Exhibit 32.1

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO SECTION 906

OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Kforce Inc. (“Kforce”) on Form 10-Q for the quarterly period ended June 30, 2008 as filed with the Securities and Exchange Commission on the date hereof (the “Form 10-Q”), I, David L. Dunkel, Chief Executive Officer of Kforce, hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1) The Form 10-Q fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

2) The information contained in the Form 10-Q fairly presents, in all material respects, the financial condition and results of operations of Kforce.

Date: July 30, 2008

/s/ David L. Dunkel

David L. Dunkel,

Chief Executive Officer

(Principal Executive Officer)