Fund and the overall
economy were hurt by significant economic slowing during the last quarter of
the 2007 calendar year as the credit crunch and housing problems hurt
consumers. Financial companies with mortgage related businesses performed
poorly, as did companies in the Consumer Discretionary and Technology sectors.
Companies that had significant international operations, as well as oil and gas
exploration companies were stronger performers.

For the six months ended January 31, 2008, the performance of the Equity Fund
was helped by investments in companies in the Consumer Staples sector with
reliable cash flows and significant international exposure such as Pepsico,
Inc./1/, Colgate-Palmolive Company/1/, and Procter & Gamble Company/1/. The
Equity Fund's performance relative to the S&P 500(R) Index was aided by the
fact that it did not hold some of the major money center banks whose stocks
performed poorly due to significant write-offs in their mortgage businesses.

Conversely, an overweight position in technology stocks relative to the S&P
500(R) Index hurt the Equity Fund's performance with poor returns from Dell,
Inc./1/, Cisco Systems, Inc./1/, and eBay, Inc./1/ Fear of recession slowed
consumer spending at retailers such as Home Depot, Inc./1/ and J.C. Penney
Company, Inc/1/. The Fund was also hurt by its underweight position relative to
S&P 500(R) Index in the well performing Electric and Utilities sectors.

The Equity Fund invests essentially all its assets in the stock market. As with
all equity funds, the share price will fluctuate and may fall if the market as
a whole declines or the value of the companies in which it invests falls. The
large companies in which the Equity Fund invests may perform worse than the
stock market as a whole.

The Green Century Funds' proxy voting guidelines and a record of the Funds'
proxy votes for the year ended June 30, 2007 are available without charge,
upon request, (i) at www.greencentury.com, (ii) by calling 1-800-93-GREEN,
(iii) sending an e-mail to info@greencentury.com, and (iv) on the Securities
and Exchange Commission's website at www.sec.gov.

The Green Century Funds file their complete schedule of portfolio holdings
with the SEC for the first and third quarters of the year on Form N-Q. The
Green Century Funds' Forms N-Q are available on the EDGAR database on the
SEC's website at www.sec.gov. These Forms may also be reviewed and copied at
the SEC's Public Reference Room in Washington D.C. Information about the
operation of the Public Reference Room may be obtained by calling
1-800-SEC-0330. The information on Form N-Q may also be obtained by calling
1-800-93-GREEN, or by e-mailing a request to info@greencentury.com.

/1/ As of January 31, 2008, neither of the Green Century Funds was invested in
Chevron Corporation. As of January 31, 2008 SunPower Corporation (Class A)
comprised 0.20%, Ecolab, Inc. comprised 0.71%, Genzyme Corporation comprised
1.83%, American International Group comprised 1.17%, Barclays PLC comprised
0.38%, and Cisco Systems, Inc. comprised 1.68% of the Green Century Balanced
Fund's net assets. As of January 31, 2008, Pepsico, Inc. comprised 1.82%,
Colgate-Palmolive Company comprised 0.65%, Procter & Gamble Company comprised
3.38%, Dell, Inc. comprised 0.74%, Cisco Systems, Inc. comprised 2.46%, eBay,
Inc. comprised 0.51%, Home Depot, Inc. comprised 0.85%, and J.C. Penney
Company, Inc. comprised 0.17% of the Green Century Equity Fund's net assets.
Portfolio composition will change due to ongoing management of the Funds.
References to specific investments should not be construed as recommendations
of the securities by the Funds, their administrator, or their distributor.
/2/ Lipper Analytical Services, Inc. (Lipper) is a respected mutual fund
reporting service. The Lipper Balanced Fund Index includes the 30 largest funds
whose primary objective is to conserve principal by maintaining, at all times,
a balanced portfolio of both stocks and bonds. Typically, the stock/bond ratio
ranges around 60%/40%.
/3/ The S&P 500(R) Index is an unmanaged index of 500 selected common stocks,
most of which are listed on the New York Stock Exchange. The S&P 500(R) Index
is heavily weighted toward stocks with large market capitalization and
represents approximately two-thirds of the total market value of all domestic
stocks. It is not possible to invest directly in the S&P 500(R) Index.
This material must be preceded or accompanied by a current prospectus.
Distributor: UMB Distribution Services, LLC, 3/08

GREEN CENTURY FUNDS EXPENSE EXAMPLE
For the six months ended January 31, 2008

As a shareholder of the Green Century Funds (the "Funds"), you incur two types
of costs: (1) transaction costs, including redemption fees on certain
redemptions; and (2) ongoing costs, including management fees; distribution
(12b-1) fees (for the Green Century Balanced Fund only); and other Fund
expenses. This Example is intended to help you understand your ongoing costs
(in dollars) of investing in the Funds and to compare these costs with the
ongoing costs of investing in other mutual funds.

The Example is based on an investment of $1,000 invested at the beginning of
the period and held for the entire period from August 1, 2007 to January 31,
2008 (the "period").

Actual Expenses. In the table below, the first line for each Fund provides
information about actual account values and actual expenses. You may use the
information in this line, together with the amount you invested, to estimate
the expenses you paid over the period. Simply divide your account value by
$1,000 (for example, an $8,600 account value divided by $1,000 equals 8.6),
then multiply the result by the number in the first line under the heading
entitled "Expenses Paid During the Period" to estimate the expenses you paid on
your account during the period.

Hypothetical Example for Comparison Purposes. The second line for each Fund
provides information about hypothetical account values and hypothetical
expenses based on the Funds' actual expense ratios and an assumed rate of
return of 5% per year before expenses, which is not the actual return of either
of the Funds. The hypothetical account values and expenses may not be used to
estimate the actual ending account balance or expenses you paid for the period.
You may use this information to compare the ongoing costs of investing in the
Funds and other funds. To do so, compare this 5% hypothetical example with the
5% hypothetical examples that appear in the shareholder reports of other funds.

Please note that the expenses shown in the table are meant to highlight your
ongoing costs only and do not reflect any transactional costs, such as
redemption fees on shares held for 60 days or less. Therefore, the second line
of the table is useful in comparing the ongoing costs only, and will not help
you determine the relative total costs of owning different funds. In addition,
if these transactional costs were included, your costs could have been higher.

BEGINNING ENDING EXPENSES
ACCOUNT VALUE ACCOUNT VALUE PAID DURING
AUGUST 1, 2007 JANUARY 31, 2008 THE PERIOD/1/
-------------- ---------------- ------------

Balanced Fund
Actual Example......................................... $1,000.00 $ 978.30 $6.86
Hypothetical Example, assuming a 5% return before
expenses.............................................. 1,000.00 1,018.06 7.00

Equity Fund
Actual Example......................................... 1,000.00 949.70 4.65
Hypothetical Example, assuming a 5% return before
expenses.............................................. 1,000.00 1,020.22 4.82

/1/ Expenses are equal to the Funds' annualized expense ratios (1.38% for the
Balanced Fund and 0.95% for the Equity Fund), multiplied by the average account
value over the period, multiplied by 184/366 (to reflect the one-half year
period).

GREEN CENTURY BALANCED FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited)

COMMON STOCKS -- 63.6%
SHARES VALUE
Capital Goods -- 7.4%
3M Company........................ 8,795 $ 700,522
American Superconductor
Corporation (b).................. 8,000 162,000
Emerson Electric Company.......... 21,910 1,113,903
Illinois Tool Works............... 13,990 705,096
Koninklijke Philips Electronics NV
American Depository Receipt (c).. 6,500 256,100
Pentair, Inc...................... 22,000 698,720
-----------
3,636,341
-----------
Technology Hardware & Equipment -- 7.1%
Apple, Inc. (b)................... 2,005 271,397
Cisco Systems, Inc. (b)........... 33,940 831,530
Hewlett-Packard Company........... 28,700 1,255,625
IBM Corporation................... 10,700 1,148,538
-----------
3,507,090
-----------
Insurance -- 5.8%
American International Group...... 10,500 579,180
Chubb Corporation................. 18,670 966,919
Hartford Financial Services Group. 10,750 868,278
Philadelphia Consolidated Holding
Corporation (b).................. 9,025 323,095
WR Berkley Corporation............ 5,000 151,300
-----------
2,888,772
-----------
Healthcare Equipment & Services -- 5.8%
Baxter International, Inc......... 12,600 765,324
Dentsply International, Inc....... 11,400 470,934
Gen-Probe, Inc. (b)............... 2,685 153,448
Hologic, Inc. (b)................. 6,500 418,340
St Jude Medical, Inc. (b)......... 3,700 149,887
UnitedHealth Group, Inc........... 17,410 885,124
-----------
2,843,057
-----------
Renewable Energy & Energy Efficiency -- 5.3%
Active Power, Inc. (b)............ 50,000 109,000
Amerigon, Inc. (b)................ 11,500 196,880
Cree, Inc. (b).................... 7,000 206,850
Echelon Corporation (b)........... 11,000 144,540
First Solar, Inc. (b)............. 515 93,612
Fuel Systems Solutions, Inc. (b).. 9,000 113,940
FuelCell Energy, Inc. (b)......... 21,000 176,610
Itron, Inc. (b)................... 1,990 163,976

SHARES VALUE

Renewable Energy & Energy Efficiency -- (continued)
Johnson Controls, Inc.............. 14,250 $ 504,022
MEMC Electronic Materials,
Inc. (b).......................... 3,600 257,256
OM Group, Inc. (b)................. 4,000 229,520
Ormat Technologies, Inc............ 2,400 104,328
SunPower Corporation, Class A (b).. 1,400 96,726
Suntech Power Holdings Company
Ltd. American Depository
Receipt (b)(c).................... 1,575 86,200
Zoltek Companies, Inc. (b)......... 3,300 120,450
-----------
2,603,910
-----------
Diversified Financials -- 5.0%
American Express Company........... 9,380 462,622
Bank of America Corporation........ 7,470 331,295
Citigroup, Inc..................... 4,830 136,303
Goldman Sachs Group, Inc. (The).... 2,500 501,925
J.P. Morgan Chase & Company........ 21,820 1,037,540
-----------
2,469,685
-----------
Pharmaceuticals & Biotechnology -- 5.0%
Amgen, Inc. (b).................... 4,500 209,655
Barr Pharmaceuticals, Inc. (b)..... 3,090 161,267
Genzyme Corporation (b)............ 11,600 906,309
Johnson & Johnson.................. 13,640 862,866
Teva Pharmaceutical Industries Ltd.
American Depository Receipt (c)... 7,085 326,193
-----------
2,466,290
-----------
Software & Services -- 3.6%
Adobe Systems, Inc. (b)............ 4,000 139,720
Microsoft Corporation.............. 31,650 1,031,790
Oracle Corporation (b)............. 30,200 620,610
-----------
1,792,120
-----------
Telecommunication Services -- 3.3%
AT&T, Inc.......................... 20,500 789,045
BT Group PLC American Depository
Receipt (c)....................... 10,500 544,215
Telefonica S.A. American Depository
Receipt (c)....................... 3,250 285,350
-----------
1,618,610
-----------

