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                                                             Exhibit 99.11(a)(1)

                                    GMO TRUST

                                 CODE OF ETHICS
                                       FOR
                         PRINCIPAL EXECUTIVE OFFICER AND
                           PRINCIPAL FINANCIAL OFFICER

I.   COVERED OFFICERS/PURPOSE OF THE CODE

     This code of ethics (the "Code") for GMO Trust (the "Trust") and each
series thereof constituting a separate investment portfolio (the "Funds")
applies to the Trust's Principal Executive Officer and Principal Financial
Officer (the "Covered Officers") as identified on Exhibit A. The Code is
intended to promote:

   - honest and ethical conduct, including the ethical handling of actual or
     apparent conflicts of interest between personal and professional
     relationships;

   - full, fair, accurate, timely and understandable disclosure in reports and
     documents that a registrant files with, or submits to, the SEC and in other
     public communications made by the Trust;

   - compliance with applicable laws and governmental rules and regulations;

   - the prompt internal reporting of violations of the Code to an appropriate
     person or persons identified in the Code; and

   - accountability for adherence to the Code.

     Each Covered Officer should adhere to high standards of business ethics and
should be sensitive to situations that may give rise to actual as well as
apparent conflicts of interest.

II.  COVERED OFFICERS SHOULD HANDLE ETHICALLY ACTUAL AND APPARENT CONFLICTS OF
     INTEREST

     OVERVIEW. A "conflict of interest" occurs when a Covered Officer's private
interest interferes with the interests of, or that Officer's service to, the
Trust. For example, a conflict of interest would arise if a Covered Officer, or
a member of his family, receives improper personal benefits as a result of that
Officer's position in the Trust.

     Although typically not presenting an opportunity for improper personal
benefit, conflicts arise from, or as a result of, the contractual relationship
between the Trust and Grantham, Mayo, Van Otterloo & Co. LLC ("GMO"), the
Trust's investment adviser, of which the Covered Officers are also members,
officers or employees. As a result, this Code recognizes that the Covered
Officers will, in the normal course of their duties (whether formally for the
Trust or GMO, or for both), be involved in establishing policies and
implementing decisions which will have different effects on GMO and the Trust.
The participation of the Covered Officers in such activities is inherent in the
contractual relationship between the Trust and GMO and is consistent with the
performance by the Covered Officers of their duties as officers of the Trust. In
addition, it is recognized by
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the trustees of the Trust (the "Trustees") that the Covered Officers may also be
officers or employees of one or more other investment companies covered by this
or other Codes. These types of conflicts are addressed by the Investment
Company Act, the Investment Advisers Act and other policies and procedures of
the Trust.

     Other conflicts of interest are covered by the Code, even if such conflicts
of interest are not subject to provisions in the Investment Company Act and the
Investment Advisers Act. In reading the following examples of conflicts of
interest under the Code, Covered Officers should keep in mind that such a list
cannot ever be exhaustive by covering every possible scenario. It follows that
the overarching principle - that the personal interest of a Covered Officer
should not be placed improperly before the interest of the Trust - should be the
guiding principle in all circumstances.

     Each Covered Officer must:

   - not use personal influence or personal relationships improperly to
     influence investment decisions or financial reporting by the Trust whereby
     the Covered Officer would benefit personally to the detriment of the Trust;

   - not cause the Trust to take action, or fail to take action, for the
     individual personal benefit of the Covered Officer rather than for the
     benefit of the Trust;

   - not use material non-public knowledge of portfolio transactions made or
     contemplated for the Trust to profit personally or cause others to profit,
     by the market effect of such transactions;

   - not retaliate against any employee or Covered Officer for reports of
     potential violations of law that are made in good faith.

     There are some conflict of interest situations that should always be
discussed with the Trust's Chief Legal Officer if material. Examples of these
include:

   - any outside business activity other than with GMO and its affiliates that
     detracts from an individual's ability to devote appropriate time and
     attention to his responsibilities with the Trust ;

   - service as a director on the board (or equivalent position) of any company;

   - the receipt of any non-nominal gifts in excess of the amount stated in the
     Trust's and GMO's Code of Ethics under Rule 17j-1 of the Investment Company
     Act;

   - the receipt of any entertainment from any company with which the Trust has
     current or prospective business dealings unless such entertainment is
     business-related, reasonable in cost, appropriate as to time and place,
     and not so frequent as to raise any question of impropriety;

   - any ownership interest in, or any consulting or employment relationship
     with, any of the Trust's service providers, other than GMO and its
     affiliates;

   - a direct or indirect financial interest in commissions, transaction charges
     or spreads paid by the Trust for effecting portfolio transactions or for
     selling or redeeming shares other than an interest arising from the Covered
     Officer's employment, such as compensation or equity ownership.

