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008 D060702 EH38YF
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008 D020703 NY
008 D030703 10048
008 A000704 SEI INVESTMENTS MANAGEMENT
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008 C000704 801-0000
008 D010704 OAKS
008 D020704 PA
008 D030704 19456
008 A000705 CAPITAL GUARDIAN TRUST COMPANY
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<PAGE> PAGE 21
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<PAGE> PAGE 22
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<PAGE> PAGE 23
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<PAGE> PAGE 24
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SIGNATURE MARK NAGLE
TITLE CONTROLLER
REPORT OF INDEPENDENT ACCOUNTANTS
To the Shareholders and Trustees of
SEI Institutional Investments Trust:
In planning and performing our audit of the financial
statements and financial highlights of SEI Institutional
Investments Trust for the year ended May 31,1999, we
considered its internal control, including control activities
for safeguarding securities, in order to determine our
auditing procedures for the purpose of expressing our
opinion on the financial statements and financial highlights
and to comply with the requirements of Form N-SAR, not to
provide assurance on internal control.
The management of SEI Institutional Investments Trust is
responsible for establishing and maintaining internal control.
In fulfilling this responsibility, estimates and judgments
by management are required to assess the expected benefits
and related costs of controls. Generally, controls that
are relevant to an audit pertain to the entity's objective
of preparing financial statements for external purposes
that are fairly presented in conformity with generally
accepted accounting principles. Those controls include
the safeguarding of assets against unauthorized acquisition,
use or disposition.
Because of inherent limitations in internal control,
errors or fraud may occur and not be detected. Also,
projection of any evaluation of internal control to future
periods is subject to the risk that it may become inadequate
because of changes in conditions or that the effectiveness
of the design and operation may deteriorate.
Our consideration of internal control would not necessarily
disclose all matters in internal control that might be
material weaknesses under standards established by the
American Institute of Certified Public Accountants. A
material weakness is a condition in which the design or
operation of one or more of the internal control components
does not reduce to a relatively low level the risk that
misstatements caused by errors or fraud in amounts that
would be material in relation to the financial statements
and financial highlights being audited may occur and not be
detected within a timely period by employees in the normal
course of performing their assigned functions. However,
we noted no matters involving internal control and its
operation, including controls over safeguarding securities,
that we consider to be material weaknesses as defined
above as of May 31, 1999.
This report is intended solely for the information and
use of management and Trustees of SEI Institutional
Investments Trust and the Securities and Exchange
Commission.
July 20, 1999
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