Exhibit 32.2

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 Kelly Services, Inc. (the “Company”) on Form 10-Q for the period ended March 30, 2008 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Michael E. Debs, Interim Chief Financial Officer of the Company, 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 Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: May 7, 2008

/s/ Michael E. Debs

Michael E. Debs

Senior Vice President and

Interim Chief Financial Officer

A signed original of this written statement required by Section 906 has been provided to Kelly Services, Inc. and will be retained by Kelly Services, Inc. and furnished to the Securities and Exchange Commission or its staff upon request.