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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, 2005 (the "Report") 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 Report 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: February 3, 2006


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

Date: February 3, 2006