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                                                                    Exhibit 31.1

                                  CERTIFICATION

I, William C. Stone, certify that:

      1.    I have reviewed this annual report on Form 10-K, as amended,
            of SS&C Technologies, Inc.;

      2.    Based on my knowledge, this annual report as amended 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 as amended;

      3.    Based on my knowledge, the financial statements, and other financial
            information included in this annual report as amended, 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 annual report as amended;

      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 annual report as amended is being prepared;

                  b)    [Paragraph omitted in accordance with SEC transition
                        instructions contained in SEC Release 34-47986]

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

                  d)    Disclosed in this annual report as amended any change in
                        the registrant's internal control over financial
                        reporting that occurred during the registrant's most
                        recent fiscal quarter (the registrant's fourth fiscal
                        quarter in the case of an annual report) 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: April 21, 2004                /s/ William C. Stone

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