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                                                                Exhibit 31.1

CERTIFICATIONS
I, Gerald A. Potthoff, certify that:

         1.   I have reviewed this quarterly report on Form 10-Q of
              Engineered Support Systems, Inc.;

         2.   Based on my knowledge, this quarterly report does not contain
              any untrue statements 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
              report;

         3.   Based on my knowledge, the financial statements, and other
              financial information included in this quarterly 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 officer 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 and procedures 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 quarterly 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; and

              c.  disclosed in this report any change in the registrant's
                  internal control over financial reporting that occurred
                  during the registrant's most recent 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 officer 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 or registrant's board of directors (or
              persons performing the equivalent functions):

              a.  all significant deficiencies and material weakness 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:  September 14, 2004



/s/  Gerald A. Potthoff
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Gerald A. Potthoff
Vice Chairman, Chief Executive Officer and President