Bingham McCutchen LLP
                               150 Federal Street
                                Boston, MA 02110

December 21, 2005

VIA EDGAR

U.S. Securities and Exchange Commission
Division of Investment Management
100 F Street, NE
Washington, D.C.  20549
    Attn.: Mrs. Patricia Williams

        Re:     Green Century Funds
                File Nos. 33-41692 and 811-06351

Dear Mrs. Williams:

        This letter is in response to comments we received from you on December
12, 2005 regarding the preliminary letter to shareholders, overview of proxy
statement, notice of special meeting, proxy statement, exhibits and proxy card
(collectively, the "Proxy Statement") filed by Green Century Funds (the
"Registrant") with respect to its series, Green Century Balanced Fund (the
"Balanced Fund") and Green Century Equity Fund (the "Equity Fund" and
collectively with the Balanced Fund, "the Funds") with the Securities and
Exchange Commission (the "Commission").

        Below are the Staff's comments regarding the Proxy Statement and the
Registrant's responses thereto:

A. Proposal 2. Approval of New Investment Subadvisory Agreement for the Balanced
   Fund

Comment:    The Staff notes that the description of the subadvisory fee payable
            to Adams Harkness Asset Management by the Balanced Fund under the
            subadvisory agreement that was terminated on November 27, 2005 does
            not indicate a "null zone" in which the fee does not increase or
            decrease as  a result of any positive or negative changes in the
            Fund's performance.

Response:   The Balanced Fund paid to Adams Harkness Asset Management a base fee
            equal on an annual basis to 0.40% of the value of the average daily
            net assets of the Fund. As described in the Proxy Statement, the
            Base Fee did not increase or decrease unless the Balanced Fund's
            total return differed from the total return of the Lipper Directors'
            Analytical Data Balanced Fund Average (the "Index Total Return") by
            positive or negative 1.00%. In order to clarify the null zone in the
            subadvisory fee payable to Adams Harkness Asset Management, the
            Registrant has added the description: "Base Fee" to the line in the
            table with respect to the fee of 0.40% payable if the Fund's total
            return differed from the Index Total Return by negative 0.99% to
            positive 0.99%.




U.S. Securities and Exchange Commission
December 21, 2005
Page 2

B. Proposal 3. Approval of New Declaration of Trust for the Funds

1.Comment:  The Staff requests that the following proposed changes to the
            Declaration of the Trust for the Funds be presented as separate
            proposals:

               i. Reorganization of the Trust or any Fund or any Class of Shares
               ii. Future Amendments
               iii. Investment in Other Investment Companies
               iv. Redemption
               v. Dollar-Weighted Voting
               vi. Other Changes

  Response: The Registrant has revised the proxy statement to present the
            above-described proposed changes to the Declaration of Trust for the
            Funds as separate proposals.

2.Comment:  The Staff asked that the Registrant provide additional disclosure
            about the circumstances in which the Trustees may seek to specify
            additional conditions to the redemption of shares, consistent with
            the Investment Company Act of 1940, as amended (the "1940 Act").

  Response: The Registrant has added additional disclosure about the
            circumstances in which the Trustees may impose additional
            conditions to the redemption of shares, consistent with the 1940
            Act.

3.Comment:  The Staff requests that the section of the Proxy
            Statement discussing classes of shares, which explains that the
            proposal clarifies that the Trustees can divide shares of the
            Registrant or any Fund into one or more classes, include an
            explanation as to how the proposed new provisions compare to
            existing provisions in the existing Declaration of Trust.

  Response: The Registrant has added that the existing Declaration of Trust did
            not specifically address the Trustees' authority to establish
            classes of shares.

4.Comment:  Paragraph Number 1 of the "Other Changes" section of
            the Proxy Statement explains that the new Declaration of Trust
            would permit the Funds to enter into and amend investment
            advisory and subadvisory agreements without shareholder approval
            if permitted by applicable law. The Staff requests that the
            Registrant provide additional disclosure regarding the impact of
            this proposed change on shareholders.

  Response: The Registrant has added the requested disclosure.

5.Comment:  Paragraph Number 4 of the "Other Changes" section of
            the Proxy Statement explains that the new Declaration of Trust
            would permit the Trustees to invest Fund assets in all types of
            investments, including derivatives. The Staff requests that the
            Registrant provide risk disclosure regarding investments in
            derivatives.

  Response: The Registrant has made the requested disclosure.




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December 21, 2005
Page 3

6.Comment:  The Staff requests that the Registrant discuss why the Board
            approved the proposed changes to the Declaration of Trust discussed
            in Paragraph Numbers 3, 16, 17, 18 and 20 of the "Other Changes"
            section of the Proxy Statement.

  Response: The Registrant has added the requested disclosure.

7.Comment:  The Staff requests that the Registrant discuss why the
            Board approved the proposed changes to the Declaration of Trust
            discussed in Paragraph Number 19 of the "Other Changes" section
            of the Proxy Statement, which would provide that shareholders
            may not bring suit on behalf of a Fund or the Registrant without
            first requesting that the Trustees bring such suit, and that
            shareholders will not be entitled to participate in a derivative
            or class action on behalf of any Fund or the shareholders of any
            other Fund, and vice versa.

