EXHIBIT NO. EX-99.d.1.o.i

                        THE DFA INVESTMENT TRUST COMPANY

                       THE U.S. 9-10 SMALL COMPANY SERIES

                         INVESTMENT MANAGEMENT AGREEMENT
                               ADDENDUM NUMBER ONE

         THIS ADDENDUM made this 27th day of March, 2001, by and between THE DFA
INVESTMENT TRUST COMPANY, a Delaware business trust (the "Trust"), on behalf of:

                      "THE U.S. 9-10 SMALL COMPANY SERIES"

(the "Series"), a separate series of the Trust, and DIMENSIONAL FUND ADVISORS
INC., a Delaware corporation (the "Manager").

         WHEREAS, the Trust and the Manager have previously entered into an
Investment Management Agreement, dated November 28, 1997 (the "Investment
Management Agreement"), pursuant to which the Manager agreed to manage the
investment and reinvestment of the assets of the Series; and

         WHEREAS, the Manager has been informed by the Trust that the Series
desires to change its name;

         NOW, THEREFORE, in consideration of the terms and conditions
hereinafter set forth, it is hereby agreed as follows:

         1.   The name of the Series shall be changed from "The U.S. 9-10 Small
Company Series" to "The U.S. Micro Cap Series," and all references in the
Investment Management Agreement to "The U.S. 9-10 Small Company Series" shall be
changed to "The U.S. Micro Cap Series."

         2.   The effective date of this Addendum shall be March 29, 2001.

         3.   The parties hereby further agree that no other provisions of the
Investment Management Agreement are in any way modified by this Addendum, and
that all other provisions of the Investment Management Agreement remain in full
force and effect.

         IN WITNESS WHEREOF, the parties hereby have caused this Addendum to be
executed this 27th day of March, 2001.

THE DFA INVESTMENT TRUST                      DIMENSIONAL FUND ADVISORS
COMPANY                                       INC.


By: /s/ Michael T. Scardina                   By: /s/ Catherine L. Newell
    ---------------------------------------       -----------------------------
    Michael T. Scardina                           Catherine L. Newell
    Vice President, Chief Financial Officer       Vice President and Secretary
    and Treasurer

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