31.2

Certification of the Chief Financial Officer under Rule 13a-14(a)
EXHIBIT 31.2


I, Michael D. Mulholland, certify that:

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

2. Based on my knowledge, this quarterly 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 quarterly report;

3. Based on my knowledge, the consolidated financial statements, and other
financial information included in this quarterly 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
quarterly 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 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, including its consolidated subsidiaries, is made known to
us by others within those entities, particularly during the period in
which this quarterly report is being prepared;

(b) Evaluated the effectiveness of the Registrant's disclosure
controls and procedures and presented in this quarterly 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; and

(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 that has materially affected,
or is reasonably likely to materially affect, the Registrant's
internal control over financial reporting; and

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:

(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: August 15, 2005 /s/ Michael D. Mulholland
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Michael D. Mulholland
Chief Financial Officer