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                                                                   Exhibit 10.11


                          SECURITIES PURCHASE AGREEMENT

         This Securities Purchase Agreement (this "Agreement"), dated as of June
26, 2001, is by and among GENSTAR CAPITAL PARTNERS III, L.P., a Delaware limited
partnership ("Genstar"), STARGEN III, L.P., a Delaware limited partnership
("Stargen," and, together with Genstar, the "Purchasers," and each, a
"Purchaser") and PRA HOLDINGS, INC., a Delaware corporation (the "Company").

                                    RECITALS

         On or about the date hereof, Virginia Merger Sub, Inc., a Delaware
corporation and an indirect wholly owned subsidiary of the Company ("Merger
Sub") is merging with and into PRA International, Inc., a Delaware corporation
("PRA, Inc.") pursuant to an Agreement and Plan of Merger dated as of May 16,
2001 (the "Merger Agreement") by and among the Company, PRA Sub, Inc., a
Delaware corporation and a wholly owned subsidiary of the Company, Merger Sub,
PRA, Inc. and the other persons listed on the signatures pages thereto.

         Subject to the terms and conditions of this Agreement, each Purchaser
is willing to purchase, and the Company is willing to issue and sell to such
Purchaser, the number of shares of Common Stock (defined hereunder) set forth
opposite the name of such Purchaser on Schedule 1 hereto.

         It is anticipated that on or about the date hereof, pursuant to the
Merger Agreement, among other things (i) the Merger (as defined in the Merger
Agreement) will be consummated, (ii) the Company and certain other purchasers
(the "Other Purchasers") will enter into one or more Subscription Agreements,
(iii) the Company, the Purchasers and the Other Purchasers will enter into a
Stockholders Agreement substantially in the form attached hereto as Exhibit A,
and (iv) the Company and the Purchasers will enter into the Registration Rights
Agreement substantially in the form attached hereto as Exhibit B.

                                    AGREEMENT

         In consideration of the foregoing, and the representations, warranties,
covenants and conditions set forth below, the parties hereto hereby agree as
follows:

         1.       Purchase of Securities, etc.

                  (a)      Purchase of Securities. Subject to all of the terms
 and conditions of this Agreement, each Purchaser hereby agrees to purchase from
the Company, and the Company hereby agrees to sell to each Purchaser, the number
of shares of its common stock, par value $.01 per share (the "Common Stock"),
set forth opposite the name of such Purchaser on Schedule 1 hereto at the
respective purchase prices set forth on Schedule 1. The Common Stock is referred
to in this Agreement as the "Securities," and the aggregate of the purchase
price for the Securities is referred to as the "Purchase Price."

                  (b)      Delivery of Funds and Certificates. The closing of
the purchase and sale of the Securities (the "Closing") shall take place at a
time and place to be designated by the
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Company on at least 24 hours' notice. At the Closing, the Company will deliver
to each Purchaser a duly executed stock certificate, registered in each
Purchaser's name and representing the Common Stock, against payment of the
Purchase Price therefor by delivery to the Company by wire transfer of
immediately available funds in the amount of the Purchase Price representing
payment in full for the Securities.

                  (c)      Legend. The certificate (or certificates)
representing the Common Stock shall bear a legend in substantially the following
form:


                  "THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO
                  A STOCKHOLDERS AGREEMENT DATED AS OF JUNE 27, 2001 AMONG PRA
                  HOLDINGS, INC. (THE "COMPANY") AND CERTAIN OF THE COMPANY'S
                  STOCKHOLDERS, AS AMENDED AND MODIFIED FROM TIME TO TIME. A
                  COPY OF SUCH STOCKHOLDERS AGREEMENT SHALL BE FURNISHED WITHOUT
                  CHARGE BY THE COMPANY TO THE HOLDER HEREOF UPON WRITTEN
                  REQUEST.

                  THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
                  "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS AND MAY NOT BE
                  TRANSFERRED, SOLD OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO
                  AN EFFECTIVE REGISTRATION UNDER THE SECURITIES ACT OR PURSUANT
                  TO AN OPINION OF COUNSEL, SATISFACTORY TO THE COMPANY, TO THE
                  EFFECT THAT AN EXEMPTION FROM SUCH REGISTRATION IS AVAILABLE."

