CERTIFICATIONS
                                                                    EXHIBIT 31.1
I, William W. Sherertz, certify that:

  1.  I have  reviewed  this  Annual  Report  on Form 10-K of  Barrett  Business
      Services, Inc.;

  2.  Based on my  knowledge,  this  annual  report  does not contain any untrue
      statement of a material fact or omit to state a material fact necessary to
      make the statements made, in light of the  circumstances  under which such
      statements were made, not misleading with respect to the period covered by
      this annual report;

  3.  Based on my  knowledge,  the  financial  statements,  and other  financial
      information included in this annual report, fairly present in all material
      respects the financial condition,  results of operations and cash flows of
      the  Registrant  as of, and for,  the  periods  presented  in this  annual
      report;

  4.  The  Registrant's  other  certifying  officer  and I are  responsible  for
      establishing  and  maintaining  disclosure  controls  and  procedures  (as
      defined in Exchange Act Rules  13a-15(e) and 15d-15(e) for the  Registrant
      and we have:

      a.   designed such disclosure controls and procedures, or caused such
           disclosure controls and procedures to be designed under our
           supervision, to ensure that material information relating to the
           Registrant is made known to us by others within the company,
           particularly during the period in which this annual report is being
           prepared;

      b.   evaluated the effectiveness of the Registrant's disclosure controls
           and procedures and presented in this annual report our conclusions
           about the effectiveness of the disclosure controls and procedures, as
           of the end of the period covered by this report, based on such
           evaluation;

      c.   disclosed in this report any change in the Registrant's internal
           control over financial reporting that occurred during the
           registrant's most-recent fiscal quarter (the registrant's fourth
           fiscal quarter in the case of an annual report) that has materially
           affected, or is reasonably likely to materially affect, the
           Registrant's internal control over financial reporting;

  5.  The Registrant's other certifying  officer and I have disclosed,  based on
      our most recent  evaluation of internal control over financial  reporting,
      to the  Registrant's  auditors and the audit committee of the Registrant's
      board of directors (or persons performing the equivalent functions):

      a.   all significant deficiencies and material weaknesses in the design or
           operation of internal control over financial reporting which are
           reasonably likely to adversely affect the Registrant's ability to
           record, process, summarize and report financial information; and

      b.   any fraud, whether or not material, that involves management or other
           employees who have a significant role in the Registrant's internal
           control over financial reporting.

Date:  March 30, 2005                     /s/ William W. Sherertz
                                          ---------------------------------
                                          William W. Sherertz
                                          Chief Executive Officer