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                                                                    EXHIBIT 10.1

                      CHANGE OF CONTROL/SEVERANCE AGREEMENT

         This CHANGE OF CONTROL/SEVERANCE AGREEMENT, dated as of December 23,
2003 by and between PAREXEL International Corporation (together with all
subsidiaries or affiliates hereinafter referred to as the "Company") and Susan
H. Alexander (the "Executive").

         WHEREAS, the Executive has been hired as a senior executive of the
Company and is expected to make major contributions to the Company;

         WHEREAS, the Company desires continuity of management; and

         WHEREAS, the Executive is willing to render services to the Company
subject to the conditions set forth in this Agreement.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the Company and the Executive agree
as follows:

         1.       TERMINATION WITHOUT CAUSE. In the event the Company terminates
the Executive's employment with the Company without "Cause" (as such term is
defined in Section 4(c) below), the Company shall pay to the Executive, within
ten business days following the date of termination, a lump sum amount (net of
any required withholding) equal to: (i) twelve (12) months of monthly base
salary (at the highest monthly base salary rate in effect for the Executive in
the twelve month period prior to the termination of his employment), plus (ii)
the pro rata share of the target bonus that could have been payable to the
Executive pursuant to the Company's Performance Bonus Plan (assuming continued
employment) during the year in which the termination occurs, based on bonus
arrangements in effect at any time during the twelve month period immediately
prior to the termination of his employment, such pro rata share to be calculated
from the beginning of the fiscal year in which the termination occurs through
the date of termination.

         2.       TERMINATION PRIOR TO A CHANGE OF CONTROL.

         (a)      Notwithstanding the provisions of Section 1 above, if, within
nine months prior to a Change of Control (as such term is defined in Section
4(b) below) and subsequent to the commencement of substantive discussions that
ultimately result in the Change of Control, the Company terminates the
Executive's employment with the Company without Cause, the Company shall:

                  (1)      Pay to the Executive, within ten (10) business days
                           following the Change of Control, a lump sum amount
                           (net of any required withholding) equal to: (i)
                           twelve (12) months of monthly base salary (at the
                           highest monthly base salary rate in effect for the
                           Executive in the twelve month period prior to

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                           the termination of his employment), plus (ii) the
                           target bonus that could have been payable to the
                           Executive (assuming continued employment) during the
                           year in which the Change of Control occurs based on
                           bonus arrangements in effect at any time during the
                           twelve month period immediately prior to the
                           termination of his employment; and

                  (2)      Provide the Executive and his dependents with life,
                           accident, health and dental insurance substantially
                           similar to that which the Executive was receiving
                           immediately prior to the termination of his
                           employment until the earlier of: (i) the date which
                           is twelve (12) months following the Change of
                           Control; or (ii) the date the Executive commences
                           subsequent employment; and

                  (3)      On the Change of Control, cause any unexercisable
                           installments of any stock options of the Company or
                           any subsidiary or affiliate of the Company held by
                           the Executive on the Executive's last date of
                           employment with the Company that have not expired to
                           become exercisable on the Change of Control;
                           provided, however, that: (i) such acceleration of
                           exercisability shall not occur as to any option if
                           the Change of Control does not occur within the
                           period within which the Executive may exercise such
                           option after a termination of employment in
                           accordance with the provisions of the relevant option
                           agreement and option plan; and (ii) any such
                           acceleration of exercisability shall not extend the
                           period after a termination of employment within which
                           any option may be exercised by the Executive in
                           accordance with the provisions of the relevant option
                           agreement and option plan; and

                  (4)      On the Change of Control, cause any unvested portion
                           of any qualified or non-qualified capital
                           accumulation benefits to become immediately vested
                           (subject to applicable law);

provided, however, that any amounts and benefits set forth in this Section 2
shall be reduced by any and all other severance or other amounts or benefits
paid or payable to the Executive as a result of the termination of his or her
employment.

         3.       TERMINATION FOLLOWING A CHANGE OF CONTROL.

         (a)      Notwithstanding the provisions of Section 1 above, if, at any
time during a period commencing with a Change of Control and ending eighteen
months after such Change of Control, the Company terminates the Executive's
employment without Cause or the Executive terminates his employment with the
Company for "Good Reason" (provided, however, that any such termination by the
Executive must occur promptly (and in any event within 90 days) after the
occurrence of the event or events constituting "Good Reason"), the Company
shall:

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                  (1)      Pay to the Executive, within ten (10) business days
                           following the Executive's last date of employment, a
                           lump sum amount (net of any required withholding)
                           equal to: (i) twelve (12) months of monthly base
                           salary (at the highest monthly base salary rate in
                           effect for such Executive in the twelve (12) month
                           period prior to the termination of his or her
                           employment), plus (ii) the target bonus that could
                           have been payable to such Executive (assuming
                           continued employment) during the year in which the
                           termination of employment occurs based on bonus
                           arrangements in effect immediately prior to the
                           termination of his or her employment (all payments
                           under Sections 1, 2 and this Section 3(a) being
                           referred to collectively, as the "Severance
                           Payments"); and

