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<PAGE> PAGE 2
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SIGNATURE ANNA RODRIQUES
TITLE MANAGER
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
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<CIK> 0001011008
<NAME> STATE STREET NAVIGATOR SECURITIES LENDING PRIME PORT.
<S> <C>
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<PERIOD-END> DEC-31-1999
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<INVESTMENTS-AT-VALUE> 12,073,315,731
<RECEIVABLES> 98,818,506
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</TABLE>
Report of Independent Accountants
To the Board of Trustees and Shareholders of
State Street Navigator Securities Lending Trust
In planning and performing our audit of the financial statements of State
Street Navigator Securities Lending Prime Portfolio (the "Fund") for the
year ended December 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 the Company 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 controls may become
inadequate because of changes in conditions or that the effectiveness of
their 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 December 31, 1999.
This report is intended solely for the information and use of the Fund's
Board of Trustees and management, and the Securities and Exchange Commission
and is not intended to be and should not be used by anyone other than these
specified parties.
PricewaterhouseCoopers LLP
February 23, 2000
2
2
