Exhibit No. EX-99.h.4.l


                                 FEE WAIVER AND
                          EXPENSE ASSUMPTION AGREEMENT

     FEE WAIVER AND EXPENSE  ASSUMPTION  AGREEMENT,  effective as of __________,
2008, between DFA Investment  Dimensions Group Inc., a Maryland corporation (the
"Fund"),  on behalf of International  Vector Equity Portfolio (the "Portfolio"),
and   Dimensional   Fund   Advisors   LP,   a   Delaware   limited   partnership
("Dimensional").

     WHEREAS, Dimensional has entered into an Investment Advisory Agreement with
the Fund, on behalf of the  Portfolio,  pursuant to which  Dimensional  provides
investment  management services for the Portfolio,  and for which Dimensional is
compensated based on the average net assets of such Portfolio; and

     WHEREAS,  the Fund and  Dimensional  have determined that it is appropriate
and in the best  interests of the  Portfolio and its  shareholders  to limit the
expenses of the Portfolio;

     NOW, THEREFORE, the parties hereto agree as follows:

     1.   Fee Waiver and Expense  Assumption by Dimensional.  Dimensional agrees
          to waive  all or a portion  of its  management  fee and to assume  the
          expenses  of the  Portfolio  to the  extent  necessary  to  limit  the
          Portfolio's   ordinary  operating  expenses  (not  including  expenses
          incurrent  through  an  investment  in  other  investment   companies)
          ("Portfolio  Expenses") to 0.60% of the Portfolio's average net assets
          on an annualized basis (the "Expense Limitation Amount").

     2.   Duty to Reimburse Dimensional. If, at any time, the Portfolio Expenses
          are less than  Portfolio's  Expense  Limitation  Amount,  the Fund, on
          behalf of the  Portfolio,  shall  reimburse  Dimensional  for any fees
          previously  waived and/or  expenses  previously  assumed to the extent
          that such  reimbursement  will not cause  the  Portfolio's  annualized
          Portfolio  Expenses  to  exceed  the  Portfolio's  Expense  Limitation
          Amount.  There shall be no  obligation  of the Fund,  on behalf of the
          Portfolio,  to  reimburse  Dimensional  for fees  waived  or  expenses
          previously assumed by Dimensional more than thirty-six months prior to
          the date of any such reimbursement.

     3.   Assignment.   No  assignment  of  this  Agreement  shall  be  made  by
          Dimensional without the prior consent of the Fund.

     4.   Duration and  Termination.  This  Agreement  shall  continue in effect
          until  April 1, 2009,  and shall  continue in effect from year to year
          thereafter,  unless  and until the Fund or  Dimensional  notifies  the
          other party to the Agreement, at least thirty days prior to the end of
          the one-year  period for the Portfolio,  of its intention to terminate
          the Agreement.  This Agreement shall automatically  terminate upon the
          termination of the Investment Advisory Agreement for the Portfolio.

     IN WITNESS  WHEREOF,  the parties hereto have executed this Agreement as of
the date first written above.

DIMENSIONAL FUND ADVISORS LP             DFA INVESTMENT DIMENSIONS GROUP INC.

By: DIMENSIONAL HOLDINGS INC.,
      General Partner

By:  ___________________________      By: ____________________________
Name:  _________________________      Name:  _________________________
Title: _________________________      Title: _________________________