                  (2)      Provide the Executive and his or her dependents with
                           life, accident, health and dental insurance
                           substantially similar to that which the Executive was
                           receiving immediately prior to the termination of his
                           or her employment until the earlier of: (i) the date
                           which is twelve (12) months following the termination
                           of the Executive's employment; or (ii) the date the
                           Executive commences subsequent employment; and

                  (3)      Cause any unexercisable installments of any stock
                           options of the Company or any subsidiary or affiliate
                           of the Company held by the Executive on the
                           Executive's last date of employment with the Company
                           that have not expired to become exercisable on such
                           last date of employment; provided, however, that: (i)
                           such acceleration of exercisability shall not occur
                           as to any option if the Change of Control does not
                           occur within the period within which the Executive
                           may exercise such option after a termination of
                           employment in accordance with the provisions of the
                           relevant option agreement and option plan; and (ii)
                           any such acceleration of exercisability shall not
                           extend the period after a termination of employment
                           within which any option may be exercised by the
                           Executive in accordance with the provisions of the
                           relevant option agreement and option plan; and

                  (4)      Cause any unvested portion of any qualified and
                           non-qualified capital accumulation benefits to become
                           immediately vested, subject to applicable law;

provided, however, that any amounts and benefits set forth in this Section 3
shall be reduced by any and all other severance or other amounts or benefits
paid or payable to the Executive as a result of the termination of his or her
employment.

         (b)      For purposes of Section 3 above, "Good Reason" shall mean the
occurrence of one or more of the following events following a Change of Control,
as the case may be: (i) the assignment to the Executive of any duties
inconsistent in any adverse, material respect with his position, authority,
duties or responsibilities immediately prior to the Change of Control or any
other action by the Company which results in a material diminution in such
position, authority,

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duties or responsibilities; (ii) a material reduction in the aggregate of the
Executive's base or incentive compensation or the termination of the Executive's
rights to any employee benefits immediately prior to the Change of Control,
except to the extent any such benefit is replaced with a comparable benefit, or
a reduction in scope or value thereof; or (iii) a relocation of the Executive's
place of business which results in the one-way commuting distance for the
Executive increasing by more than 25 miles from the location thereof immediately
prior to the Change of Control (provided, however, that travel consistent with
past practices for business purposes shall not be considered "commuting" for
purposes of this clause (iii)) or (iv) a failure by the Company to obtain the
agreement referenced in Section 4(f).

         4.       GENERAL.

         (a)      In the event the Executive's employment with the Company is
terminated by the Company for "Cause", or the Executive terminates his
employment with the Company other than during the specific time periods set
forth in Section 3 or for any reason other than Good Reason, the Executive shall
not be entitled to the severance benefits or other considerations described
herein by virtue of this Agreement.

         (b)      For purposes of this Agreement, "Change of Control" shall mean
the closing of: (i) a merger, consolidation, liquidation or reorganization of
the Company into or with another Company or other legal person, after which
merger, consolidation, liquidation or reorganization the capital stock of the
Company outstanding prior to consummation of the transaction is not converted
into or exchanged for or does not represent more than 50% of the aggregate
voting power of the surviving or resulting entity; (ii) the direct or indirect
acquisition by any person (as the term "person" is used in Section 13(d)(3) or
14(d)(2) of the Securities Exchange Act of 1934, as amended) of more than 50% of
the voting capital stock of the Company, in a single or series of related
transactions; or (iii) the sale, exchange, or transfer of all or substantially
all of the Company's assets (other than a sale, exchange or transfer to one or
more entities where the stockholders of the Company immediately before such
sale, exchange or transfer retain, directly or indirectly, at least a majority
of the beneficial interest in the voting stock of the entities to which the
assets were transferred).

         (c)      For purposes of this Agreement, "Cause" shall mean: (i) the
commission by the Executive of a felony, either in connection with the
performance of his obligations to the Company or which adversely affects the
Executive's ability to perform such obligations; (ii) gross negligence, breach
of fiduciary duty or breach of any confidentiality, non-competition or
developments agreement in favor of the Company; or (iii) the commission by the
Executive of an act of fraud or embezzlement or other acts in intentional
disregard of the Company which result in loss, damage or injury to the Company,
whether directly or indirectly.