GREEN CENTURY BALANCED FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited) continued

SHARES VALUE

Food & Beverage -- 2.9%
General Mills, Inc.................. 14,000 $ 764,540
JM Smucker Company.................. 14,480 676,650
-----------
1,441,190
-----------
Semiconductors -- 2.1%
Applied Materials, Inc.............. 31,350 561,792
Intel Corporation................... 22,000 466,400
-----------
1,028,192
-----------
Materials -- 1.9%
Air Products & Chemicals, Inc....... 6,500 585,130
Ecolab, Inc......................... 7,300 352,225
-----------
937,355
-----------
Automobiles & Components -- 1.8%
Toyota Motor Corporation American
Depository Receipt (c)............. 8,140 883,597
-----------
Transportation -- 1.8%
FedEx Corporation................... 695 64,969
United Parcel Service, Inc., Class B 11,100 812,076
-----------
877,045
-----------
Media -- 1.5%
John Wiley & Sons, Inc.............. 4,000 157,680
McGraw-Hill Companies, Inc.......... 13,960 596,930
-----------
754,610
-----------
Consumer Durables & Apparel -- 1.2%
Deckers Outdoor Corporation (b)..... 1,225 148,519
Jarden Corporation (b).............. 17,300 433,192
-----------
581,711
-----------
Food & Staples Retailing -- 0.6%
Sysco Corporation................... 11,000 319,550
-----------
Commercial Services & Supplies -- 0.6%
Interface, Inc., Class A............ 17,225 274,911
-----------
Retailing -- 0.4%
Men's Wearhouse, Inc................ 7,500 191,175
-----------
Banks -- 0.4%
Barclays PLC American Depository
Receipt (c)........................ 5,000 188,650
-----------

SHARES VALUE

Healthy Living -- 0.1%
Whole Foods Market, Inc....... 1,470 $ 57,977
-----------
Total Common Stocks
(Cost $29,338,502)........... 31,361,838
-----------
CORPORATE BONDS & NOTES -- 22.9%
PRINCIPAL
AMOUNT VALUE
Diversified Financials -- 6.0%
American General Finance
Corporation
5.75%, due 9/15/16.......... $ 500,000 477,588
Fleet National Bank
5.75%, due 1/15/09.......... 500,000 507,343
Goldman Sachs Group, Inc.
6.60%, due 1/15/12.......... 500,000 541,078
J.P. Morgan Chase & Company
4.60%, due 1/17/11.......... 500,000 505,243
J.P. Morgan Chase & Company
4.50%, due 1/15/12.......... 500,000 507,569
Lehman Brothers Holdings, Inc.
5.75%, due 5/17/13.......... 400,000 407,559
-----------
2,946,380
-----------
Healthcare Equipment & Services -- 3.6%
Aetna, Inc.
5.75%, due 6/15/11.......... 595,000 620,979
HCA, Inc.
6.30%, due 10/1/12.......... 1,000,000 917,500
UnitedHealth Group, Inc.
4.875%, due 4/1/13.......... 250,000 252,500
-----------
1,790,979
-----------
Telecommunication Services -- 3.3%
AT&T Corporation
7.30%, due 11/15/11 (e)..... 1,000,000 1,100,487
BellSouth Corporation
4.75%, due 11/15/12......... 500,000 506,747
-----------
1,607,234
-----------
Technology Hardware & Equipment -- 3.1%
Lexmark International, Inc.
6.75%, due 5/15/08.......... 500,000 503,145
Xerox Corporation
7.625%, due 6/15/13......... 1,000,000 1,037,830
-----------
1,540,975
-----------

GREEN CENTURY BALANCED FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited) concluded

PRINCIPAL
AMOUNT VALUE

Healthy Living -- 1.9%
NBTY, Inc.
7.125%, due 10/1/15.......... $1,000,000 $ 935,000
-----------
Software & Services -- 1.0%
Oracle Corporation
5.00%, due 1/15/11........... 500,000 512,584
-----------
Transportation -- 1.0%
Ryder System, Inc.
4.625%, due 4/1/10........... 500,000 512,522
-----------
Banks -- 1.0%
M&I Marshall & Ilsley Bank
3.95%, due 8/14/09........... 500,000 498,652
-----------
Consumer Durables & Apparel -- 1.0%
Newell Rubbermaid, Inc.
4.00%, due 5/1/10............ 500,000 496,810
-----------
Automobiles & Components -- 1.0%
Toyota Motor Credit Corporation
4.125%, due 7/25/17 (c)(e)... 500,000 494,043
-----------
Total Corporate Bonds & Notes
(Cost $11,330,854)........... 11,335,179
-----------
U.S. GOVERNMENT AGENCIES -- 10.1%
Fannie Mae
4.15%, due 9/18/09........... 200,000 200,021
Fannie Mae
5.50%, due 3/1/12............ 283,464 292,824
Fannie Mae
5.05%, due 11/5/12........... 500,000 509,077
Federal Farm Credit Bank
4.50%, due 10/25/11.......... 500,000 524,133
Federal Home Loan Bank
4.60%, due 4/11/08........... 500,000 501,658
Federal Home Loan Bank
4.00%, due 11/26/13 (e)...... 800,000 800,606

PRINCIPAL
AMOUNT VALUE

Federal Home Loan Bank
4.265%, due 7/8/15................. $ 500,000 $ 500,382
SLM Corporation
4.00%, due 7/25/14 (d)............. 2,235,000 1,656,693
-----------
Total U.S. Government Agencies
(Cost $5,470,301)................... 4,985,394
-----------
SHORT TERM OBLIGATION -- 3.2%
Repurchase Agreement --
State Street Bank & Trust
Repurchase Agreement,
1.60%, dated 01/31/08, due
02/01/08, proceeds $1,601,105
(collateralized by a Freddie Mac
Bond, 4.54%, due 08/15/2036,
value at maturity $1,634,328)
(Cost $1,601,034)................... 1,601,034
-----------
TOTAL INVESTMENTS -- 99.8%
(Cost $47,740,691)................. 49,283,445
Other Assets Less Liabilities -- 0.2% 113,830
-----------
NET ASSETS -- 100.0%................. $49,397,275
===========

- --------
(a)The cost of investments for federal income tax purposes is $47,743,945
resulting in gross unrealized appreciation and depreciation of $3,894,731
and $2,355,231 respectively, or net unrealized appreciation of $1,539,500.
(b)Non-income producing security.
(c)Securities whose values are determined or significantly influenced by
trading in markets other than the United States or Canada.
(d)Floating rate bond. Rate shown is currently in effect at January 31, 2008.
(e)Step rate bond. Rate shown is currently in effect at January 31, 2008.

See Notes to Financial Statements

GREEN CENTURY EQUITY FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited)

COMMON STOCKS -- 99.9%
SHARES VALUE
Technology Hardware & Equipment -- 10.6%
3Com Corporation (b)............. 2,700 $ 11,151
Adaptec, Inc. (b)................ 800 2,496
ADC Telecommunications (b)....... 800 11,832
Apple, Inc. (b).................. 5,950 805,391
Arrow Electronics, Inc. (b)...... 850 29,087
Cisco Systems, Inc. (b).......... 41,100 1,006,949
Corning, Inc..................... 10,700 257,549
Dell, Inc. (b)................... 15,200 304,608
EMC Corporation (b).............. 14,250 226,148
Gerber Scientific, Inc. (b)...... 200 1,764
Hewlett-Packard Company.......... 17,450 763,437
Imation Corporation.............. 200 5,182
Lexmark International, Inc. (b).. 650 23,537
Molex, Inc....................... 1,000 24,040
Network Appliance, Inc. (b)...... 2,300 53,406
Palm, Inc........................ 700 3,794
Plantronics, Inc................. 300 5,730
Polycom, Inc. (b)................ 600 15,150
Qualcomm, Inc.................... 11,100 470,862
Seagate Technology............... 3,600 72,972
Sun Microsystems, Inc. (b)....... 5,575 97,563
Tellabs, Inc. (b)................ 2,900 19,778
Xerox Corporation................ 6,200 95,480
-----------
4,307,906
-----------
Diversified Financials -- 8.4%
Allied Capital Corporation....... 1,000 22,130
American Express Company......... 7,900 389,627
Bank of New York Mellon
Corporation (The)............... 7,757 361,708
Capital One Financial Corporation 2,650 145,247
Charles Schwab Corporation....... 6,300 140,490
CIT Group, Inc................... 1,300 36,348
CME Group, Inc................... 380 235,182
Franklin Resources, Inc.......... 1,100 114,653
J.P. Morgan Chase & Company...... 22,800 1,084,139
Janus Capital Group, Inc......... 1,050 28,361
Medallion Financial Corporation.. 100 996
Merrill Lynch & Company, Inc..... 5,750 324,300
Moody's Corporation.............. 1,450 50,736
Northern Trust Corporation....... 1,300 95,368
SLM Corporation.................. 3,500 76,125
State Street Corporation......... 2,600 213,512

