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CERTIFICATION PURSUANT TO SECTION 302 OF
THE SARBANES-OXLEY ACT OF 2002
I, David G. Booth, certify that:
1. I have reviewed this report on Form N-CSR of Dimensional Investment Group
Inc.;
2. Based on my knowledge, this report does not contain any untrue statement of
a material fact or omit to state a material fact necessary to make the
statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this
report;
3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material
respects the financial condition, results of operations, changes in net
assets, and cash flows (if the financial statements are required to include
a statement of cash flows) of the registrant as of, and for, the periods
presented in this report;
4. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined
in Rule 30a-2(c) under the Investment Company Act of 1940, as amended) for
the registrant and have:
a) designed such disclosure controls and procedures to
ensure that material information relating to the
registrant, including its consolidated subsidiaries, is
made known to us by others within those entities,
particularly during the period in which this report is
being prepared;
b) evaluated the effectiveness of the registrant's
disclosure controls and procedures as of a date within
90 days prior to the filing date of this report (the
"Evaluation Date"); and
c) presented in this report our conclusions about the
effectiveness of the disclosure controls and procedures
based on our evaluation as of the Evaluation Date;
5. The registrant's other certifying officers and I have disclosed, based on
our most recent evaluation, to the registrant's auditors and the audit
committee of the registrant's board of directors (or persons performing the
equivalent functions):
a) all significant deficiencies in the design or operation
of internal controls which could adversely affect the
registrant's ability to
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record, process, summarize, and report financial data
and have identified for the registrant's auditors any
material weaknesses in internal controls; and
b) any fraud, whether or not material, that involves
management or other employees who have a significant
role in the registrant's internal controls; and
6. The registrant's other certifying officers and I have indicated in this
report whether or not there were significant changes in internal controls
or in other factors that could significantly affect internal controls
subsequent to the date of our most recent evaluation, including any
corrective actions with regard to significant deficiencies any material
weaknesses.
Date: 8/5/03
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By: /s/ David G. Booth
---------------------------------
David G. Booth
Principal Executive Officer
Dimensional Investment Group Inc.
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CERTIFICATION PURSUANT TO SECTION 302 OF
THE SARBANES-OXLEY ACT OF 2002
I, Michael T. Scardina, certify that:
1. I have reviewed this report on Form N-CSR of Dimensional Investment Group
Inc.;
2. Based on my knowledge, this report does not contain any untrue statement of
a material fact or omit to state a material fact necessary to make the
statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this
report;
3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material
respects the financial condition, results of operations, changes in net
assets, and cash flows (if the financial statements are required to include
a statement of cash flows) of the registrant as of, and for, the periods
presented in this report;
4. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined
in Rule 30a-2(c) under the Investment Company Act of 1940, as amended) for
the registrant and have:
a) designed such disclosure controls and procedures to
ensure that material information relating to the
registrant, including its consolidated subsidiaries, is
made known to us by others within those entities,
particularly during the period in which this report is
being prepared;
b) evaluated the effectiveness of the registrant's
disclosure controls and procedures as of a date within
90 days prior to the filing date of this report (the
"Evaluation Date"); and
c) presented in this report our conclusions about the
effectiveness of the disclosure controls and procedures
based on our evaluation as of the Evaluation Date;
5. The registrant's other certifying officers and I have disclosed, based on
our most recent evaluation, to the registrant's auditors and the audit
committee of the registrant's board of directors (or persons performing the
equivalent functions):
a) all significant deficiencies in the design or operation
of internal controls which could adversely affect the
registrant's ability to
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record, process, summarize, and report financial data
and have identified for the registrant's auditors any
material weaknesses in internal controls; and
b) any fraud, whether or not material, that involves
management or other employees who have a significant
role in the registrant's internal controls; and
6. The registrant's other certifying officers and I have indicated in this
report whether or not there were significant changes in internal controls
or in other factors that could significantly affect internal controls
subsequent to the date of our most recent evaluation, including any
corrective actions with regard to significant deficiencies any material
weaknesses.
Date: 8/7/03
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By: /s/ Michael T. Scardina
---------------------------------
Michael T. Scardina
Principal Financial Officer
Dimensional Investment Group Inc.