POWER OF ATTORNEY

POWER OF ATTORNEY

Know all by these presents, that the undersigned hereby constitutes and
appoints each of Michael D. Mulholland and James D. Miller, signing singly, the
undersigned's true and lawful attorney-in-fact to:

1. Execute for and on behalf of the undersigned, in the undersigned's
capacity as an officer and/or director of Barrett Business Services, Inc. (the
"Company"), Forms 3, 4, and 5 in accordance with Section 16(a) of the Securities
Exchange Act of 1934 and the rules thereunder, and any other forms or reports
the undersigned may be required to file in connection with the undersigned's
ownership, acquisition, or disposition of securities of the Company; and

2. Do and perform any and all acts for and on behalf of the undersigned
which may be necessary or desirable to complete and execute any such Form 3, 4,
or 5, or other form or report, and timely file such form or report with the
United States Securities and Exchange Commission and any stock exchange or
similar authority as appropriate.

The undersigned hereby grants to each such attorney-in-fact full power and
authority to do and perform any and every act and thing necessary or proper to
be done in the exercise of any of the rights and powers herein granted, as fully
to all intents and purposes as the undersigned could do if personally present,
hereby ratifying and confirming all that such attorney-in-fact shall lawfully do
or cause to be done by virtue of this power of attorney and the rights and
powers herein granted. The undersigned acknowledges that the foregoing
attorneys-in-fact, in serving in such capacity at the request of the
undersigned, are not assuming, and the Company is not assuming, any of the
undersigned's responsibilities to comply with Section 16 of the Securities
Exchange Act of 1934.

This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4, and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.

IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 20th day of August, 2003.


/s/ William W. Sherertz
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Signature

William W. Sherertz
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