SHARES VALUE

Diversified Financials -- (continued)
T. Rowe Price Group, Inc.......... 1,800 $ 91,062
Tradestation Group, Inc. (b)...... 200 2,180
-----------
3,412,164
-----------
Pharmaceuticals & Biotechnology -- 8.3%
Affymetrix, Inc. (b).............. 500 10,030
Allergan, Inc..................... 2,050 137,740
Amgen, Inc. (b)................... 7,350 342,436
Amylin Pharmaceuticals, Inc. (b).. 750 22,238
Biogen Idec, Inc. (b)............. 2,000 121,900
Dionex Corporation (b)............ 150 10,515
Endo Pharmaceuticals Holdings,
Inc. (b)......................... 900 23,526
Forest Laboratories, Inc. (b)..... 2,100 83,517
Genzyme Corporation (b)........... 1,800 140,634
Gilead Sciences, Inc. (b)......... 6,350 290,131
Invitrogen Corporation (b)........ 300 25,701
Johnson & Johnson................. 19,350 1,224,080
King Pharmaceuticals, Inc. (b).... 1,600 16,784
Merck & Co., Inc.................. 14,750 682,629
Millipore Corporation (b)......... 350 24,553
Mylan Laboratories................ 2,000 29,820
Techne Corporation (b)............ 250 16,250
Thermo Fisher Scientific, Inc. (b) 2,850 146,747
Waters Corporation (b)............ 700 40,215
Watson Pharmaceuticals, Inc. (b).. 700 18,277
-----------
3,407,723
-----------
Banks -- 7.9%
Bank of Hawaii Corporation........ 350 17,630
BB&T Corporation.................. 3,700 134,236
Cathay General Bancorp............ 300 7,779
Comerica, Inc..................... 1,000 43,620
Fannie Mae........................ 6,600 223,475
Fifth Third Bancorp............... 3,600 97,560
First Horizon National Corporation 800 17,336
FirstFed Financial Corporation (b) 100 4,195
Freddie Mac....................... 4,450 135,236
Heartland Financial USA, Inc...... 100 1,924
KeyCorp........................... 2,600 67,990
M&T Bank Corporation.............. 500 45,885
MGIC Investment Corporation....... 500 9,250
National City Corporation......... 4,200 74,718
People's United Financial, Inc.... 2,000 33,780

GREEN CENTURY EQUITY FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited) continued

SHARES VALUE

Banks -- (continued)
PNC Financial Services Group.. 2,350 $ 154,207
Popular, Inc.................. 1,900 25,688
Regions Financial Corporation. 4,700 118,628
Sovereign Bancorp, Inc........ 2,400 29,928
SunTrust Banks, Inc........... 2,350 162,033
Synovus Financial Corporation. 2,200 29,062
U.S. Bancorp.................. 11,650 395,517
Wachovia Corporation.......... 13,392 521,350
Wainwright Bank Trust Company. 52 665
Washington Mutual, Inc........ 5,800 115,536
Wells Fargo & Company......... 22,850 777,128
-----------
3,244,356
-----------
Software & Services -- 6.9%
Adobe Systems, Inc. (b)....... 3,850 134,481
Advent Software, Inc. (b)..... 100 4,516
Autodesk, Inc. (b)............ 1,550 63,783
Automatic Data Processing..... 3,550 144,023
BMC Software, Inc. (b)........ 1,300 41,652
Compuware Corporation (b)..... 1,900 16,150
Convergys Corporation (b)..... 900 13,959
eBay, Inc. (b)................ 7,750 208,397
Electronic Arts, Inc. (b)..... 2,100 99,477
Electronic Data Systems
Corporation.................. 3,500 70,350
Microsoft Corporation......... 54,500 1,776,699
Novell, Inc. (b).............. 2,300 14,628
Paychex, Inc.................. 2,250 73,620
Red Hat, Inc. (b)............. 1,300 24,284
Salesforce.com, Inc. (b)...... 550 28,754
Sapient Corporation (b)....... 700 4,907
Symantec Corporation (b)...... 5,750 103,098
Unisys Corporation (b)........ 2,300 9,568
-----------
2,832,346
-----------
Telecommunication Services -- 6.4%
AT&T, Inc..................... 41,125 1,582,901
Citizens Communications
Company...................... 2,300 26,381
Sprint Nextel Corporation..... 19,250 202,703
Telephone & Data Systems, Inc. 700 36,918
Verizon Communications, Inc... 19,550 759,322
-----------
2,608,225
-----------

SHARES VALUE

Healthcare Equipment & Services -- 5.3%
Baxter International, Inc......... 4,250 $ 258,145
Becton Dickinson & Company........ 1,650 142,775
C.R. Bard, Inc.................... 700 67,599
CIGNA Corporation................. 1,900 93,404
Cross Country Healthcare, Inc. (b) 200 2,526
Edwards Lifesciences
Corporation (b).................. 400 18,508
Gen-Probe, Inc. (b)............... 350 20,003
Health Management Associates,
Class A.......................... 1,600 8,624
Hillenbrand Industries............ 400 20,688
Humana, Inc. (b).................. 1,150 92,345
Idexx Laboratories, Inc. (b)...... 400 22,548
IMS Health, Inc................... 1,300 31,057
Invacare Corporation.............. 200 4,868
McKesson Corporation.............. 1,950 122,441
Medtronic, Inc.................... 7,700 358,588
Molina Healthcare, Inc. (b)....... 100 3,411
Patterson Companies, Inc. (b)..... 950 30,438
Quest Diagnostics................. 1,050 51,786
Sierra Health Services (b)........ 400 17,192
St Jude Medical, Inc. (b)......... 2,300 93,173
Stryker Corporation............... 1,600 107,152
UnitedHealth Group, Inc........... 8,800 447,391
Varian Medical Systems, Inc. (b).. 850 44,192
Zimmer Holdings, Inc. (b)......... 1,600 125,232
-----------
2,184,086
-----------
Food & Beverage -- 5.2%
Campbell Soup Company............. 1,500 47,415
Chiquita Brands International (b). 300 5,604
Coca-Cola Company (The)........... 13,500 798,794
Dean Foods Company................ 900 25,200
Flowers Foods, Inc................ 500 12,000
General Mills, Inc................ 2,250 122,873
Green Mountain Coffee Roasters,
Inc. (b)......................... 100 3,852
H.J. Heinz Company................ 2,150 91,504
Hershey Company (The)............. 1,150 41,630
JM Smucker Company................ 400 18,692
Kellogg Company................... 1,800 86,220
McCormick & Company, Inc.......... 850 28,662
PepsiAmericas, Inc................ 400 9,856
Pepsico, Inc...................... 10,950 746,680

GREEN CENTURY EQUITY FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited) continued

SHARES VALUE

Food & Beverage -- (continued)
Tootsie Roll Industries, Inc...... 206 $ 5,146
Wm. Wrigley Jr. Company........... 1,450 83,274
-----------
2,127,402
-----------
Household & Personal Products -- 5.1%
Alberto-Culver Company............ 600 16,074
Avon Products, Inc................ 2,900 101,558
Church & Dwight Company, Inc...... 450 23,949
Clorox Company.................... 950 58,254
Colgate-Palmolive Company......... 3,450 265,650
Energizer Holdings, Inc. (b)...... 400 37,448
Estee Lauder Companies, Inc.
(The), Class A................... 750 31,650
Kimberly-Clark Corporation........ 2,850 187,103
Nu Skin Enterprises, Inc., Class A 300 4,929
Procter & Gamble Company.......... 21,000 1,384,950
-----------
2,111,565
-----------
Retailing -- 4.3%
Autozone, Inc. (b)................ 300 36,264
Bed Bath & Beyond, Inc. (b)....... 1,800 58,032
Best Buy Company, Inc............. 2,350 114,704
Carmax, Inc. (b).................. 1,500 33,450
Charming Shoppes, Inc. (b)........ 800 5,160
Circuit City Stores, Inc.......... 1,100 5,984
Family Dollar Stores.............. 1,000 21,030
Foot Locker, Inc.................. 1,000 13,690
Gap, Inc.......................... 3,150 60,228
Genuine Parts Company............. 1,150 50,520
Home Depot, Inc................... 11,400 349,637
J.C. Penney Company, Inc.......... 1,500 71,115
Limited Brands.................... 2,100 40,089
Lowe's Companies, Inc............. 9,900 261,756
Men's Wearhouse, Inc.............. 400 10,196
Nordstrom, Inc.................... 1,250 48,625
Office Depot, Inc. (b)............ 1,800 26,694
Pep Boys--Manny, Moe & Jack....... 300 3,279
Radioshack Corporation............ 900 15,615
Staples, Inc...................... 4,800 114,912
Target Corporation................ 5,600 311,248
Tiffany & Company................. 900 35,910
TJX Companies, Inc................ 3,000 94,680
-----------
1,782,818
-----------

SHARES VALUE

Energy -- 4.2%
Apache Corporation.............. 2,250 $ 214,740
Cameron International
Corporation (b)................ 1,500 60,390
Chesapeake Energy Corporation... 3,050 113,552
Devon Energy Corporation........ 3,000 254,939
EOG Recources, Inc.............. 1,650 144,375
Grant Prideco, Inc. (b)......... 850 42,313
Helmerich & Payne............... 700 27,454
National Oilwell Varco, Inc. (b) 2,400 144,552
Newfield Exploration Company (b) 900 44,892
Noble Energy, Inc............... 1,150 83,467
Pioneer Natural Resources
Company........................ 800 33,520
Rowan Companies, Inc............ 750 25,530
Smith International, Inc........ 1,350 73,184
Spectra Energy Corporation...... 4,300 98,212
Sunoco, Inc..................... 800 49,760
Williams Companies, Inc......... 4,000 127,880
XTO Energy, Inc................. 3,250 168,805
-----------
1,707,565
-----------
Capital Goods -- 4.0%
3M Company...................... 4,800 382,319
A.O. Smith Corporation.......... 150 5,250
Aecom Technology Corporation (b) 300 7,389
Apogee Enterprises, Inc......... 200 3,490
Baldor Electric Company......... 300 9,084
CLARCOR, Inc.................... 350 13,129
Cooper Industries, Inc., Class A 1,200 53,448
Cummins, Inc.................... 1,400 67,592
Deere & Company................. 3,000 263,279
Donaldson Company, Inc.......... 500 20,950
EMCOR Group, Inc. (b)........... 400 8,772
Emerson Electric Company........ 5,300 269,451
Fastenal Company................ 850 34,349
GATX Corporation................ 300 11,280
Graco, Inc...................... 400 13,688
Granite Construction, Inc....... 250 9,518
Hubbell, Inc., Class B.......... 400 19,072
Illinois Tool Works............. 2,800 141,120
Kadant, Inc. (b)................ 100 2,643
Lawson Products, Inc............ 50 1,589
Lincoln Electric Holdings....... 300 18,495
Masco Corporation............... 2,500 57,325

GREEN CENTURY EQUITY FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited) continued

