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                                                                    Exhibit 10.4

                            PRIDE INTERNATIONAL, INC.
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                             PARTICIPATION AGREEMENT

            THIS PARTICIPATION AGREEMENT (this "Participation Agreement"),
entered into effective as of August 12, 2004 (the "Effective Date"), by and
between Pride International, Inc. (the "Company"), and John C.G. O'Leary (the
"Executive");

                                   WITNESSETH:

            WHEREAS, the Company has established the Pride International, Inc.
Supplemental Executive Retirement Plan, as amended and restated effective May
18, 2004 (the "Plan"), to generally assist the Company and its Affiliates in
retaining, attracting and providing a retirement benefit to certain selected
salaried officers and other key management employees; and

            WHEREAS, the Company and the Executive have entered into an
employment agreement, effective as of February 5, 1999 (the "Employment
Agreement"); and

            WHEREAS, the Company has previously designated the Executive to
participate in the Prior Plan; and

            WHEREAS, the Company and the Executive desire to enter into a
Participation Agreement under the Plan to supersede any prior agreements or
understandings in their entirety; and

            NOW, THEREFORE, in consideration of the premises and other good and
valuable consideration, the Company and the Executive agree to the form of this
Participation Agreement as follows:

            1. Reference to Plan. Terms not otherwise defined herein shall have
the same meaning as ascribed thereto in the Plan. This Participation Agreement
is being entered into in accordance with and subject to all of the terms,
conditions and provisions of the Plan and administrative interpretations
thereunder, if any, which have been adopted by the Committee and are still in
effect on the date hereof. The Executive acknowledges he has received a copy of,
and is familiar with the terms of, the Plan which are hereby incorporated herein
by reference.

            2. Benefit Percentage. As of the Effective Date and subject to the
forfeiture and vesting requirements of the Plan as supplemented by this
Participation Agreement, the Executive is a Participant in the Plan and is
entitled to a SERP Benefit equal to 40% of Final Annual Salary, as described in
Section 4 of the Plan, subject to the applicable reduction factor as set forth
in Section 4.8 of the Plan for payments provided before Executive's Normal
Retirement Date.

            3. Vesting. The Executive's contingent right to receive the SERP
Benefit shall vest on the dates and in the percentages as set forth below:

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<TABLE>
<CAPTION>
     Date                          Percentage Vested
     ----                          -----------------
<S>                                <C>
January 2, 2004                            20%
January 2, 2005                            40%
January 2, 2006                            60%
January 2, 2007                            80%
January 2, 2008                            100%
</TABLE>

Except for the amount of the benefit payable being reduced to the applicable
Percentage Vested set forth above, any benefit payable under this paragraph 3
shall be payable on all of the same terms and conditions, including timing, set
forth in the Plan for a Early or Normal Retirement Benefit, as applicable.

            4. Early Retirement. As of the Effective Date, the Executive shall
be deemed to have fifteen years of Service for purposes of determining
eligibility for an Early Retirement Benefit as provided in Section 4.2 of the
Plan.

            5. Change in Control. To the extent the Executive is entitled to a
supplemental payment (a "gross-up payment") to be made pursuant to the
Employment Agreement to the Executive as necessary to offset or mitigate the
impact of the golden parachute excise tax on the Executive, such provision shall
control with respect to any benefit paid to the Executive pursuant to Section
4.4 of the Plan.

            6. Tax Withholding. The Executive agrees that the payor of the Plan
benefit may take whatever steps the payor, in its sole discretion, deems
appropriate or necessary to satisfy state and federal income tax, social
security, Medicare, other tax withholding obligations arising out of the
benefits payable under this Participation Agreement.

            7. Status of Participation Agreement. The benefits payable under
this Participation Agreement shall be independent of, and in addition to, any
other agreement relating to the Executive's employment that may exist from time
to time between the parties hereto, or any other compensation payable by the
Employer to the Executive, whether salary, bonus or otherwise. This
Participation Agreement shall not be deemed to constitute a contract of
employment between the parties hereto, nor shall any provision hereof, except as
expressly stated, restrict the right of the Employer to discharge the Executive
or restrict the right of the Executive to terminate the Executive's employment.

            8. Entire Agreement. This Participation Agreement and the Plan
constitute the entire understanding between the parties hereto with respect to
the subject matter hereof, and all promises, representations, understandings,
arrangements and prior agreements, including any agreements under the Prior
Plan, are superseded in their entirety by this Participation Agreement and the
Plan. The terms and conditions of this Participation Agreement and the Plan
supersede Sections 3.05(d) and (f) of the Employment Agreement or any such other
successor provisions and Sections 3.05(d) and (f) of the Employment Agreement
are not applicable to any benefit under the Plan. This Participation Agreement
may be amended, modified or terminated, in whole or in part, at any time by a
written instrument executed by both parties hereto. Notwithstanding

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anything to the contrary in the Plan, this Participation Agreement may set forth
specific terms or provisions modifying the terms of the Plan with respect to the
Executive, and the terms of this Participation Agreement shall be controlling.

            9. Severability. If, for any reason, any provision of this
Participation Agreement is held invalid, in whole or in part, such invalidity
shall not affect any other provision of this Agreement not so held invalid, and
each such other provision shall to the full extent consistent with law continue
in full force and effect. If this Agreement or any portion thereof conflicts
with any law or regulation governing the activities of the Employer, this
Participation Agreement or appropriate portion thereof shall be deemed invalid
and of no force or effect.

            10. Governing Law. This Participation Agreement shall be governed by
and construed in accordance with the laws of the State of Texas.

            IN WITNESS WHEREOF, the parties have executed this Participation
Agreement (in multiple copies) on August 12, 2004, but effective as of the day
and year first above written.

                                          PRIDE INTERNATIONAL, INC.

                                          By /s/ Paul A. Bragg
                                             -----------------------------------
                                             Paul A. Bragg
ATTEST:                                      Chief Executive Officer

/s/ W. Gregory Looser
-------------------------
W. Gregory Looser
Secretary

                                             /s/ John C.G. O'Leary
                                             -----------------------------------
                                             EXECUTIVE

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