         (d)      Notwithstanding anything to the contrary in this Agreement, if
any portion of any payments received by the Executive from the Company (whether
payable pursuant to the terms of this Agreement or any other plan, agreement or
arrangement with the Company, its successors or any person whose actions result
in a change of control of the Company) shall be subject to tax imposed by
Section 4999 of the Internal Revenue Code of 1986, as amended or any successor
statutory provision, the Company shall pay to the Executive such additional
amounts as are

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necessary so that, after taking into account any tax imposed by Section 4999 (or
any successor statutory provision), and any federal and state income taxes
payable on any such tax, the Executive is in the same after-tax position that he
or she would have been if such Section 4999 (or any successor statutory
provision) did not apply and no payments were made pursuant to this Section
4(d). The Executive and the Company shall each reasonably cooperate with the
other in connection with any administrative or judicial proceedings concerning
the existence or amount of liability for Excise Tax with respect to the
Payments. All determinations required to be made under this Section 4(d),
including whether a Gross-Up Payment is required and the amount of such Gross-Up
Payment, shall be made by the Company, after consultation with its tax and
accounting advisors.

         (e)      The parties hereto expressly agree that the payments by the
Company to the Executive in accordance with the terms of this Agreement will be
liquidated damages, and that the Executive shall not be required to mitigate the
amount of any payment provided for in this Agreement by seeking other employment
or otherwise, nor shall any profits, income, earnings or other benefits from any
source whatsoever create any mitigation, offset, reduction or any other
obligation on the part of the Executive.

         (f)      Except as otherwise provided herein, this Agreement shall be
binding upon and inure to the benefit of the Company and any successor (whether
direct or indirect, by purchase, merger, consolidation, reorganization or
otherwise) of the Company; provided, however, that as a condition of closing any
transaction which results in a Change of Control, the Company shall obtain the
written agreement of any successor (whether direct or indirect, by purchase,
merger, consolidation, reorganization or otherwise) of the Company to be bound
by the provisions of this Agreement as if such successor were the Company and
for purposes of this Agreement, any such successor of the Company shall be
deemed to be the "Company" for all purposes.

         (g)      Nothing in this Agreement shall create any obligation on the
part of the Company or any other person to continue the employment of the
Executive. If the Executive elects to receive the severance and benefits set
forth in Sections 1, 2 or 3, the Executive shall not be entitled to any other
salary continuation or severance benefits in the event of his cessation of
employment with the Company.

         (h)      Nothing herein shall affect the Executive's obligations under
any key employee, non-competition, confidentiality, option or similar agreement
between the Company and the Executive currently in effect or which may be
entered into in the future.

         (i)      This Agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Massachusetts. This Agreement
constitutes the entire Agreement between the Executive and the Company
concerning the subject matter hereof and supersedes any prior negotiations,
understandings or agreements concerning the subject matter hereof, whether oral
or written, and may be amended or rescinded only upon the written consent of the
Company and the Executive. The invalidity or unenforceability of any provision
of this Agreement shall not affect the other provisions of this Agreement and
this Agreement shall be construed and reformed to the fullest extent possible.
The Executive may not assign any of his rights or obligations under this
Agreement; the rights and obligations of the Company under this

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Agreement shall inure to the benefit of, and shall be binding upon, the
successors and assigns of the Company. This Agreement may be executed in any
number of counterparts, all of which taken together shall constitute one and the
same instrument.

         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date first written above.

                                              The Company:

                                              PAREXEL INTERNATIONAL CORPORATION

                                              By:/s/ Josef H. von Rickenbach

                                              Name:Josef H. von Rickenbach

                                              Title:CEO

                                              The Executive:

                                              Signature:/s/ Susan H. Alexander

                                              Printed Name: Susan H. Alexander

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                                                                       EXHIBIT A

                                AGREEMENT/WAIVER

         It is hereby agreed by and between __________________ (the "Executive")
and PAREXEL International Corporation (together with all subsidiaries and
affiliates hereinafter referred to as the "Company"), for good and sufficient
consideration more fully described below, that:

         1.       Consideration. The Company will provide the Executive with the
amounts and benefits described in Sections 1, 2 and 3 of the Change of
Control/Severance Agreement entered into by the Company and the Executive, dated
_________________, (the "Agreement"), subject to the terms and conditions of
such Agreement. The Executive understands that payment of and all such amounts
and benefits are conditioned upon the Executive signing this agreement.

         2.       Settlement of Amounts Due the Executive. The Executive agrees
that the amounts set forth above in Section 1, together with any amounts
previously provided to the Executive by the Company, shall be complete and
unconditional payment, settlement, satisfaction and accord with respect to all
obligations and liabilities of the Company and any of its affiliated companies
(including their respective successors, assigns, shareholders, officers,
directors, employees and/or agents) to the Executive, and all claims, causes of
action and damages by the Executive against the Company and/or any such other
parties regarding the Executive's employment with and termination from
employment with the Company, including, without limitation, all claims for back
wages, salary, draws, commissions, bonuses, vacation pay, equity compensation,
expenses, compensation, severance pay, attorney's fees, compensatory damages,
exemplary damages, or other costs or sums.

