Exhibit 31.1

# Certification of Chief
Executive Officer

I,
Erik Vonk, certify that:

|(1) | I
have reviewed this quarterly report on Form 10-Q for the quarter ended September
          30, 2004 of Gevity HR, Inc.;
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|(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;
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|(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
registrant as of, and                     for, the periods presented in this report;
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|(4) | The
registrants other certifying officer(s) 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:
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| | 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 report is being prepared;
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| | 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
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| | 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 (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
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|(5) | The
registrants other certifying officer(s) 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
equivalent functions):
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| | 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
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| | 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.
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|                        |  |                                  
|----------------------- |  | ---------------------------------
|Dated: November 9, 2004 |  | /s/ ERIK VONK                    
|                        |  | Erik Vonk
Chief Executive Officer
|                        |  |