<PAGE> PAGE 1
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<PAGE> PAGE 4
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SIGNATURE MARK NAGLE
TITLE CONTROLLER
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</TABLE>
REPORT OF INDEPENDENT PUBLIC ACCOUNTANTS
To the Shareholders and
Board of Trustees of SEI Index Funds:
In planning and performing our audit of the financial
statements of SEI Index Funds for the year ended March
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
to comply with the requirements of Form N-SAR, not to
provide assurance on internal control.
The management of SEI Index Funds 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
March 31, 1999.
This report is intended solely for the information and
use of management, the Board of Trustees of SEI Index Funds,
and the Securities and Exchange Commission.
Arthur Anderson LLP
Philadelphia, Pennsylvania
May 3, 1999