  Response: The Registrant notes that the discussion in Paragraph Number 19 of
            the "Other Changes" section of the Proxy Statement currently
            specifies that:

            "The effect of these changes may be to discourage suits brought
            by shareholders. Given that the Trustees have a fiduciary
            obligation to act on your behalf and in your best interests when
            evaluating whether to bring a suit on your behalf, the Trustees
            believe that the changes may only discourage frivolous suits
            that would cause the Funds to incur unnecessary costs."

            The Registrant respectfully submits that the current disclosure
            adequately explains why the Board approved the proposed change
            to the Declaration of Trust and that no additional discussion of
            the Board's reasoning is necessary.

C.Proposal Numbers 4 and 5: Approval of Changes to and the Elimination of
  Certain Fundamental Investment Policies for the Balanced Fund and the Equity
  Fund

1.Comment:  Proposal D. - Real Estate and Commodities. The Registrant proposes
            that the fundamental investment policy for each Fund regarding
            commodities or commodity contracts be separated from the fundamental
            investment policy regarding investment in real estate and real
            estate limited partnerships. The Staff notes that the proposed
            policy regarding commodities and commodity contracts would provide
            that the restriction does not apply to investments in futures
            contracts or options on futures contracts. The Staff requests that
            the Registrant provide risk disclosure regarding investments in
            futures and options.

  Response: The Registrant has added the requested disclosure.

2.Comment:  Proposal F. - Issuance of Senior Securities. The
            Registrant proposes that the fundamental investment policy
            concerning the issuance of senior securities be revised to state
            that the Balanced Fund and Equity Fund may not issue senior
            securities if such issuance is specifically prohibited by the
            1940 Act. The Staff contends that since the Funds do not issue
            senior securities, the statement in the discussion of this
            proposal that "minor technical changes are proposed to be made
            to the Equity Fund's existing fundamental policy regarding the
            issuance of senior securities that are not expected to have a
            material effect on the operations or management of the Equity
            Fund" is misleading.




U.S. Securities and Exchange Commission
December 21, 2005
Page 4

  Response: The Registrant has deleted the statement that "minor technical
            changes are proposed to be made to the Equity Fund's existing
            fundamental policy regarding the issuance of senior securities
            that are not expected to have a material effect on the
            operations or management of the Equity Fund" and revised the
            disclosure to describe the changes proposed in more detail.

3.Comment:  Proposal H. - Concentration. The Registrant proposes
            that the fundamental investment policy of each Fund restricting
            concentration in any one industry be amended to clarify that all
            or any portion of the assets of each Fund may be invested in one
            or more investment companies. The Staff notes that the Equity
            Fund is a feeder fund that invests all of its assets in a master
            fund, and requests that the Registrant explain how the Equity
            Fund looks through to the investments of the master fund for
            purposes of determining industry concentration.

  Response: The Registrant has revised the disclosure to clarify that the
            proposed concentration policy for the Equity Fund will be the
            same as the concentration policy currently in place for the
            master fund in which the Equity Fund invests.

4.Comment:  Proposal K. - Diversification. The Registrant proposes that the
            fundamental investment policy that restricts the Equity Fund, with
            respect to 75% of its assets, from investing more than 5% of its
            assets in any one company be eliminated, and replaced with two
            non-fundamental policies. The Staff requests that the Registrant
            explain in its response to the Staff how the proposed change from a
            fundamental to a non-fundamental policy is consistent with Section
            13a-1 of the 1940 Act, which provides that a registered investment
            company may not change its subclassification from a diversified to a
            non-diversified company unless authorized by shareholder vote.

  Response: As a diversified investment company, each Fund must comply with the
            diversification requirements of the 1940 Act unless it changes its
            classification to non-diversified.  The Registrant is not changing
            the status of either Fund as a diversified company without
            shareholder approval. Each Fund remains subject to Section 13a-1 of
            the 1940 Act (which requires a Fund to obtain the approval of
            shareholders to change its subclassification from a diversified to a
            non-diversified company). The proposed change of the Funds'
            fundamental policy regarding diversification to a non-fundamental
            policy does not mean that the Funds do not still need to comply with
            Section 13a-1.

D. Part 4. Discussion of Annual Report

Comment:    The discussion of the availability of the Funds' Annual Report
            is placed at the end of the proxy statement. The Proxy Rules
            require that the discussion of the availability of the Funds'
            Annual Report be placed in a prominent position in the proxy
            statement. The Staff interprets this requirement to mean that
            the discussion of the availability of the Funds' Annual Report
            must be placed near the front of the proxy statement, and
            requests that the Registrant place the discussion of the
            availability of the Funds' Annual Report near the front of the
            proxy statement.




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December 21, 2005
Page 5

Response:   The Registrant has moved the discussion of the availability of
            the Funds' Annual Report to the first page of the Proxy
            Statement, immediately after the Overview of Proxy Statement and
            Notice of Special Meeting.

                                   * * * * * *

        We hope that this letter addresses your comments with respect to the
Registrant's preliminary Proxy Statement. Please note that attached is a letter
from the Registrant to the Commission that includes certain "Tandy"
acknowledgments. If you should have any further questions, please do not
hesitate to contact me at 617-951-8760.

                                        Sincerely,

                                        /s/ Toby R. Serkin
                                        Toby R. Serkin