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                                                              Exhibit 99.906CERT

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

David G. Booth, Principal Executive Officer, and Michael T. Scardina, Principal
Accounting Officer, of The DFA Investment Trust Company, a Delaware statutory
trust (the "Registrant"), each certify that:

    1.    The Registrant's periodic report on Form N-CSR for the period ended
          November 30, 2003 (the "Form N-CSR") fully complies with the
          requirements of Section 13(a) or Section 15(d) of the Securities
          Exchange Act of 1934, as amended, as applicable; 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.


By: /s/David G. Booth
    ------------------------
    David G. Booth
    Principal Executive Officer
    The DFA Investment Trust Company


Date:    2/3/04
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By: /s/ Michael T. Scardina
    ------------------------
    Michael T. Scardina
    Principal Accounting Officer
    The DFA Investment Trust Company

Date:    2/3/04
     -------------