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                                                             EXHIBIT 99.906.CERT

CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

Scott Eston, Chief Executive Officer of GMO Trust (the "Registrant"), certifies
to the best of his knowledge that:

1.   The Registrant's periodic report on Form N-CSR for the period ended August
     31, 2003 (the "Form N-CSR") fully complies with the requirements of section
     13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

2.   The information contained in the Form N-CSR fairly presents, in all
     material respects, the financial condition and results of operations of the
     Registrant.

        /s/ Scott Eston
        --------------------------------
        Scott Eston
        Chief Executive Officer

        Date   May 7, 2004
            ------------------


A signed original of this written statement required by Section 906 of the
Sarbanes-Oxley Act of 2002, or other document authenticating, acknowledging, or
otherwise adopting the signature that appears in typed form within the
electronic version of this written statement required by Section 906 has been
provided to the Registrant and will be retained by the Registrant and furnished
to the Securities and Exchange Commission (the "Commission") or its staff upon
request.

This certification is being furnished to the Commission solely pursuant to 18
U.S.C. Section 1350 and is not being filed as part of the Form N-CSR with the
Commission.

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CERTIFICATION PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

Susan Randall Harbert, Chief Financial Officer of GMO Trust (the "Registrant"),
certifies to the best of her knowledge that:

1.   The Registrant's periodic report on Form N-CSR for the period ended August
     31, 2003 (the "Form N-CSR") fully complies with the requirements of section
     13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and

2.   The information contained in the Form N-CSR fairly presents, in all
     material respects, the financial condition and results of operations of the
     Registrant.

        /s/ Susan Randall Harbert
        --------------------------------
        Susan Randall Harbert
        Chief Financial Officer

     Date   May 7, 2004
         ---------------------


A signed original of this written statement required by Section 906 of the
Sarbanes-Oxley Act of 2002, or other document authenticating, acknowledging, or
otherwise adopting the signature that appears in typed form within the
electronic version of this written statement required by Section 906 has been
provided to the Registrant and will be retained by the Registrant and furnished
to the Securities and Exchange Commission (the "Commission") or its staff upon
request.

This certification is being furnished to the Commission solely pursuant to 18
U.S.C. Section 1350 and is not being filed as part of the Form N-CSR with the
Commission.