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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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<PAGE> PAGE 25
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<PAGE> PAGE 26
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<PAGE> PAGE 28
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<PAGE> PAGE 29
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<PAGE> PAGE 30
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<PAGE> PAGE 31
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<PAGE> PAGE 32
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<PAGE> PAGE 33
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<PAGE> PAGE 34
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<PAGE> PAGE 35
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<PAGE> PAGE 36
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SIGNATURE MARK NAGLE
TITLE CONTROLLER
Report of Independent Accountants
To the Board of Trustees of
SEI Institutional Managed Trust:
In planning and performing our audit of the financial statements
of SEI Institutional Managed Trust (the "Trust"), consisting of
the Large Cap Value, Large Cap Growth, Tax managed Large
Cap, Small Cap Value, Small Cap Growth, Mid-Cap, Capital
Appreciation, Equity Income, Balanced, Core Fixed Income and
High Yield Bond Funds, for the year ended September 30, 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 to comply with the requirements of Form N-SAR, not to provide
assurance on internal control.
The management of the 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 error or fraud in amounts that would be material in
relation to the financial statements 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 for safeguarding securities that we consider to be material
weaknesses as defined above as of September 30, 1999.
This report is intended solely for the information and use of
management, the Board of Trustees of the Trust and the
Securities and Exchange Commission.
November 24, 1999
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<NAME> SEI INSTITUTIONAL MANAGED TRUST
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<PERIOD-START> OCT-01-1998
<PERIOD-END> SEP-30-1999
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<SHARES-COMMON-STOCK> 91918
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<NAME> SEI INSTITUTIONAL MANAGED TRUST
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