Form: 10-Q

Quarterly report pursuant to Section 13 or 15(d)

August 14, 2006

EXHIBIT 32

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350

In connection with the Quarterly Report of Barrett Business Services, Inc. (the “Company”) on Form 10-Q for the period ended June 30, 2006, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned certify, pursuant to 18 U.S.C. § 1350, 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.

/s/ William W. Sherertz /s/ Michael D. Mulholland
William W. Sherertz
Chief Executive Officer
August 11, 2006
Michael D. Mulholland
Chief Financial Officer
August 11, 2006