CERTIFICATION
                                                                    Exhibit 31.1
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        I, William D. Sullivan, certify that:

        1. I have reviewed this quarterly report for the fiscal quarter ended
June 30, 2006 on Form 10-Q of Pioneer Financial Services, Inc.;

        2. Based on my knowledge, this 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 report;

        3. Based on my knowledge, the financial statements, and other financial
information included in this 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 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 report is being prepared;

               (b) Evaluated the effectiveness of the registrant's disclosure
        controls and procedures and presented in this report our conclusions
        about the effectiveness of the 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 (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

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               (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 14, 2006

                                 /s/ William D. Sullivan
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                                 William D. Sullivan
                                 Chief Executive Officer