POWER OF ATTORNEY


Know all by these presents, that the undersigned hereby constitutes and
appoints each of Thomas P. Palmer and Christopher R. Harding, Jr.,
signing singly, the undersigned's true and lawful
attorneys-in-fact to:


1. Execute for and on behalf of the undersigned, in the undersigned's
capacity as personal representative of the Estate of William W. Sherertz,
a ten percent shareholder of Barrett Business Services, Inc., a Marlyand
Corporation (the "Company"), Forms 3, 4, and 5 in accordance with
Section 16(a) of the Securities Exchange Act of 1934, as amended,
and the rules thereunder.

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 and timely file such form with the United States
Securities and Exchange Commission; and

3. Take any other action of any type whatsoever in connection with the
foregoing which, in the opinion of such attorney-in-fact, may be of
benefit to, in the best interest of, or legally required by, the
undersigned, it being understood that the documents executed by such
attorney-in-fact on behalf of the undersigned pursuant to this Power
of Attorney shall be in such form and shall contain such terms and
conditions as such attorney-in-fact may approve in such
attorney-in-fact's discretion.

The undersigned hereby grants to each such attorney-in-fact full power
and authority to do and perform any and every act and thing whatsoever
requisite, 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 might or could do if personally present,
with full power of substitution or revocation, hereby ratifying and
confirming all that such attorney-in-fact, or such attorney-in-fact's
substitute or substitutes, 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 any of the undersigned's responsibilities to comply with
Section 16 of the Securities Exchange Act of 1934.

The undersigned agrees that each such attorney-in-fact herein may rely
entirely on information furnished orally or in writing by the
undersigned to such attorney-in-fact.  The undersigned also agrees to
indemnify and hold harmless each such attorney-in-fact against any losses,
claims, damages or liabilities (or actions in these respects) that arise
out of or are based upon any untrue statement or omission of necessary
facts in the information provided by the undersigned to either such
attorney-in-fact for purposes of executing, acknowledging, delivering or
filing Forms 3, 4 or 5 (including amendments thereto) and agrees to
reimburse each such attorney-in-fact for any legal or other expenses
reasonably incurred in connection with investigating or defending
against any such loss, claim, damage, liability or action.


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 10th day of January, 2012.


ESTATE OF WILLIAM W. SHERERTZ


/s/ Kimberly J. Sherertz

___________________________________________
Kimberly J. Sherertz, personal representative