SHARES VALUE

Capital Goods -- (continued)
NCI Building Systems, Inc. (b)... 100 $ 2,876
Nordson Corporation.............. 250 12,470
Pall Corporation................. 850 31,357
Quanta Services, Inc. (b)........ 1,200 26,304
Rockwell Automation, Inc......... 1,000 57,020
Simpson Manufacturing
Company, Inc.................... 300 8,265
SPX Corporation.................. 350 35,210
Tennant Company.................. 150 4,949
Thomas & Betts Corporation (b)... 350 15,838
Toro Company..................... 250 12,335
Trex Company, Inc. (b)........... 100 825
W.W. Grainger, Inc............... 450 35,807
-----------
1,656,488
-----------
Semiconductors -- 3.9%
Advanced Micro Devices (b)....... 4,000 30,560
Analog Devices................... 2,050 58,138
Applied Materials, Inc........... 9,300 166,656
Entegris, Inc. (b)............... 800 6,160
Intel Corporation................ 39,600 839,520
Lam Research Corporation (b)..... 900 34,551
LSI Corporation (b).............. 4,800 25,056
Micron Technology, Inc. (b)...... 5,000 35,150
National Semiconductor
Corporation..................... 1,600 29,488
Novellus Systems, Inc. (b)....... 800 19,008
Texas Instruments, Inc........... 9,500 293,835
Xilinx, Inc...................... 2,000 43,740
-----------
1,581,862
-----------
Insurance -- 3.1%
Aflac, Inc....................... 3,300 202,389
Ambac Financial Group, Inc....... 700 8,204
Chubb Corporation................ 2,600 134,654
Cincinnati Financial Corporation. 1,100 42,394
Erie Indemnity Company........... 300 15,189
Hartford Financial Services Group 2,100 169,617
Lincoln National Corporation..... 1,800 97,848
Marsh & McLennan Companies....... 3,500 96,600
MBIA, Inc........................ 800 12,400
Phoenix Companies, Inc. (The).... 800 8,664
Principal Financial Group........ 1,750 104,318
Progressive Corporation.......... 4,700 87,232

SHARES VALUE

Insurance -- (continued)
Safeco Corporation.................. 650 $ 34,691
Travelers Companies, Inc. (The)..... 4,350 209,234
Unum Group.......................... 2,400 54,288
Wesco Financial Corporation......... 10 3,960
-----------
1,281,682
-----------
Food & Staples Retailing -- 2.9%
Costco Wholesale Corporation........ 2,900 197,026
CVS Caremark Corporation............ 10,050 392,654
Kroger Company...................... 4,600 117,070
Longs Drugstores Corporation........ 200 9,202
Safeway, Inc........................ 3,000 92,970
Supervalu, Inc...................... 1,400 42,084
Sysco Corporation................... 4,100 119,105
Walgreen Company.................... 6,700 235,237
-----------
1,205,348
-----------
Transportation -- 2.6%
Alaska Air Group, Inc. (b).......... 300 7,590
AMR Corporation (b)................. 1,700 23,698
Arkansas Best Corporation........... 200 6,158
Expeditors International
Washington, Inc.................... 1,450 68,571
FedEx Corporation................... 2,100 196,308
JetBlue Airways (b)................. 1,200 8,292
Kansas City Southern (b)............ 500 17,940
Norfolk Southern Corporation........ 2,600 141,414
Ryder System, Inc................... 400 20,824
Southwest Airlines.................. 5,000 58,650
United Parcel Service, Inc., Class B 7,100 519,436
YRC Worldwide, Inc. (b)............. 400 7,324
-----------
1,076,205
-----------
Media -- 2.6%
E.W. Scripps Company (The),
Class A............................ 600 24,432
Emmis Communications,
Class A (b)........................ 200 558
Lee Enterprises, Inc................ 300 3,582
McClatchy Company (The)............. 400 4,308
McGraw-Hill Companies, Inc.......... 2,200 94,072
Meredith Corporation................ 250 11,748
New York Times Company,
Class A............................ 1,000 16,740

GREEN CENTURY EQUITY FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited) continued

SHARES VALUE

Media -- (continued)
Omnicom Group.................... 2,200 $ 99,814
Scholastic Corporation (b)....... 200 6,854
Time Warner, Inc................. 24,450 384,843
Valassis Communications (b)...... 300 2,868
Walt Disney Company (The)........ 12,900 386,097
Washington Post Company,
Class B......................... 40 29,760
-----------
1,065,676
-----------
Materials -- 2.0%
Air Products & Chemicals, Inc.... 1,450 130,528
Airgas, Inc...................... 550 25,526
Bemis Company.................... 700 19,026
Cabot Corporation................ 450 13,379
Calgon Carbon Corporation (b).... 300 4,614
Crown Holdings, Inc. (b)......... 1,100 26,972
Ecolab, Inc...................... 1,200 57,900
H.B. Fuller Company.............. 400 8,304
Lubrizol Corporation............. 450 23,675
MeadWestvaco Corporation......... 1,250 35,000
Minerals Technologies, Inc....... 150 8,160
Nucor Corporation................ 1,950 112,710
Praxair, Inc..................... 2,150 173,956
Rock-Tenn Company, Class A....... 200 5,718
Rohm and Hass Company............ 850 45,348
Schnitzer Steel Industries, Inc.,
Class A......................... 150 8,499
Sealed Air Corporation........... 1,100 28,765
Sigma-Aldrich Corporation........ 900 44,694
Sonoco Products Company.......... 650 20,059
Valspar Corporation.............. 700 14,021
Wausau Paper Corporation......... 300 2,685
Worthington Industries........... 400 6,556
-----------
816,095
-----------
Consumer Durables & Apparel -- 1.6%
American Greetings Corporation,
Class A......................... 400 8,208
Black & Decker Corporation....... 400 29,016
Centex Corporation............... 800 22,224
Champion Enterprises, Inc. (b)... 500 4,885
Coach, Inc. (b).................. 2,500 80,125
D.R. Horton, Inc................. 1,800 31,050
Deckers Outdoor Corporation (b).. 100 12,124

SHARES VALUE

Consumer Durables & Apparel -- (continued)
Harman International............. 400 $ 18,628
Hartmarx Corporation (b)......... 200 540
KB Home.......................... 500 13,750
Leggett & Platt, Inc............. 1,200 22,824
Liz Claiborne, Inc............... 700 15,323
Mattel, Inc...................... 2,450 51,475
Newell Rubbermaid, Inc........... 1,900 45,828
Nike, Inc., Class B.............. 2,600 160,576
Phillips-Van Heusen Corporation.. 400 16,856
Pulte Homes, Inc................. 1,400 22,876
Snap-On, Inc..................... 400 19,648
Stanley Works (The).............. 550 28,248
Timberland Company (The) (b)..... 300 4,923
Tupperware Brands Corporation.... 400 14,800
Whirlpool Corporation............ 500 42,555
-----------
666,482
-----------
Consumer Services -- 1.5%
Bright Horizons Family Solutions,
Inc. (b)........................ 200 8,514
Choice Hotels International, Inc. 200 6,680
Darden Restaurants, Inc.......... 1,000 28,320
DeVry, Inc....................... 400 22,076
McDonald's Corporation........... 8,050 431,078
Starbucks Corporation (b)........ 4,900 92,659
Wendy's International, Inc....... 600 14,652
-----------
603,979
-----------
Utilities -- 1.0%
AGL Resources, Inc............... 500 18,925
Alliant Energy Corporation....... 750 27,675
Atmos Energy Corporation......... 600 17,232
Avista Corporation............... 400 8,060
Cleco Corporation................ 400 10,340
Energen Corporation.............. 500 31,450
Equitable Resources, Inc......... 800 44,600
IDACORP, Inc..................... 300 9,792
MGE Energy, Inc.................. 150 4,914
National Fuel Gas Company........ 550 23,711
Nicor, Inc....................... 300 12,300
NiSource, Inc.................... 1,900 36,081
Northwest Natural Gas Company.... 200 9,468
OGE Energy Corporation........... 600 19,638
Pepco Holdings, Inc.............. 1,400 35,644

GREEN CENTURY EQUITY FUND PORTFOLIO OF INVESTMENTS
January 31, 2008
(unaudited) concluded

SHARES VALUE

Utilities -- (continued)
Questar Corporation.............. 1,150 $ 58,546
Southern Union Company........... 800 21,744
WGL Holdings..................... 350 11,284
-----------
401,404
-----------
Real Estate -- 0.6%
CB Richard Ellis Group, Inc.,
Class A (b)..................... 1,300 25,233
General Growth Properties........ 1,650 60,258
Jones Lang LaSalle, Inc.......... 250 19,450
Liberty Property Trust........... 600 19,266
Maguire Properties, Inc.......... 300 8,274
ProLogis......................... 1,750 103,862
Regency Centers Corporation...... 450 27,644
-----------
263,987
-----------
Commercial Services & Supplies -- 0.6%
Avery Dennison Corporation....... 700 36,274
Brady Corporation, Class A....... 350 10,630
Deluxe Corporation............... 350 8,512
Herman Miller, Inc............... 400 12,712
HNI Corporation.................. 300 10,098
IKON Office Solutions, Inc....... 800 6,544
Interface, Inc., Class A......... 400 6,384
Kelly Services................... 200 3,444
Monster Worldwide, Inc. (b)...... 850 23,673
Pitney Bowes, Inc................ 1,450 53,214
R.R. Donnelley & Sons Company.... 1,450 50,591
Robert Half International, Inc... 1,100 30,558
Standard Register................ 100 972
Steelcase, Inc................... 500 7,665
-----------
261,271
-----------
Renewable Energy & Energy Efficiency -- 0.6%
Energy Conversion Devices (b).... 250 5,770
First Solar, Inc. (b)............ 250 45,443
Itron, Inc. (b).................. 200 16,480
Johnson Controls, Inc............ 4,000 141,480
Ormat Technologies, Inc.......... 100 4,347
SunPower Corporation, Class A (b) 200 13,818
Zoltek Companies, Inc. (b)....... 150 5,475
-----------
232,813
-----------

SHARES VALUE

Automobiles & Components -- 0.2%
Cooper Tire & Rubber................. 400 $ 6,828
Harley-Davidson, Inc................. 1,650 66,957
Modine Manufacturing Company......... 200 3,088
Spartan Motors, Inc.................. 225 2,018
-----------
78,891
-----------
Healthy Living -- 0.1%
Gaiam, Inc. (b)...................... 100 2,437
Hain Celestial Group, Inc. (The) (b). 250 6,750
United Natural Foods, Inc. (b)....... 300 7,194
Whole Foods Market, Inc.............. 950 37,468
-----------
53,849
-----------
Total Securities
(Cost $41,994,591).................. 40,972,188
-----------
SHORT TERM OBLIGATION -- 0.1%
Repurchase Agreement --
State Street Bank & Trust
Repurchase Agreement,
1.60%, dated 01/31/08, due
02/01/08, proceeds $29,056
(collateralized by Freddie Mac Giant
Bonds, 4.50%, due 12/01/2020,
value at maturity $32,337)
(Cost $29,055)...................... 29,055
-----------
TOTAL INVESTMENTS -- 100.0%
(Cost $42,023,646)................. 41,001,243
Other Assets Less Liabilities -- 0.0% 1,697
-----------
NET ASSETS -- 100.0%................. $41,002,940
===========