                  (d)      Management Rights. After the Closing and so long as
each Purchaser owns any shares of the Common Stock of the Company, each
Purchaser shall have the right to elect at least one Director to the Company's
Board of Directors in order to substantially participate in and substantially
influence the conduct of the management of the Company and its business.

         2.       Representations and Warranties of the Purchasers. Each
Purchaser individually (but not on behalf of any other Purchaser) represents and
warrants that:

                  (a)      Such Purchaser has full legal capacity, power and
authority to execute and deliver this Agreement, the Stockholders Agreement and
the Registration Rights Agreement and to perform its obligations hereunder and
thereunder. This Agreement has been, and on or before the Closing the
Stockholders Agreement and the Registration Rights Agreement will be, duly
authorized, executed and delivered by each Purchaser and this Agreement is, and
on and after the Closing the Stockholders Agreement and the Registration Rights
Agreement will be, the legal, valid and binding obligation of such Purchaser,
enforceable against it in accordance with the terms hereof and thereof, subject
to (i) the effect of bankruptcy, insolvency, reorganization,

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moratorium, fraudulent conveyance, fraudulent transfer, preferential transfer or
distribution laws and other similar laws now or hereafter in effect relating to
or affecting the rights of creditors generally; and (ii) the effect of (A)
general principles of equity, including without limitation concepts of
materiality, reasonableness, good faith and fair dealing and the possible
unavailability of specific performance or injunctive relief, regardless of
whether considered in a proceeding in equity or at law and (B) the discretion of
any court in which an action is brought.

                  (b)      Such Purchaser has been advised that the Securities
have not been registered under the Securities Act of 1933, as amended (the
"Securities Act") or any state securities laws and, therefore, cannot be resold
unless they are registered under the Securities Act and applicable state
securities laws or unless an exemption from such registration requirement is
available. Such Purchaser is purchasing the Securities to be acquired by such
Purchaser hereunder for its own account and not with a view to, or for resale in
connection with, the distribution thereof in violation of the Securities Act.
Such Purchaser is aware that the Company is under no obligation to effect any
such registration with respect to the Securities (except solely to the extent,
if any, provided in the Registration Rights Agreement) or to file for or comply
with any exemption from registration. Such Purchaser is purchasing the
Securities to be acquired by such Purchaser hereunder for its own account and
not with a view to, or for resale in connection with, the distribution thereof
in violation of the Securities Act.

                  (c)      Such Purchaser has such knowledge and experience in
financial and business matters that such Purchaser is capable of evaluating the
merits and risks of such investment, is able to incur a complete loss of such
investment and is able to bear the economic risk of such investment for an
indefinite period of time. Such Purchaser has had the opportunity to ask
questions of the Company with respect to the Company, the Securities, the Merger
and related transactions and to receive such information from the Company
regarding such matters as it deems necessary in making its decision to purchase
the Securities. Such Purchaser is an "accredited investor" as that term is
defined in Regulation D under the Securities Act.

         3.       Representations and Warranties of the Company. The Company
represents and warrants to each Purchaser that:

                  (a)      The Company is duly organized, validly existing and
in good standing under the laws of the State of Delaware. The Company has full
corporate power and authority to carry on the businesses in which it is engaged
and to own, lease and use the properties owned, leased and used by it.

                  (b)      The Company has or prior to the Closing will have
taken all corporate action required to authorize the execution and delivery of
this Agreement, the Stockholders Agreement and the Registration Rights Agreement
and the issuance of the Securities.

                  (c)      The Securities, when issued and upon payment of the
purchase price therefor, will be duly authorized, validly issued, fully paid and
non-assessable.

                  (d)      This Agreement has been, and on or before the Closing
the Stockholders Agreement and the Registration Rights Agreement will be, duly
authorized, executed and delivered by the Company and this Agreement is, and on
and after the Closing the Stockholders

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Agreement and the Registration Rights Agreement will be, a legal, valid and
binding obligation of the Company, enforceable against it in accordance with its
respective terms, subject to (a) the effect of bankruptcy, insolvency,
reorganization, moratorium, fraudulent conveyance, fraudulent transfer,
preferential transfer or distribution laws and other similar laws now or
hereafter in effect relating to or affecting the rights of creditors generally;
and (b) the effect of (i) general principles of equity, including without
limitation concepts of materiality, reasonableness, good faith and fair dealing
and the possible unavailability of specific performance or injunctive relief,
regardless of whether considered in a proceeding in equity or at law and (ii)
the discretion of any court in which an action is brought.

