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                                                                   EXHIBIT 31.2

I, James J. Reilly, certify that:

1.    I have reviewed this annual report on Form 10-K of Innovative Solutions
      and Support, Inc.;

2.    Based on my knowledge, this annual report does not contain any untrue
      statement of a material fact or omit to state a material fact necessary to
      make the statements made, in light of the circumstances under which such
      statements were made, not misleading with respect to the period covered by
      this annual report;

3.    Based on my knowledge, the financial statements, and other financial
      information included in this annual report, fairly present in all material
      respects the financial condition, results of operations and cash flows of
      the registrant as of, and for, the periods presented in this report;

4.    The registrant's other certifying officers and I are responsible for
      establishing and maintaining disclosure controls and procedures (as
      defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant
      and have:

        a)   Designed such disclosure controls and procedures or caused such
             disclosure controls to be designed under our supervision, to ensure
             that material information relating to the registrant, including its
             consolidated subsidiaries, is made known to us by others within
             those entities, particularly during the period in which this annual
             report is being prepared;

        b)   Evaluated the effectiveness of the registrant's disclosure controls
             and procedures and presented in this report our conclusions about
             the effectiveness of the disclosure controls and procedures, as of
             the end of the period covered by this report based on such
             evaluation;

        c)   Disclosed in this report any change in the registrant's internal
             control over financial reporting that occurred during the
             registrant's fourth fiscal quarter that has materially affected, or
             is reasonably likely to materially affect, the registrant's
             internal control over financial reporting; and

5.    The registrant's other certifying officers and I have disclosed, based on
      our most recent evaluation of internal control over financial reporting,
      to the registrant's auditors and the audit committee of registrant's board
      of directors (or persons performing the equivalent functions);

        a)   All significant deficiencies and material weaknesses in the design
             or operation of internal control over financial reporting which are
             reasonably likely to adversely affect the registrant's ability to
             record, process, summarize and report financial information; and

        b)   Any fraud, whether or not material, that involves management or
             other employees who have a significant role in the registrant's
             internal control over financial reporting.

Date:    December 6, 2004

/s/    JAMES J. REILLY
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James J. Reilly
Chief Financial Officer