- --------
(a)The cost of investments for federal income tax purposes is $42,084,719
resulting in gross unrealized appreciation and depreciation of $3,158,188
and $4,241,664 respectively, or net unrealized depreciation of $1,083,476.
(b)Non-income producing security

See Notes to Financial Statements

GREEN CENTURY FUNDS STATEMENT OF ASSETS AND LIABILITIES
January 31, 2008
(unaudited)

BALANCED FUND EQUITY FUND
------------- -----------

ASSETS:
Investments, at value (cost $47,740,691 and $42,023,646, respectively) $ 49,283,445 $41,001,243
Receivables for:
Capital stock sold.................................................. 7,108 5,057
Interest............................................................ 166,156 1
Dividends........................................................... 38,837 55,772
------------ -----------
Total assets....................................................... 49,495,546 41,062,073
------------ -----------
LIABILITIES:
Payable for capital stock repurchased................................. 40,331 27,830
Accrued expenses...................................................... 57,940 31,303
------------ -----------
Total liabilities.................................................. 98,271 59,133
------------ -----------
NET ASSETS............................................................ $ 49,397,275 $41,002,940
============ ===========
NET ASSETS CONSIST OF:
Paid-in capital....................................................... $ 59,695,111 $42,036,694
Undistributed net investment income................................... (24,947) 31,699
Accumulated net realized (losses) on investments...................... (11,815,643) (43,050)
Net unrealized appreciation (depreciation) on investments............. 1,542,754 (1,022,403)
------------ -----------
NET ASSETS............................................................ $ 49,397,275 $41,002,940
============ ===========
SHARES OUTSTANDING.................................................... 2,864,924 2,003,206
============ ===========
NET ASSET VALUE, REDEMPTION PRICE AND OFFERING PRICE PER SHARE........ $ 17.24 $ 20.47
============ ===========

GREEN CENTURY FUNDS STATEMENT OF OPERATIONS
For the period ended January 31, 2008
(unaudited)

BALANCED FUND EQUITY FUND
- - ------------- -----------

INVESTMENT INCOME:
Interest income............................................. $ 461,160 $ 2,290
Dividend income (net of $1,802 and $30 foreign withholding
taxes, respectively)....................................... 288,512 402,159
----------- -----------
Total investment income.................................. 749,672 404,449
----------- -----------
EXPENSES:
Administrative services fee................................. 189,730 152,218
Investment advisory fee..................................... 168,968 54,377
----------- -----------
Total expenses........................................... 358,698 206,595
----------- -----------
NET INVESTMENT INCOME....................................... 390,974 197,854
----------- -----------
NET REALIZED AND UNREALIZED GAINS (LOSSES):
Net realized gains (losses) on investments:................. 144,935 (29,242)
Change in net unrealized depreciation on investments:....... (1,623,746) (2,316,610)
----------- -----------
NET REALIZED AND UNREALIZED LOSSES ON INVESTMENTS........... (1,478,811) (2,345,852)
----------- -----------
NET DECREASE IN NET ASSETS RESULTING FROM OPERATIONS........ $(1,087,837) $(2,147,998)
=========== ===========

See Notes to Financial Statements

GREEN CENTURY FUNDS STATEMENTS OF CHANGES IN NET ASSETS

BALANCED FUND EQUITY FUND
----------------------------- -----------------------------
FOR THE SIX FOR THE FOR THE SIX FOR THE
MONTHS ENDED YEAR ENDED MONTHS ENDED YEAR ENDED
JANUARY 31, 2008 JULY 31, 2007 JANUARY 31, 2008 JULY 31, 2007
(UNAUDITED) (AUDITED) (UNAUDITED) (AUDITED)

INCREASE (DECREASE) IN NET ASSETS:
From operations:
Net investment income.................................. $ 390,974 $ 660,398 $ 197,854 $ 347,827
Net realized gains (losses) on:
Investments........................................... 144,935 1,970,834 (29,242) 67,872
Investments allocated from Domini Trust............... -- -- -- 298,836
Withdrawal of investment from Domini Trust............ -- -- -- 9,896,339
Change in net unrealized appreciation/depreciation on:
Investments........................................... (1,623,746) 2,617,738 (2,316,610) 1,294,207
Investments allocated from Domini Trust............... -- -- -- (7,010,701)
----------- ----------- ----------- -----------
Net increase (decrease) in net assets resulting from
operations............................................ (1,087,837) 5,248,970 (2,147,998) 4,894,380
----------- ----------- ----------- -----------
Dividends and distributions to shareholders:
From net investment income............................. (462,060) (612,601) (216,874) (335,455)
From net realized gains................................ -- -- (1,920,696) --
----------- ----------- ----------- -----------
Total dividends and distributions...................... (462,060) (612,601) (2,137,570) (335,455)
----------- ----------- ----------- -----------
Capital share transactions:
Proceeds from sales of shares.......................... 2,240,176 4,939,216 3,812,776 9,725,081
Reinvestment of dividends and distributions............ 447,104 593,710 2,113,950 329,289
Payments for shares redeemed........................... (3,493,664) (8,645,516) (2,870,005) (5,319,171)
----------- ----------- ----------- -----------
Net increase (decrease) in net assets resulting from
capital share transactions............................ (806,384) (3,112,590) 3,056,721 4,735,199
----------- ----------- ----------- -----------
Total increase (decrease) in net assets.................. (2,356,281) 1,523,779 (1,228,847) 9,294,124
NET ASSETS:
Beginning of period.................................... 51,753,556 50,229,777 42,231,787 32,937,663
----------- ----------- ----------- -----------
End of period.......................................... $49,397,275 $51,753,556 $41,002,940 $42,231,787
=========== =========== =========== ===========
Undistributed net investment income.................... (24,947) 46,139 31,699 50,719

See Notes to Financial Statements

GREEN CENTURY BALANCED FUND FINANCIAL HIGHLIGHTS

SIX MONTHS ENDED
JANUARY 31, 2008 FOR THE YEARS ENDED JULY 31,
---------------- --------------------------------------------
(UNAUDITED) 2007 2006 2005 2004 2003

Net Asset Value, beginning of period........................ $ 17.78 $ 16.29 $ 16.52 $ 14.11 $ 13.88 $ 10.30
------- ------- ------- ------- ------- -------
Income from investment operations:
Net investment income...................................... 0.14 0.22 0.03 0.05 0.12 0.16
Net realized and unrealized gain (loss) on investments..... (0.52) 1.48 (0.23) 2.42 0.23 3.59
------- ------- ------- ------- ------- -------
Total increase (decrease) from investment operations........ (0.38) 1.70 (0.20) 2.47 0.35 3.75
------- ------- ------- ------- ------- -------
Less dividends:
Dividends from net investment income....................... (0.16) (0.21) (0.03) (0.06) (0.12) (0.17)
------- ------- ------- ------- ------- -------
Net Asset Value, end of period.............................. $ 17.24 $ 17.78 $ 16.29 $ 16.52 $ 14.11 $ 13.88
======= ======= ======= ======= ======= =======
Total return................................................ (2.17)%(a) 10.40% (1.22)% 17.41% 2.49% 36.83%
Ratios/Supplemental data:
Net assets, end of period (in 000's)....................... $49,397 $51,754 $50,230 $62,449 $50,398 $71,306
Ratio of expenses to average net assets.................... 1.38%(b) 1.44% 2.39% 2.38% 2.37% 2.44%
Ratio of net investment income to average net assets....... 1.50%(b) 1.24% 0.15% 0.35% 0.71% 1.51%
Portfolio turnover......................................... 21%(a) 35% 110% 86% 81% 94%

(a)Not annualized
(b)Annualized

GREEN CENTURY EQUITY FUND FINANCIAL HIGHLIGHTS

SIX MONTHS ENDED
JANUARY 31, 2008 FOR THE YEARS ENDED JULY 31,
---------------- -------------------------------------------------------
(UNAUDITED) 2007 2006 2005 2004 2003

Net Asset Value, beginning of period.............. $ 22.66 $ 19.91 $ 19.91 $ 18.18 $ 16.45 $ 14.85
------- ------- ------- ------- ------- -------
Income from investment operations:
Net investment income............................ 0.10 0.19 0.04 0.12 -- 0.01
Net realized and unrealized gain (loss) on
investments.................................... (1.17) 2.75 (0.01) 1.72 1.74 1.59
------- ------- ------- ------- ------- -------
Total increase/(decrease) from investment
operations....................................... (1.07) 2.94 0.03 1.84 1.74 1.60
------- ------- ------- ------- ------- -------
Less dividends:
Dividends from net investment income............. (0.11) (0.19) (0.03) (0.11) (0.01) --
Distributions from net realized gains............ (1.01) -- -- -- -- --
------- ------- ------- ------- ------- -------
Total decrease from dividends..................... (1.12) (0.19) (0.03) (0.11) (0.01) --
------- ------- ------- ------- ------- -------
Net Asset Value, end of period.................... $ 20.47 $ 22.66 $ 19.91 $ 19.91 $ 18.18 $ 16.45
======= ======= ======= ======= ======= =======
Total return...................................... (5.03)%(b) 14.76% 0.16% 10.10% 10.61% 10.77%
Ratios/Supplemental data:
Net assets, end of period (in 000's)............. $41,003 $42,232 $32,938 $35,383 $33,152 $29,347
Ratio of expenses to average net assets.......... 0.95%(c) 0.95% 1.50% 1.50% 1.50% 1.50%
Ratio of net investment income (loss) to average
net assets..................................... 0.91%(c) 0.89% 0.20% 0.64% (0.01)% 0.05%
Portfolio turnover............................... 3%(b) 8%(d) 12%(a) 9%(a) 8%(a) 8%(a)

(a)Represents portfolio turnover for the Domini Social Equity Trust ("Domini
Trust") for the years ended 2006, 2005, 2004 and 2003.
(b)Not annualized.
(c)Annualized.
(d)Represents portfolio turnover for the Equity Fund from November 28, 2006 to
July 31, 2007. Portfolio turnover for the Domini Trust from August 1, 2006
to November 27, 2006 was 1%. For further information regarding the
withdrawal of the Equity Fund's investment in the Domini Trust, please see
the notes to the financial statements.