         4.       Restrictions on Transfer. All certificates representing
Securities shall bear legends in the form required under the Stockholders
Agreement until such time as they may be removed as provided therein.

         5.       Conditions to Issuance of Securities. The Company's obligation
to issue and sell the Securities to any Purchaser shall be subject to the
satisfaction of the following conditions:

                  (a)      All representations and warranties of such Purchaser
contained in this Agreement shall be true and correct as of the Closing, and
consummation of the purchases contemplated hereby shall constitute a
reaffirmation by each Purchaser that all representations and warranties of such
Purchaser contained in this Agreement are true and correct as of the Closing.

                  (b)      On or before the Closing, substantially
contemporaneously with the issuance and sale of the Securities hereunder, each
Purchaser shall have duly executed and delivered to the Company a counterpart of
the Stockholders Agreement, the Registration Rights Agreement and such other
documents as the Company may reasonably request in connection with the
transactions contemplated hereby (and the execution of this Agreement
constitutes the agreement of the Purchaser to so execute such documents).

         6.       Miscellaneous.

                  (a)      Notices. All notices and other communications
required or permitted to be given under this Agreement shall be in writing and
shall be deemed to have been given if delivered personally or sent by certified
mail, return receipt requested, postage prepaid, to the parties to this
Agreement at the following address or to such other address as a party to this
Agreement shall specify by notice to the other parties hereto:

         if to either Purchaser:

                  c/o Genstar Capital, L.P.
                  555 California Street, Suite 4850
                  San Francisco, CA 94104
                  Attention:  Jean-Pierre L. Conte
                  Telecopy No.:  (415) 834-2383

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         with copies (which shall not constitute notice) to:

                  Latham & Watkins
                  505 Montgomery Street, Suite 1900
                  San Francisco, CA 94111
                  Attention:  Scott Haber
                  Telecopy No.:  (415) 395-8095

         if to the Company:

                  PRA Holdings, Inc.
                  8300 Greensboro Drive, Suite 400
                  McLean, VA 22102
                  Attention:  President
                  Telecopy No.: (703) 748-5199

All such notices and communications shall be deemed to have been received on the
date of delivery or on the third business day after the mailing thereof.

                  (b)      Binding Effect; No Assignment; Benefits. This
Agreement shall be binding upon and inure to the benefit of the parties to this
Agreement and their respective successors and assigns; provided that neither
this Agreement nor any right, remedy, obligation or liability arising hereunder
or by reason hereof shall be assignable by either the Company or any Purchaser
without the prior written consent of the other party. Nothing in this Agreement,
express or implied, is intended or shall be construed to give any person other
than the parties to this Agreement or their respective successors or assigns any
legal or equitable right, remedy or claim under or in respect of any agreement
or any provision contained herein.

                  (c)      Survival. All covenants, agreements, representations
and warranties made herein shall survive the execution and delivery hereof and
transfer of any Securities.


                  (d)      Waiver. Either party hereto may by written notice to
the other (a) extend the time for the performance of any of the obligations or
other actions of the other under this Agreement; (b) waive compliance with any
of the conditions or covenants of the other contained in this Agreement; and (c)
waive or modify performance of any of the obligations of the other under this
Agreement. Except as provided in the preceding sentence, no action taken
pursuant to this Agreement, including, without limitation, any investigation by
or on behalf of any party, shall be deemed to constitute a waiver by the party
taking such action of compliance with any representations, warranties, covenants
or agreements contained herein. The waiver by any party hereto of a breach of
any provision of this Agreement shall not operate or be construed as a waiver of
any preceding or succeeding breach and no failure by either party to exercise
any right or privilege hereunder shall be deemed a waiver of such party's rights
or privileges hereunder or shall be deemed a waiver of such party's rights to
exercise the same at any subsequent time or times hereunder.

