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SIGNATURE JUAN RODRIGUEZ
TITLE ASSISTANT CONTROLLER
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000897513
<NAME> ACM MUNICIPAL SECURITIES INCOME FUND, INC.
<S> <C>
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<PERIOD-END> OCT-31-1997
<INVESTMENTS-AT-COST> 231,079,143
<INVESTMENTS-AT-VALUE> 243,015,446
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0
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</TABLE>
Report of Independent Auditors
To the Shareholders and Board of Directors of
ACM Municipal Securities Income Fund, Inc.
In planning and performing our audit of the
financial statements of ACM Municipal Securities
Income Fund, Inc. for the year ended October 31,
1997, 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 the internal control.
The management of ACM Municipal Securities Income
Fund, Inc. 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 irregularities 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 the internal control would
not necessarily disclose all matters in the
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 errors or irregularities
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 the internal control and its operation,
including controls for safeguarding securities,
that we consider to be material weaknesses as
defined above at October 31, 1997.
This report is intended solely for the information
and use of the board of directors and management
of ACM Municipal Securities Income Fund, Inc. and
the Securities and Exchange Commission.
ERNST & YOUNG
LLP
New York, New York
December 4, 1997