See Notes to Financial Statements

GREEN CENTURY FUNDS NOTES TO FINANCIAL STATEMENTS
(unaudited)

NOTE 1 -- Organization and Significant Accounting Policies
Green Century Funds (the "Trust") is a Massachusetts business trust which
offers two separate series, the Green Century Balanced Fund (the "Balanced
Fund") and the Green Century Equity Fund (the "Equity Fund"), collectively, the
"Funds". The Trust is registered under the Investment Company Act of 1940, as
amended (the "Act"), as an open-end management investment company. The Trust
accounts separately for the assets, liabilities and operations of each series.
The Balanced Fund commenced operations on March 18, 1992 and the Equity Fund
commenced operations on September 13, 1995.

Through November 27, 2006, the Equity Fund invested substantially all of its
assets in the Domini Social Equity Trust (the "Domini Trust"), an open-end,
diversified management investment company which had the same investment
objective as the Fund. The Equity Fund accounted for its investment in the
Domini Trust as a partnership investment and recorded its share of the Domini
Trust income, expenses and realized and unrealized gains and losses daily. The
value of such investment reflected the Fund's proportionate interest in the net
assets of the Domini Trust (2.57% at November 27, 2006). Effective November 28,
2006, the Equity Fund withdrew its investment from the Domini Trust and
directly invested in the securities of the companies included in the Domini 400
Social/SM/ Index (the "Domini Index").

The preparation of financial statements in conformity with U.S. generally
accepted accounting principles requires management to make estimates and
assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting period. Actual results could differ from those estimates. The
following is a summary of the Funds' significant accounting policies:

(A)Investment Valuation: Equity securities listed on national securities
exchanges other than NASDAQ are valued at last sale price. If a last sale
price is not available, securities listed on national exchanges other
than NASDAQ are valued at the mean between the closing bid and closing
ask prices. NASDAQ National Market(R) and SmallCap/SM /securities are
valued at the NASDAQ Official Closing Price ("NOCP"). The NOCP is based
on the last traded price if it falls within the concurrent best bid and
ask prices and is normalized pursuant to NASDAQ's published procedures if
it falls outside this range. If an NOCP is not available for any such
security, the security is valued at the last sale price, or, if there
have been no sales that day, at the mean between the closing bid and
closing ask prices. Unlisted equity securities are valued at last sale
price, or when last sale prices are not available, at the last quoted bid
price. Debt securities (other than short-term obligations maturing in
sixty days or less) are valued on the basis of valuations furnished by a
pricing service which takes into account appropriate factors such as
institution-size trading in similar groups of securities, yield, quality,
coupon rate, maturity, type of issue, and other market data, without
exclusive reliance on quoted prices or exchange or over-the-counter
prices, since such valuations are believed to reflect more accurately the
fair value of the securities. Securities, if any, for which there are no
such valuations or quotations available, or for which the market
quotation is not reliable, are valued at fair value by management as
determined in good faith under guidelines established by the Trustees.
Short-term obligations maturing in sixty days or less are valued at
amortized cost, which approximates market value.
(B)Securities Transactions and Investment Income: Securities transactions
are recorded on a trade date basis. Realized gains and losses from
securities transactions are determined using the identified cost basis.
Interest income, including amortization of premiums and accretion of
discounts on bonds, is recognized on the accrual basis and dividend
income is recorded on ex-dividend date.
(C)Options Transactions: The Balanced Fund may utilize options to hedge or
protect from adverse movements in the market values of its portfolio
securities and to enhance return. The Equity Fund may utilize options to

GREEN CENTURY FUNDS NOTES TO FINANCIAL STATEMENTS
(unaudited) continued

hedge against possible increases in the value of securities which are
expected to be purchased by the Equity Fund or possible declines in the
value of securities which are expected to be sold by the Equity Fund. The
use of options may involve risks such as the possibility of illiquid
markets or imperfect correlation between the value of the option and the
underlying securities. The Funds may write put or call options. Premiums
received upon writing put or call options are recorded as an asset with a
corresponding liability which is subsequently adjusted to the current
market value of the option. Changes between the initial premiums received
and the current market value of the options are recorded as unrealized
gains or losses. When an option is closed, expired or exercised, a gain
or loss is realized and the liability is eliminated. The Funds continue
to bear the risk of adverse movements in the price of the underlying
assets during the period of the option, although any potential loss
during the period would be reduced by the amount of the option premium
received. As required by the Act, liquid securities are designated as
collateral in an amount equal to the market value of open options
contracts.
(D)Repurchase Agreements: The Funds may enter into repurchase agreements
with selected banks or broker-dealers that are deemed by the Funds'
adviser to be creditworthy pursuant to guidelines established by the
Board of Trustees. Each repurchase agreement is recorded at cost, which
approximates fair value. The Funds require that the market value of
collateral, represented by securities (primarily U.S. Government
securities), be sufficient to cover payments of interest and principal
and that the collateral be maintained in a segregated account with a
custodian bank in a manner sufficient to enable the Funds to obtain those
securities in the event of a default of the counterparty. In the event of
default or bankruptcy by the counterparty to the repurchase agreement,
retention of the collateral may be subject to legal proceedings.
(E)Distributions: Distributions to shareholders are recorded on the
ex-dividend date. The Funds declare and pay dividends of net investment
income, if any, semi-annually and distribute net realized capital gains,
if any, annually. The amount and character of income and net realized
gains to be distributed are determined in accordance with Federal income
tax rules and regulations, which may differ from U.S. generally accepted
accounting principles. To the extent that these differences are
attributable to permanent book and tax accounting differences, the
components of net assets have been adjusted.
(F)Federal Taxes: Each series of the Trust is treated as a separate entity
for Federal income tax purposes. Each Fund's policy is to comply with the
provisions of the Internal Revenue Code applicable to regulated
investment companies. Accordingly, no provisions for Federal income or
excise tax are necessary.
In July 2006, the Financial Accounting Standards Board (FASB) issued
Interpretation No. 48, "Accounting for Uncertainty in Income Taxes" (FIN
48). FIN 48 addresses the accounting for uncertainty in income taxes and
establishes for all entities, including pass-through entities such as the
Funds, a minimum threshold for financial statement recognition of the
benefit of positions taken in filing tax returns (including whether an
entity is taxable in a particular jurisdiction). The Funds recognize tax
benefits only if it is more likely than not that a tax position
(including the Funds' assertion that their income is exempt from tax)
will be sustained upon examination. The Funds adopted FIN 48 in fiscal
2008. The Funds had no material uncertain tax positions and have not
recorded a liability for unrecognized tax benefits as of January 31,
2008. Also, the Funds had recognized no interest and penalties related to
uncertain tax benefits in 2008. At January 31, 2008, the tax years 2005
through 2008 remain open to examination in the Funds' major tax
jurisdictions.
(G)Redemption Fee: A 2.00% redemption fee is retained by the Funds to
offset the effect of transaction costs and other expenses associated with
short-term investing. The fee is imposed on redemptions or exchanges of
shares held 60 days or less from their purchase date. For the six months
ended January 31, 2008, the Balanced Fund and Equity Fund received $193
and $643, respectively, in redemption fees. Redemption fees are recorded
as an adjustment to paid-in capital.

GREEN CENTURY FUNDS NOTES TO FINANCIAL STATEMENTS
(unaudited) continued

NOTE 2 -- Transactions With Affiliates
(A)Investment Adviser: Green Century Capital Management, Inc. ("Green
Century") is the adviser ("the Adviser") for the Funds. Green Century is
owned by Paradigm Partners. Green Century oversees the portfolio
management of the Funds on a day-to-day basis. The Balanced Fund pays
Green Century a fee, accrued daily and paid monthly, at an annual rate
equal to 0.65% of the Balanced Fund's average daily net assets. The
Equity Fund pays Green Century a fee, accrued daily and paid monthly, at
an annual rate of 0.25% of the Equity Fund's average daily net assets up
to but not including $100 million, 0.22% of average daily net assets
including $100 million up to but not including $500 million, 0.17% of
average daily net assets including $500 million up to but not including
$1 billion and 0.12% of average daily net assets equal to or in excess of
$1 billion.
(B)Subadvisers: Trillium Asset Management Corporation ("Trillium") is the
subadviser for the Balanced Fund. Trillium is paid a fee by the Adviser
at an annual rate of 0.40% on the first $30 million of average daily net
assets and 0.35% on average daily net assets in excess of $30 million for
its services. For the six months ended January 31, 2008, Green Century
accrued fees of $98,524 to Trillium. Mellon Equity Associates, LLP
("Mellon") is the subadviser for the Equity Fund. Mellon is paid a fee by
the Adviser the greater of $50,000 or 0.08% of the value of the average
daily net assets of the Fund up to but not including $100 million, 0.05%
of the average daily net assets of the Fund from and including $100
million up to but not including $500 million, 0.02% of the average daily
net assets of the Fund from and including $500 million up to but not
including $1 billion and 0.01% of the average daily net assets of the
Fund equal to or in excess of $1 billion for its services. For the six
months ended January 31, 2008, Green Century accrued fees of $25,137 to
Mellon.
(C)Administrator: Green Century is the administrator ("the Administrator")
of the Green Century Funds. Pursuant to the Administrative Services
Agreement, Green Century pays all the expenses of each Fund other than
the investment advisory fees; interest; taxes; brokerage costs and other
capital expenses; expenses of non-interested trustees (including counsel
fees) and any extraordinary expenses. The Balanced Fund pays Green
Century a fee at a rate such that immediately following any payment to
the Administrator, the total operating expenses of the Fund, on an annual
basis, do not exceed 1.38% of the Fund's average daily net assets. The
Equity Fund pays Green Century a fee at a rate such that immediately
following any payment to the Administrator, the total operating expenses
of the Fund, on an annual basis, do not exceed 0.95% of the Fund's
average daily net assets.
(D)Subadministrator: Pursuant to a Subadministrative Services Agreement
with the Administrator, UMB Fund Services, Inc. ("UMBFS") as
Subadministrator, is responsible for conducting certain day-to-day
administration of the Trust subject to the supervision and direction of
the Administrator. For the six months ended January 31, 2008, Green
Century accrued fees of $41,218 and $41,218 to UMBFS related to services
performed on behalf of the Balanced Fund and the Equity Fund,
respectively.
(E)Index Agreement: The Equity Fund invests in the securities of the
companies included in the Domini Index. The Domini Index is owned and
maintained by KLD Research and Analytics, Inc. ("KLD"). For the use of
the Index, KLD is paid a fee by the Adviser the greater of $50,000 or at
an annual rate of 0.10% on the first $500 million of average daily net
assets, 0.075% on average daily net assets on the next $500 million, and
0.05% on average daily net assets in excess of $1 billion. For the six
months ended January 31 2008, Green Century accrued fees of $25,137 to
KLD.