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III. DISCLOSURE

   - Each Covered Officer must be familiar with the disclosure requirements
     applicable to the Trust and the Funds' disclosure controls and procedures;

   - Each Covered Officer must not knowingly misrepresent, or cause others to
     misrepresent, facts about the Trust to others, whether within or outside
     the Trust, including to the Trustees and auditors, and to governmental
     regulators and self-regulatory organizations; and

   - It is the responsibility of each Covered Officer to promote compliance with
     the standards and restrictions imposed by applicable, laws, rules and
     regulations.

IV.  REPORTING AND ACCOUNTABILITY

     Each Covered Officer must:

   - upon adoption of the Code (or thereafter as applicable, upon becoming a
     Covered Officer), affirm in writing to the Trust that the Covered Officer
     has received, read, and understands the Code.

   - annually thereafter affirm to the Trust that the Covered Officer has
     complied with the requirements of the Code.

   - report at least annually affiliations and potential conflicts.

   - notify the Trust's Chief Legal Officer and the Chairman of the Trust's
     Audit Committee promptly if Covered Officer knows of any violation of this
     Code. Failure to do so is itself a violation of this Code.

     The Trust's Chief Legal Officer is responsible for applying this Code to
specific situations in which questions are presented under it and has the
authority to interpret this Code in any particular situation. However, any
approvals or waivers sought by any Covered Officer must be considered by the
Trust's Audit Committee.

     The Trust will follow these procedures in investigating and enforcing this
Code:

   - the Trust's Chief Legal Officer will take all appropriate action to
     investigate any violations and potential violations reported to him;

   - if, after such investigation, the Trust's Chief Legal Officer believes that
     no violation has occurred, the Chief Legal Officer is not required to take
     any further action; any matter the Trust's Chief Legal Officer believes is
     or may be a violation will be reported to the Trust's Audit Committee;

   - if the Audit Committee determines that a violation has occurred, it will
     inform and make a recommendation to the Trustees, which will consider
     appropriate action which may include review of, and appropriate
     modifications to, applicable policies and procedures; notification to
     appropriate personnel of GMO or its board; or a recommendation to dismiss
     the Covered Officer as an officer of the Trust; and

   - any changes to or waivers of this Code will, to the extent required, be
     disclosed as provided by SEC rules.

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V.   OTHER POLICIES AND PROCEDURES

     The Trust's and GMO's Code of Ethics under Rule 17j-1 under the Investment
Company Act and GMO's more detailed policies and procedures are separate
requirements applying to the Covered Officers and others, and are not part of
this Code. This Code does not, and is not intended to, repeat or replace these
programs and procedures.

VI.  AMENDMENTS

     This Code may not be amended except in written form, which is specifically
approved or ratified by a majority vote of the Trustees, including a majority of
independent Trustees.

VII. CONFIDENTIALITY

     All reports and records prepared or maintained pursuant to this Code will
be considered confidential and shall be maintained and protected accordingly.
Except as otherwise required by law or this Code, such matters shall not be
disclosed to anyone other than the Audit Committee, the Trustees, their
respective counsel, and GMO and its counsel.

VIII. INTERNAL USE

     The Code is intended solely for the internal use by the Trust and does not
constitute an admission, by or on behalf of any Trust, as to any fact,
circumstance, or legal conclusion and does not create any rights of third
parties.

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Approved: November 20, 2003

Amended:

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EXHIBIT A

Persons Covered by this Code of Ethics at November 20, 2003:

Scott Eston

Susan Randall Harbert

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EXHIBIT B

Acknowledgement of Receipt of Code

Section IV of the Code requires that each Covered Officer, upon adoption of the
Code, affirm in writing to the Trust that the Covered Officer has received,
read, and understands the Code. By executing this Exhibit B, the undersigned
hereby makes such affirmation.


                                    /s/ Scott Eston
                                    --------------------------------------------

                                    Name: Scott Eston

                                    Title:  Chief Executive Officer

                                    Date:   February 9, 2004
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                                    /s/ Susan Randall Harbert
                                    --------------------------------------------

                                    Name: Susan Randall Harbert

                                    Title:  Chief Financial Officer

                                    Date:   February 9, 2004
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