<PAGE> PAGE 1
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<PAGE> PAGE 2
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<PAGE> PAGE 9
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SIGNATURE PAUL SCHUBERT
TITLE TREASURER
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
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</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 000080403
<NAME> PAINEWEBBER MASTER SERIES, INC.
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</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 000080403
<NAME> PAINEWEBBER MASTER SERIES, INC.
<SERIES>
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<NAME> PAINEWEBBER MONEY MARKET FUND-CLASS C
<MULTIPLIER> 1,000
<S> <C>
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</TABLE>
April 17, 1998
To the Shareholders and Board of Directors of PaineWebber Money Market Fund
In planning and performing our audit of the financial statements of PaineWebber
Money Market Fund (the "Fund") for the year ended February 28, 1998, 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 Fund 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 February 28, 1998.
This report is intended solely for the information and use of management and
the Board of Directors of the Fund and the Securities and Exchange Commission.
PRICE WATERHOUSE LLP