NOTE 3 -- Investment Transactions
The Balanced Fund's cost of purchases and proceeds from sales of securities,
other than short-term securities, aggregated $10,687,855 and $13,248,817,
respectively, for the six months ended January 31, 2008. The Equity Fund's cost
of purchases and proceeds from sales of securities, other than short-term
securities, aggregated $2,824,116 and $1,510,143, respectively.

GREEN CENTURY FUNDS NOTES TO FINANCIAL STATEMENTS
(unaudited) concluded

NOTE 4 -- Federal Income Tax Information
The tax basis of the components of distributable net earnings (deficit) at
July 31, 2007 were as follows:

BALANCED FUND EQUITY FUND
------------- -----------

Undistributed ordinary income......................................... $ 82,095 $ 49,322
Undistributed long-term capital gains................................. -- 1,920,596
------------ ----------
Tax accumulated earnings.............................................. 82,095 1,969,918
------------ ----------
Accumulated capital and other losses.................................. (11,955,622) --
Unrealized appreciation............................................... 3,125,588 1,281,896
------------ ----------
Distributable net earnings (deficit).................................. $ (8,747,939) $3,251,814
============ ==========

The Balanced Fund has an accumulated capital loss carryforward of $11,955,622
of which $2,585,392 expires in the year 2010 and $9,370,230 expires in the year
2011. To the extent that the Fund realizes future net capital gains, those
gains will be offset by any unused capital loss carryforwards. The Balanced
Fund and Equity Fund utilized $1,970,122 and $5,173,829, respectively, of its
capital loss carryforwards during the year ended July 31, 2007.

The tax character of distributions paid during the fiscal years ended July 31,
2007 and 2006 were as follows:

BALANCED FUND EQUITY FUND
--------------------------- ---------------------------
YEAR ENDED YEAR ENDED YEAR ENDED YEAR ENDED
JULY 31, 2007 JULY 31, 2006 JULY 31, 2007 JULY 31, 2006

Ordinary income....................................................... $612,601 $89,058 $335,455 $55,690
Long-term capital gains............................................... -- -- -- --

NOTE 5 -- Capital Share Transactions
Capital Share transactions for the Balanced Fund and the Equity Fund were as
follows:

BALANCED FUND
-----------------------------
SIX MONTHS ENDED YEAR ENDED
JANUARY 31, 2008 JULY 31, 2007

Shares sold........................................................... 124,395 278,696
Reinvestment of dividends............................................. 24,647 32,817
Shares redeemed....................................................... (194,077) (485,913)
-------- --------
(45,035) (174,400)
======== ========

EQUITY FUND
-----------------------------
SIX MONTHS ENDED YEAR ENDED
JANUARY 31, 2008 JULY 31, 2007

Shares sold........................................................... 171,425 430,260
Reinvestment of dividends............................................. 96,483 14,371
Shares redeemed....................................................... (128,448) (235,379)
-------- --------
139,460 209,252
======== ========

NOTE 6 -- New Accounting Pronouncement
In September 2006, the Financial Accounting Standards Board issued Statement of
Financial Accounting Standards No. 157, "Fair Value Measurements." The
Statement defines fair value, establishes a framework for measuring fair value
in generally accepted accounting principles ("GAAP"), and expands disclosures
about fair value measurements. The Statement establishes a fair value hierarchy
that distinguishes between (1) market participant assumptions developed based
on market data obtained from sources independent of the reporting entity
(observable inputs) and (2) the reporting entity's own assumptions about market
participant assumptions developed based on the best information available in
the circumstances (unobservable inputs). The Statement will be effective for
the Funds' financial statements issued for fiscal years beginning August 1,
2008. Management does not expect material impacts to the Funds' financial
statements from the application of the Statement to the Funds.

BOARD OF TRUSTEES' CONSIDERATION OF ADVISORY AND SUBADVISORY AGREEMENTS

The Board of Trustees of the Green Century Funds considered and approved the
continuance of two advisory and subadvisory agreements during the six months
ended January 31, 2008.

INVESTMENT ADVISORY AGREEMENT WITH GREEN CENTURY CAPITAL MANAGEMENT, INC.
At a meeting on September 28, 2007, the Board, including the Independent
Trustees, approved the continuance of an Investment Advisory Agreement between
the Trust, on behalf of the Balanced Fund, and Green Century Capital
Management, Inc. ("Green Century" or the "Adviser"). In connection with their
deliberations at the meeting, and at a separate executive session of the
Independent Trustees held on the same day, the Trustees considered, among other
things, information provided by Green Century regarding the investment
performance of the Balanced Fund, the total expenses of the Balanced Fund and
the advisory fee to be paid to Green Century, and the profitability to Green
Century of its advisory relationship to the Balanced Fund. The Independent
Trustees were advised by independent counsel in considering these materials and
the continuance of the Advisory Agreement. The Trustees considered all the
information provided to them by Green Century, including information provided
throughout the year. In approving the continuance of the Advisory Agreement,
the Board, including the Independent Trustees, did not identify any single
factor as determinative. Matters considered in connection with their approval
of the Advisory Agreement included the following.

Nature, Quality, and Extent of Services Performed. The Trustees considered the
scope and quality of the services performed for the Balanced Fund by the
Adviser, including the resources dedicated by the Adviser. The services
performed included the oversight and monitoring of the portfolio management and
performance of the Balanced Fund; monitoring the implementation of the Balanced
Fund's environmental screens; implementing the environmental policies of the
Funds by voting the Balanced Fund's shareholder proxies; and overall compliance
oversight provided by the Adviser. In addition, the Trustees considered the
administrative services provided by the Adviser to the Balanced Fund, including
the coordination of the activities of all of the Balanced Funds' other service
providers.

Based on its review of all of the services provided and to be provided, the
Trustees concluded that the nature, quality and extent of services provided by
the Adviser supported the continuance of the Advisory Agreement.

Costs of Services Provided and Profitability. The Trustees considered the
costs of the services provided to the Balanced Fund and the profitability and
fall-out benefits to the Adviser from its arrangement with the Balanced Fund.

The Trustees reviewed and considered an analysis of the advisory fee and total
expense ratio of the Balanced Fund and comparative data for over 7,000 mutual
funds presented in four categories: socially conscious funds, socially
conscious balanced funds, all balanced funds, and balanced funds of under $100
million in assets. The Trustees noted that, based on the information provided,
the advisory fee was higher than the average advisory fee for each of the four
categories. The Trustees considered that Green Century had reduced the advisory
fee by 10 basis points in 2006. The Trustees also noted that the total expense
ratio of the Balanced Fund was limited to 1.38% and that the total expense
ratio was in line with the average total expense ratio for each of the four
categories of comparison funds.

Green Century provided the Trustees with information prepared by the Adviser
relating to the profitability to Green Century of its advisory relationship to
the Balanced Fund. In that regard, the Trustees considered the subadvisory fees
and the other expenses incurred by the Adviser in providing advisory services
to the Balanced Fund. The Trustees also considered the fee received by the
Adviser for providing administrative services to the Balanced Fund and the
expenses incurred by the Adviser in providing those services. In evaluating the
Adviser's cost allocation methodology, the Trustees took into consideration
that the Adviser does not provide advisory or administrative services to other
mutual

funds or non-mutual fund clients other than the Green Century Equity Fund. The
Trustees also considered Green Century's non-profit ownership structure, its
cost structure and personnel needs, and its investment in shareholder advocacy
to further the Balanced Fund's stated objective of promoting greater corporate
environmental accountability. After reviewing the information described above,
the Trustees, including the Independent Trustees, concluded that the fees
specified in the Advisory Agreement, taking into account the costs of the
services provided by the Adviser and the profitability to the Adviser of its
relationship with the Balanced Fund, supported the continuance of the Advisory
Agreement.

Other Benefits. With respect to fall-out benefits, the Trustees considered
that neither Green Century nor any affiliate of Green Century receives any
brokerage fees, soft dollar benefits, liquidity rebates from electronic
communications networks or payments for order flow from the trades executed for
the Balanced Fund. The Trustees noted that Green Century benefits intangibly
from its relationship with the Balanced Fund due to the Funds' reputation as
the first family of no-load environmentally responsible mutual funds. Further,
pursuant to the Advisory Agreements, Green Century has reserved for itself the
rights to the names "Green Century Funds" and any similar names; thus, Green
Century may benefit in the future from developing other funds or investment
products with the Green Century brand. The Trustees concluded that the fall-out
benefits to be realized by Green Century were appropriate and supported the
continuance of the Advisory Agreement.

Investment Performance. The Trustees reviewed and considered information
regarding the investment performance of the Balanced Fund and comparative data
with respect to the performance of other funds designated by Morningstar to
have similar investment objectives as well as the Balanced Fund's performance
measured against the Lipper Balanced Fund Index, a broad-based balanced fund
market index. The Trustees noted that as of the period ended August 31, 2007,
the Balanced Fund's three- and ten-year average annual returns were similar to
those of the Lipper Balanced Fund Index, while the one-year return had
significantly underperformed and the five-year average annual return had
significantly outperformed the benchmark. The Trustees also considered the
performance information they had been provided throughout the year. After
considering all the factors deemed appropriate, the Trustees, including the
Independent Trustees, concluded that the performance of the Balanced Fund
supported the continuance of the Advisory Agreement.

Economies of Scale. The Trustees also considered whether economies of scale
could be realized by the Adviser as the Balanced Fund grew in asset size and
the extent to which such economies of scale were reflected in the level of fees
charged. They noted the relatively small size of the Balanced Fund and the
resultant difficulty for the Adviser to achieve meaningful economies of scale.
They considered that if the assets were to increase, the Balanced Fund could
have the opportunity to experience economies of scale as fixed costs would
become a smaller percentage of the Balanced Fund's assets and some of the
Balanced Fund's service providers' fees, as a percentage of the Balanced Fund's
assets, could decrease. The Trustees concluded that economies of scale could be
realized as the Balanced Fund grew and that if assets increased significantly
the Trustees would have opportunities to negotiate decreases in fees with the
Adviser.

