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                                                                    Exhibit 31.1

         I, A. Bronson Thayer, certify, that:

         1.       I have reviewed this quarterly report on Form 10-QSB of
                  Florida Business BancGroup, Inc.;

         2.       Based on my knowledge, this 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 report;

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

         4.       The small business issuer'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 small business issuer 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 small business
                           issuer, including its consolidated subsidiaries, is
                           made known to us by others within those entities,
                           particularly during the period in which this report
                           is being prepared;

                  (b)      Evaluated the effectiveness of the small business
                           issuer'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 small
                           business issuer's internal control over financial
                           reporting that occurred during the small business
                           issuer's most recent fiscal quarter (the small
                           business issuer's fourth fiscal quarter in the case
                           of an annual report) that has materially affected, or
                           is reasonably likely to materially affect, the small
                           business issuer's internal control over financial
                           reporting; and

         5.       The small business issuer's other certifying officer and I
                  have disclosed, based on our most recent evaluation of
                  internal control over financial reporting, to the small
                  business issuer's auditors and the audit committee of the
                  small business issuer'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 small business issuer'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 small business issuer's internal control
                           over financial reporting.

Date: November 5, 2003                 By: /s/ A. Bronson Thayer
                                           -------------------------------------
                                           A. Bronson Thayer, Chairman and Chief
                                             Executive Officer