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Exhibit 99.Cert
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. (the "Registrant");
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-3(c) under the Investment Company Act of 1940, as
amended) and internal control over financial reporting (as defined in
Rule 30a-3(d) under the Investment Company Act of 1940, as amended) for
the Registrant and have:
a) designed such disclosure controls and procedures, or caused
such disclosure controls and procedures to be designed under
our supervision, 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) designed such internal control over financial reporting, or
caused such internal control over financial reporting to be
designed under our supervision, to provide reasonable
assurance regarding the reliability of financial reporting
and the preparation of financial statements for external
purposes in accordance with generally accepted accounting
principals;
c) evaluated the effectiveness of the Registrant's disclosure
controls and procedures and presented in this report our
conclusions about the effectiveness of the disclosure
controls and procedures, as of a date within 90 days prior
to the filing date of this report based on such evaluation;
and
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d) disclosed in this report any change in the Registrant's
internal control over financial reporting that occurred
during the second fiscal quarter of the period covered by
this report that has materially affected, or is reasonably
likely to materially affect, the Registrant's internal
control over financial reporting; and
5. The Registrant's other certifying officers and I have disclosed 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 and material weaknesses in the
design or operation of internal control over financial
reporting which are reasonably likely to adversely affect
the Registrant's ability to record, process, summarize, and
report financial information; 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 over financial reporting.
Date: February 3, 2006
By: /s/ David G. Booth
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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-3(c) under the Investment Company Act of 1940, as
amended) and internal control over financial reporting (as defined in
Rule 30a-3(d) under the Investment Company Act of 1940, as amended) for
the Registrant and have:
a) designed such disclosure controls and procedures, or caused
such disclosure controls and procedures to be designed under
our supervision, 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) designed such internal control over financial reporting, or
caused such internal control over financial reporting to be
designed under our supervision, to provide reasonable
assurance regarding the reliability of financial reporting
and the preparation of financial statements for external
purposes in accordance with generally accepted accounting
principals;
c) evaluated the effectiveness of the Registrant's disclosure
controls and procedures and presented in this report our
conclusions about the effectiveness of the disclosure
controls and procedures, as of a date within 90 days prior
to the filing date of this report based on such evaluation;
and
d) disclosed in this report any change in the Registrant's
internal control over financial reporting that occurred
during the second
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fiscal quarter of the period covered by this report that has
materially affected, or is reasonably likely to materially
affect, the Registrant's internal control over financial
reporting; and
5. The Registrant's other certifying officers and I have disclosed 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 and material weaknesses in the
design or operation of internal control over financial
reporting which are reasonably likely to adversely affect
the Registrant's ability to record, process, summarize, and
report financial information; 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 over financial reporting.
Date: February 3, 2006
By: /s/ Michael T. Scardina
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Michael T. Scardina
Principal Financial Officer
Dimensional Investment Group Inc.