Based on a review of all factors deemed relevant, the Trustees, including the
Independent Trustees, concluded that the Advisory Agreement should be continued
and that they would consider whether to renew it after a one-year period.

INVESTMENT SUBADVISORY AGREEMENT WITH TRILLIUM ASSET MANAGEMENT CORPORATION
Also at the meeting on September 28, 2007, the Board of Trustees of the
Balanced Fund, including a majority of the Independent Trustees, considered the
continuance of the subadvisory agreement between the Trust, on behalf of the
Balanced Fund, Green Century, and Trillium Asset Management Corporation
("Trillium") (the "Subadvisory Agreement"). In connection with their
deliberations at the meeting, and at a separate executive session of the
Independent Trustees held on the same day, the Trustees considered, among other
things, information provided by

Trillium regarding the investment performance of the Balanced Fund, the
subadvisory fees paid to Trillium, and the profitability to Trillium of its
subadvisory relationship to the Balanced Fund. The Independent Trustees were
advised by independent counsel in considering these materials and the
continuance of the Subadvisory Agreement. The Trustees considered all the
information provided to them by Trillium, including information provided
throughout the initial two-year term of the Subadvisory Agreement. In approving
the continuance of the Subadvisory Agreement, the Board, including the
Independent Trustees, did not identify any single factor as determinative.
Matters considered in connection with their approval of the Subadvisory
Agreement included the following.

Nature, Quality, and Extent of Services Performed. The Trustees noted that
under the terms of the Subadvisory Agreement, Trillium provided the day-to-day
portfolio management of the Balanced Fund, including determining asset and
sector allocation; conducting securities selection and discovery; researching
and analyzing environmental policies and practices of companies and
implementing the Balanced Fund's environmental screening criteria; managing
volatility, risk, and portfolio turnover; and investing the portfolio
consistent with the Balanced Fund's investment objective and policies. The
Trustees considered the professional expertise, tenure, and qualifications of
the portfolio management team and noted that Trillium was devoted exclusively
to environmentally and socially responsible investing and managed over $1
billion in assets. The Trustees also considered Trillium's compliance record as
well as the professional experience and responsiveness of Trillium's compliance
staff. The Trustees also considered Trillium's leadership in social and
environmental responsibility, including its shareholder advocacy efforts.

Based on its review of all of the services provided and to be provided, the
Trustees concluded that the nature, quality and extent of services provided by
Trillium supported the continuance of the Subadvisory Agreement.

Costs of Services Provided and Profitability. The Trustees considered that the
subadvisory fees paid by Green Century to Trillium under the Subadvisory
Agreement were 0.40% of the value of the average daily net assets of the
Balanced Fund up to $30 million, and 0.35% of the value of the average daily
net assets of the Balanced Fund in excess of $30 million. The Trustees reviewed
the subadvisory fees against comparative data for over 7,000 mutual funds
presented in three categories: socially conscious funds, all balanced funds,
and balanced funds of under $100 million in assets. The Trustees noted that,
based on the information provided, the subadvisory fees were higher than those
of all socially conscious funds and similar to those paid by all balanced funds
and balanced funds of under $100 million in assets. The Trustees also noted
that the subadvisory fees are paid by Green Century, and are not in addition to
the advisory fees paid to Green Century by shareholders.

In evaluating the profitability of the Subadvisory Agreement to Trillium, the
Trustees noted that based on information provided by Trillium, the relationship
was not profitable. The Trustees noted that Trillium stated that it would not
realize a fair entrepreneurial profit on the management of the Balanced Fund
until assets increase to $100 million. The Trustees considered the financial
resources Trillium dedicated and the other expenses Trillium incurred in
providing subadvisory services to the Balanced Fund, including startup costs
relating to the relationship, and additional personnel, legal, trading analysis
and compliance costs required in the context of providing subadvisory services
to a mutual fund. In considering the cost allocation methodology used by
Trillium, the Trustees took under consideration that Trillium does not provide
advisory or subadvisory services to other mutual fund clients. The Trustees
also considered Trillium's fee structure and noted, based on the information
provided, that the subadvisory fees were lower than the fees Trillium charges
its other institutional clients.

After reviewing the information described above, the Trustees concluded that
the fees specified in the Subadvisory Agreement, taking into account the nature
and quality of services provided and the costs of the services provided by
Trillium, supported the continuance of the Subadvisory Agreement.

Other Benefits. The Trustees evaluated potential other benefits Trillium may
realize from its relationship with the Balanced Fund. The Trustees considered
the brokerage practices of Trillium, including the soft dollar commissions that
were generated with respect to the Balanced Fund's portfolio transactions. The
Trustees considered that Trillium was not affiliated with a broker/dealer and
therefore no benefit would be realized by Trillium through transactions with
affiliated brokers. The Trustees also considered the reputational and other
advantages Trillium may gain from its relationship with the Balanced Fund. The
Trustees concluded that the benefits expected to be received by Trillium were
reasonable in the context of the relationship between Trillium and the Balanced
Fund, and supported the continuance of the Subadvisory Agreement.

Investment Performance. The Trustees reviewed and considered information
regarding the investment performance of the Balanced Fund and comparative data
with respect to performance of mutual funds with similar investment objectives
as well as other broad-based market indexes. The Trustees noted that as of the
period ended August 31, 2007, the Balanced Fund's one-year return had
significantly underperformed the Lipper Balanced Fund Index, as had the
Balanced Fund since Trillium became the Balanced Fund's Subadviser on
November 28, 2005. The Trustees also considered information and analysis
presented by Trillium regarding the underperformance. After considering all the
factors deemed appropriate, the Trustees concluded that the performance of the
Balanced Fund together with Trillium's investment process, philosophies and
experience in environmentally and socially responsible investing supported the
continuance of the Subadvisory Agreement.

Economies of Scale. The Trustees also considered whether economies of scale
would be realized by Trillium as the Balanced Fund grew in asset size and the
extent to which such economies of scale might be reflected in the subadvisory
fees. They noted the relatively small size of the Balanced Fund and considered
that if the assets were to increase, Trillium could have the opportunity to
experience economies of scale. They also noted that pursuant to the Subadvisory
Agreement, the subadvisory fees paid to Trillium by Green Century include a
breakpoint at $30 million, so that fees would decrease as assets in the
Balanced Fund increase. The Trustees concluded that economies of scale could be
realized as the Fund grew, and that the fee schedule as proposed was
appropriate, and supported the approval of the Subadvisory Agreement.

Based on a review of all factors deemed relevant, the Trustees, including the
Independent Trustees, concluded that the Subadvisory Agreement should be
continued and that they would consider whether to renew it after a one-year
period.

Semi-Annual Report

INVESTMENT ADVISER AND ADMINISTRATOR
Green Century Capital Management, Inc.
114 State Street
Boston, MA 02109
1-800-93-GREEN
www.greencentury.com
info@greencentury.com

INVESTMENT SUBADVISER (Balanced Fund)
Trillium Asset Management Corporation
711 Atlantic Avenue
Boston, MA 02111

INVESTMENT SUBADVISER (Equity Fund)
Mellon Equity Associates, LLP
500 Grant Street Suite 4200
Pittsburgh PA 15258

COUNSEL TO INDEPENDENT TRUSTEES OF THE FUNDS
Debevoise & Plimpton
555 13th Street, N.W.
Washington, DC 20004

SUBADMINISTRATOR and DISTRIBUTOR
UMB Fund Services, Inc. (Subadministrator)
UMB Distribution Services, LLC (Distributor)
803 West Michigan Street, Suite A
Milwaukee, WI 53233

CUSTODIAN
State Street Bank and Trust Company
200 Clarendon Street
Boston, MA 02116

TRANSFER AGENT
Unified Fund Services, Inc.
2960 North Meridian Street, Suite 300
Indianapolis, IN 46208

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
KPMG LLP
99 High Street
Boston, MA 02110
[LOGO] GREEN CENTURY FUNDS
January 31, 2008

Balanced Fund

- --------------------------------------------------------------------------------

Equity
Fund
[LOGO] GREEN CENTURY FUNDS
An investment for your future.

Printed on recycled paper with soy-based ink.

Item 2. Code of Ethics

Not applicable to semi-annual reports.

Item 3. Audit Committee Financial Expert

Not applicable to semi-annual reports.

Item 4. Principal Accountant Fees and Services

Not applicable to semi-annual reports.

Item 5. Audit Committee of Listed Registrants

Not applicable.

Item 6. Schedule of Investments

Included as part of the report to shareholders filed under item 1 of this Form
N-CSR

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 Trustees.

Item 11.Controls and Procedures

(a) Based on an evaluation of the disclosure controls and procedures (as
defined in Rule 30a-3(c) under the Investment Company Act of 1940, as
amended, the "Disclosure Controls") as of a date within 90 days of the
filing date (the "Filing Date") of this Form N-CSR (the "Report"), the
registrant's principal executive officer and principal financial officer
have concluded that the Disclosure Controls are effectively designed to
ensure that information that is required to be disclosed by the registrant
in the Report is recorded, processed, summarized and reported

within the time periods specified in the Securities and Exchange
Commission's rules and forms, including ensuring that information required
to be disclosed in the Report is accumulated and communicated to the
registrant's management, including the registrant's principal executive
officer and principal financial officer, as appropriate to allow timely
decisions regarding required disclosures.

(b)There were no changes in the registrant's internal controls over financial
reporting (as defined in Rule 30 a-3(d) under the Investment Company Act of
1940) that occurred during the second fiscal quarter of the period covered
by this report that have materially affected, or are reasonably likely to
materially affect, the registrant's internal control over financial
reporting.

Item 12.Exhibits

(a) (1) Not applicable.

(2) Certifications for each principal executive and principal financial
officer as required by Rule 30a-2(a) under the Investment Company Act
of 1940, as amended, (17 CFR 270.30a-2(a)) are filed herewith.

(b) Certifications required by Rule 30a-2 (b) under the Investment Company Act
of 1940, as amended, (17 CFR 270.30a-2 (b)) are filed herewith.

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.

Green Century Funds

/s/ Kristina A. Curtis
- --------------------------
Kristina A. Curtis
President
April 7, 2008

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.

/s/ Kristina A. Curtis
- -----------------------------------------
Kristina A. Curtis
President and Principal Executive Officer
April 7, 2008

/s/ Bernadette L. Buck
- -----------------------------------------
Bernadette L. Buck
Treasurer and Principal Financial Officer
April 7, 2008