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                                                                    Exhibit 31.1

                                  CERTIFICATION

I, William C. Stone, certify that:

      1.    I have reviewed this quarterly report on Form 10-Q of SS&C
            Technologies, Inc.;

      2.    Based on my knowledge, this quarterly 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 quarterly 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 quarterly 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)) and internal
            control over financial reporting (as defined in Exchange Act Rules
            13a-15(f) and 15d-15(f)) 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)    Designed such internal control over financial reporting, or
                    caused such internal control over financial reporting to be
                    designed under our supervision, to provide reasonable
                    assurance regarding the reliability of financial reporting
                    and the preparation of financial statements for external
                    purposes in accordance with generally accepted accounting
                    principles;

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

              d)    Disclosed in this quarterly 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 of the 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: August 8, 2005                         /s/ William C. Stone

                                             William C. Stone
                                             Chief Executive Officer and
                                             Chairman of the Board of Directors
                                             (Principal Executive Officer)