<PAGE>
DFA INVESTMENT DIMENSIONS GROUP INC.
SUPPLEMENT TO PROSPECTUS DATED MARCH 28, 1997
The prospectus of DFA Investment Dimensions Group Inc. (the "Fund") is revised
as follows:
ALL PORTFOLIOS
Effective August 1, 1997, the expenses of the Fund which are not allocable
to a particular Portfolio are to be borne by each Portfolio on the basis of its
relative net assets. Similarly, the expenses of The DFA Investment Trust
Company (the "Trust") which are not allocable to a particular Series are to be
borne by each Series on the basis of its relative net assets.
ENHANCED U.S. LARGE COMPANY PORTFOLIO
Effective August 1, 1997, Dimensional Fund Advisors Inc. (the "Advisor")
has agreed to waive its fee under the administration agreement to the extent
necessary to reduce the direct and indirect cumulative annual expenses of the
Enhanced U.S. Large Company Portfolio to not more than 0.45% of average net
assets of the Portfolio on an annualized basis; the Portfolio's direct and
indirect cumulative annual expenses may exceed 0.45% of its average net assets
on an annualized basis notwithstanding this fee waiver. This arrangement does
not extend to the fees of the Enhanced U.S. Large Company Series of the Trust.
The Advisor retains the right in its sole discretion to modify or eliminate this
fee waiver in the future.
DFA TWO-YEAR CORPORATE FIXED INCOME PORTFOLIO
DFA TWO-YEAR GOVERNMENT PORTFOLIO
The Fund is not accepting purchase orders for shares of DFA Two-Year
Corporate Fixed Income Portfolio and DFA Two-Year Government Portfolio.
PACIFIC RIM SMALL COMPANY PORTFOLIO
JAPANESE SMALL COMPANY PORTFOLIO
Effective August 1, 1997, the Advisor pays DFA Australia Limited (formerly
DFA Australia Ltd.) ("DFA Australia") $13,000 per year for the sub-advisory
services DFA Australia provides to the Advisor with respect to the Pacific Rim
Small Company Series and the Japanese Small Company Series.
DFA INTERNATIONAL SMALL CAP VALUE PORTFOLIO
LARGE CAP INTERNATIONAL PORTFOLIO
RWB/DFA INTERNATIONAL HIGH BOOK TO MARKET PORTFOLIO
EMERGING MARKETS PORTFOLIO
EMERGING MARKETS SMALL CAP PORTFOLIO
Effective July 18, 1997, the Advisor has entered into a Consulting Services
Agreement with Dimensional Fund Advisors Ltd. ("DFAL") and DFA Australia,
respectively. Pursuant to the terms of each Consulting Services Agreement, DFAL
and DFA Australia provide certain trading and administrative services to the
Advisor with respect to DFA International Small Cap Value Portfolio, Large Cap
International Portfolio, DFA International Value Series, Emerging Markets Series
and Emerging Markets Small Cap Series.
<PAGE>
U.S. SMALL CAP VALUE PORTFOLIO
Effective August 1, 1997, the U.S. Small Cap Value Portfolio changed its
name to U.S. 6-10 Value Portfolio and the U.S. Small Cap Value Series changed
its name to U.S. 6-10 Value Series.
THE DATE OF THIS SUPPLEMENT IS AUGUST 1, 1997.
-2-
<PAGE>
DFA INVESTMENT DIMENSIONS GROUP INC.
SUPPLEMENT TO THE PROSPECTUS DATED MARCH 28, 1997
VA SMALL VALUE PORTFOLIO
VA LARGE VALUE PORTFOLIO
VA INTERNATIONAL VALUE PORTFOLIO
VA INTERNATIONAL SMALL PORTFOLIO
VA SHORT-TERM FIXED PORTFOLIO
VA GLOBAL BOND PORTFOLIO
The prospectus of DFA Investment Dimensions Group Inc. for the funds listed
above is revised as follows:
ALL PORTFOLIOS
Effective August 1, 1997, the expenses of DFA Investment Dimensions Group
Inc. which are not allocable to a particular Portfolio are to be borne by each
Portfolio on the basis of its relative net assets.
VA INTERNATIONAL SMALL PORTFOLIO
Effective August 1, 1997, the Advisor pays DFA Australia Limited (formerly
DFA Australia Ltd.) ("DFA Australia") $13,000 per year for the sub-advisory
services it provides to Dimensional Fund Advisors Inc. (the "Advisor") with
respect to the VA International Small Portfolio.
VA INTERNATIONAL VALUE PORTFOLIO
Effective July 18, 1997, the Advisor has entered into a Consulting Services
Agreement with Dimensional Fund Advisors Ltd. ("DFAL") and DFA Australia whereby
DFAL and DFA Australia each provide certain trading and administrative services
to the Advisor with respect to the VA International Value Portfolio.
THE DATE OF THIS SUPPLEMENT IS AUGUST 1, 1997.