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<PAGE> PAGE 2
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<PAGE> PAGE 3
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SIGNATURE BARRY FINK
TITLE VICE PRESIDENT
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Morgan Stanley Dean Witter Insured Municipal Securities
</LEGEND>
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> OCT-31-1999
<PERIOD-END> OCT-31-1999
<INVESTMENTS-AT-COST> 121,621,489
<INVESTMENTS-AT-VALUE> 123,884,483
<RECEIVABLES> 2,568,942
<ASSETS-OTHER> 44,583
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 126,498,008
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> (217,022)
<TOTAL-LIABILITIES> (217,022)
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 123,478,437
<SHARES-COMMON-STOCK> 8,650,213
<SHARES-COMMON-PRIOR> 8,831,513
<ACCUMULATED-NII-CURRENT> 670,434
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (130,879)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 2,262,994
<NET-ASSETS> 126,280,986
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 7,537,810
<OTHER-INCOME> 0
<EXPENSES-NET> (656,630)
<NET-INVESTMENT-INCOME> 6,881,180
<REALIZED-GAINS-CURRENT> (130,867)
<APPREC-INCREASE-CURRENT> (11,659,790)
<NET-CHANGE-FROM-OPS> (4,909,477)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (6,859,987)
<DISTRIBUTIONS-OF-GAINS> (1,642,618)
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 0
<NUMBER-OF-SHARES-REDEEMED> (181,300)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> (15,851,863)
<ACCUMULATED-NII-PRIOR> 649,241
<ACCUMULATED-GAINS-PRIOR> 1,642,606
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> (477,700)
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> (664,283)
<AVERAGE-NET-ASSETS> 136,111,677
<PER-SHARE-NAV-BEGIN> 16.09
<PER-SHARE-NII> 0.78
<PER-SHARE-GAIN-APPREC> (1.30)
<PER-SHARE-DIVIDEND> (0.78)
<PER-SHARE-DISTRIBUTIONS> (0.19)
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 14.60
<EXPENSE-RATIO> 0.49
</TABLE>
To the Shareholders and Board of Directors of
XYZ Fund
(2)
Report of Independent Accountants
To the Shareholders and Trustees of
Morgan Stanley Dean Witter Insured Municipal Securities
In planning and performing our audit of the financial statements
of Morgan Stanley Dean Witter Insured Municipal Securities (the
"Trust") for the year ended October 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 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 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 October 31, 1999.
This report is intended solely for the information and use of
the Trustees, 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.
December 8, 1999
Item 77Q2 Exhibit
Fund: Morgan Stanley Dean Witter Insured Municipal
Securities
Section 16(a) Beneficial Ownership Reporting Compliance
The following persons are "reporting persons" under Section
16 of the Securities Exchange Act of 1934 and had not
previously filed an "Initial Statement of Beneficial
Ownership of Securities" on Form 3:
Mitchell M. Merin
Ronald E. Robison
Joseph J. McAlinden
Wayne E. Hedien
Barry Fink
Thomas F. Caloia
None of the above reporting persons has ever held any shares
of the Fund.