                  (e)      Amendment. This Agreement may be amended, modified or
supplemented only by a written instrument executed by each Purchaser and the
Company.

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                  (f)      Expenses. The Company agrees that, whether or not the
transactions contemplated by this Agreement are consummated, the Company will
pay or cause to be paid all costs and expenses arising in connection with the
preparation, execution, administration and enforcement of, and the preservation
of rights under, this Agreement, including without limitation:

                           (1)      all taxes (other than taxes based on
income), fees or other charges which may be payable in connection with the sale
or purchase of the Securities pursuant to this Agreement;

                           (2)      all expenses incurred by each Purchaser in
connection with the maintenance of its books and records, preparation of tax
returns and delivery of tax information to its partners;

                           (3)      all expenses incurred by each Purchaser in
connection with its organization, including, without limitation, legal fees;

                           (4)      all reasonable expenses relating to any
amendment or modification of, or any waiver or consent under, any agreement
pertaining to the Merger to which each Purchaser is a party; and

                           (5)      all reasonable travel and other
out-of-pocket expenses of the general partner of each Purchaser incurred in
connection with the operation and business of such Purchaser and such
Purchaser's ownership of the Securities.

                  (g)      Indemnification. Whether or not the transactions
contemplated hereby are consummated, the Company agrees to indemnify and hold
harmless each Purchaser and all limited and general partners of each Purchaser
from and against any liabilities, obligations, losses, damages, penalties,
actions, judgments, suits, claims, costs, attorneys' fees, expenses and
disbursements of any kind which may be imposed upon, incurred by or asserted
against either Purchaser (or any partner thereof) in any manner relating to or
arising out of (i) each Purchaser's purchase and/or ownership of the Securities,
(ii) the Merger, or (iii) any litigation to which either Purchaser (or any of
its partners) is made a party in its capacity as a stockholder or owner of the
Securities (or a partner of a stockholder or owner of such Securities) of the
Company.

                  (h)      Limited Liability of Partners and Members.
Notwithstanding any other provision of this Agreement, neither the general
partner nor the limited partners nor any future general or limited partner of
each Purchaser, and no member, partner or shareholder of any such general
partner or limited partner, shall have any personal liability for performance of
any obligation of such Purchaser under this Agreement in excess of the
respective capital contribution of such general partner and limited partners to
such Purchaser.

                  (i)      Applicable Law. This Agreement shall be governed by
and construed in accordance with the laws of New York, without giving effect to
any choice or conflict of law provision or rule that would cause the application
of the domestic substantive laws of any other jurisdiction.

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                  (j)      Section and Other Headings. The section and other
headings contained in this Agreement are for reference purposes only and shall
not affect the meaning or interpretation of this Agreement.


                  (k)      Counterparts. This Agreement may be executed in any
number of counterparts, each of which shall be deemed to be an original and all
of which together shall be deemed to be one and the same instrument.


                  [Remainder of Page Intentionally Left Blank]



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         IN WITNESS WHEREOF, the Company and each Purchaser have executed this
Agreement as of the day and year first above written.

                                             PRA HOLDINGS, INC.


                                             By: /s/ JEAN-PIERRE L. CONTE
                                                 -------------------------------
                                                 Name: Jean-Pierre L. Conte
                                                      --------------------------
                                                 Its: President
                                                     ---------------------------



                                             GENSTAR CAPITAL PARTNERS III, L.P.

                                                By:   Genstar Capital III, L.P.
                                                Its:  General Partner

                                                      By:   Genstar III GP LLC
                                                      Its:  General Partner


                                             By: /s/ JEAN-PIERRE L. CONTE
                                                 -------------------------------
                                                 Name: Jean-Pierre L. Conte
                                                      --------------------------
                                                 Its: Managing Director
                                                     ---------------------------


                                             STARGEN III, L.P.

                                                By:   Genstar Capital III, L.P.
                                                Its:  General Partner

                                                      By:   Genstar III GP LLC
                                                      Its:  General Partner


                                             By: /s/ JEAN-PIERRE L. CONTE
                                                 -------------------------------
                                                 Name: Jean-Pierre L. Conte
                                                      --------------------------
                                                 Its: Managing Director
                                                     ---------------------------





                 [Securities Purchase Agreement signature page]