         3.       Release.

         (a)      In exchange for the amounts and benefits described in Section
1 above and other good and valuable consideration, receipt of which is hereby
acknowledged, the Executive and his representatives, agents, estate, successors
and assigns, absolutely and unconditionally hereby release and forever discharge
the Company, its affiliated companies and/or their successors, assigns,
directors, shareholders, officers, employees and/or agents, both individually
and in their official capacities, (the "Releasees"), from any and all actions or
causes of action, suits, claims, complaints, contracts, liabilities, agreements,
promises, debts and damages, controversies, judgments, rights and demands,
whether existing or contingent, known or unknown, which arise under the
Agreement. This release is intended by the Executive to be all encompassing and
to act as a full and total release of any claims that the Executive may have or
has had against the Releasees under the Agreement, including, but not limited
to, any federal, state or local law or regulation dealing with either employment
or employment discrimination such as those laws or regulations concerning
discrimination on the basis of age, race, color, religion, creed, sex, sexual-
orientation, national origin, ancestry, marital status, physical or mental
disability, any veteran status or any military service or application for any
military service; any contract, whether oral or written, express or implied; or
common law.

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         (b)      The Executive agrees not only to release and discharge the
Releasees from any and all claims as stated above that the Executive could make
on his/her own behalf or on behalf of others, but also those claims which might
be made by any other person or organization on behalf of the Executive, and the
Executive specifically waives any right to become, and promises not to become, a
member of any class in a case in which a claim or claims against the Releasees
are made involving any matters which arise out of, or in connection with, the
Agreement. Nothing in this agreement is to be construed as an admission by the
Releasees of any liability or unlawful conduct whatsoever.

         4.       Waiver of Rights and Claims Under the Age Discrimination and
Employment Act of 1967.

         (a)      The Executive has been informed that since he is 40 years of
age or older, he has or might have specific rights and/or claims under the Age
Discrimination and Employment Act of 1967. In consideration for the amounts
described in Section 1 hereof, the Executive specifically waives such rights
and/or claims to the extent that such rights and/or claims arose prior to the
date this Agreement was executed.

         (b)      The Executive was advised by the Company of his right to
consult with an attorney prior to executing this Agreement.

         (c)      The Executive was further advised when he was presented by the
Company with the original draft of this Agreement on _______, 200_, that he had
at least 21 days within which to consider its terms and to consult with or seek
advice from an attorney or any other person of his/her choosing, until the close
of business on __________, 200_.

         5.       Confidentiality. The Executive agrees he shall not divulge or
publish, directly or indirectly, any information whatsoever regarding the
substance, terms or existence of the Agreement or this agreement and/or any
discussions or negotiations relating to the Agreement or this agreement to any
person or organization, except to his immediate family members, counsel or
accountant, and unless required under law or court order.

         6.       Representations and Governing Law.

         (a)      This agreement represents the complete and sole understanding
between the parties regarding the subject matter hereto. This agreement may not
be modified, altered or rescinded except upon written consent of the Company and
Executive. The invalidity or unenforceability of any provision of this agreement
shall not affect the other provisions of this agreement, but this agreement
shall be revised, construed and reformed to the fullest extent possible to
effectuate the purposes of this agreement. This agreement shall be binding upon
and inure to the benefit of the Company and the Executive and their respective
heirs, successors and assigns. The parties agree that the Company will not have
an adequate remedy if the Executive fails to comply with Sections 3, 4, and 5
hereof and that damages will not be readily ascertainable, and that in the event
of such failure, the Executive shall not oppose any application by the Company
requiring a

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decree of specific performance or an injunction enjoining a breach of this
agreement. If the Executive breaches any of his/her obligations hereunder, he
shall forfeit all right to payments pursuant to Section 1.

         (b)      This agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Massachusetts, without giving
effect to the principles of conflicts of law thereof.

         (c)      The Executive represents that he has read this agreement,
fully understands the terms and conditions of such agreement, and is voluntarily
executing the same. In entering into this agreement, the Executive does not rely
on any representation, promise or inducement made by the Releasees, with the
exception of the consideration described in this document.

         7.       Effective Date. The Executive may revoke this agreement during
the period of seven (7) days following its execution by the Executive, and this
agreement shall not become effective or enforceable until this revocation period
has expired.

                                         The Company:

                                         PAREXEL INTERNATIONAL CORPORATION

                                         By:_____________________________

                                         Name:___________________________

                                         Title:__________________________

                                         Date:___________________________

                                         The Executive:

                                         Signature:______________________

                                         Printed Name:___________________

                                         Date:___________________________

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