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                                                                   Exhibit 10.23

                         EXECUTIVE EMPLOYMENT AGREEMENT


     THIS AGREEMENT made as of the 24 day of July, 1996,


BY AND BETWEEN:                MICHAEL F. ANKCORN

                               (hereinafter referred to as the "Employee")


AND:                           CLINTRIALS BIORESEARCH LTD.

                               (hereinafter referred to as the "Employer")


     WHEREAS the Employee is a key executive of the Employer and has made
valuable contributions to the productivity and profitability of the Employer;

     AND WHEREAS the Employer considers it essential and in the best interests
of the Employer that the Employee be encouraged to remain with the Employer and
to continue to devote his full attention to the Employer's business;

     AND WHEREAS the Employer and the Employee desire to enter into this
Agreement setting forth the terms and conditions of employment of the Employee
with the Employer and the benefits attaching thereto.


     NOW, THEREFORE, the parties hereto agree as follows:


                                   ARTICLE 1.
                                 INTERPRETATION

1.1  DEFINITIONS.  Where used herein or in any amendments hereto or in any
communication required or permitted to be given hereunder, the following terms
shall have the following meanings, respectively, unless the context otherwise
requires:

(a)  "ACTIVITY" shall mean any act, undertaking or decision whatsoever taken,
     effectuated or made in respect of, or relating to, the Business; and
     "Activities" shall mean the aggregate thereof.

(b)  "AGREEMENT" shall mean this Employment Agreement and all instruments
     supplemental hereto or in amendment or confirmations hereof; "herein",
     "hereof", "hereto", "hereunder" and similar expressions mean and refer to
     this Agreement and not to any particular Article, Section, Subsection or
     other subdivision; "Article", "Section", "Subsection" or other subdivision
     of this Agreement means and refers to the specified Article, Section,
     Subsection or other subdivision of this Agreement.


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(c)  "BONUS" shall mean the amounts payable to the Employee pursuant to any
     bonus or incentive compensation plan referred to at Section 8.1.

(d)  "BUSINESS" shall mean, in relation to the Employer, the business now and
     hereafter conducted by the Employer up to the date of termination of this
     Agreement, as well as the business that the Employer is in the process of
     developing at the time of termination of this Agreement. Without limiting
     the generality of the foregoing, the business at the time of signature of
     this Agreement can generally be described as the business of designing and
     conducting research programs for pharmaceuticals, bioengineered products,
     chemical compounds, biomaterials and other similar substances.

(e)  "CAUSE" shall mean any event or circumstance which, pursuant to applicable
     law, constitutes cause for dismissal without either notice or payment in
     lieu of notice.

(f)  "CHANGE OF CONTROL" shall mean:

     the sale by ClinTrials Research, Inc. ("CTR") of shares and/or other
     securities of the Employer of which are attached votes which may be cast to
     elect directors of the Employer ("Voting Shares") such that the remaining
     Voting Shares held by CTR are, in the aggregate, equal to or fewer than
     fifty percent (50%) of all Voting Shares of the Employer, as a result of
     which a Person, or a group of Persons, or Persons acting in concert, or
     Persons associated or affiliated with any such Person or group within the
     meaning of the Canada Business Corporation Act, other than CTR would be in
     a position to exercise effective control over the Employer.

(g)  "CONFIDENTIAL INFORMATION" shall mean all information (including, without
     limiting the generality of the foregoing, all information related to
     processes, formulae, research and development, finance, marketing, and all
     names of, or lists of, customers or sponsors) howsoever received by the
     Employee from, through or relating to the Employer, and in whatever form
     (whatever oral, written, machine readable or otherwise), which pertains to
     the Employer; provided, however, that the term "Confidential Information"
     shall not include information which:

     (i)  is in the public domain without any fault or responsibility on the
          Employee's part;

          or

     (ii) is properly within the legitimate possession of the Employee prior to
          its disclosure and without any obligation of confidentiality attaching
          thereto; or

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     (iii) after disclosure, is lawfully received by the Employee from another
           Person who is lawfully in possession of such Confidential Information
           and such other Person was not restricted from disclosing the said
           information to the Employer; or

     (iv)  is independently developed by the Employee through Persons who have
           not had assets to, or knowledge of, the Confidential Information; or

     (v)   is approved by the Employer for disclosure prior to its actual
           disclosure.

(h) "EMBODIMENTS" shall include, without limitation, all designs, drawings,
    sketches, blueprints, photographs, films, models, charts and maps.

(i) "GOVERNMENTAL BODY" shall mean:

     (i)   any domestic or foreign national, federal, provincial, state,
           municipal or other government body;

     (ii)  any subdivision, ministry, department, secretariat, bureau, agency,
           commission, board, instrumentality or authority of any of the
           foregoing governments or bodies;

     (iii) any quasi-governmental or private body exercising any regulatory,
           expropriation or taxing authority under or for the account of any of
           the foregoing governments or bodies; or

     (iv)  any domestic or foreign judicial, quasi-judicial, arbitration or
           administrative court, grand jury, commission, board or panel.

(j) "INCAPACITY" shall mean any medical condition whatsoever which leads to the
    Employee's absence from the Employee's job function for a continuous period
    of six (6) months, without the Employee being able to resume functions on a
    full time basis at the expiration of such period, and any unsuccessful
    attempts to return to work for periods under fifteen (15) days shall not
    interrupt the calculation of the said six (6) months period; or

    a condition of total and continuing disability which renders the Employee
    incapable of performing his essential job duties and functions.

(k) "INVOLUNTARY TERMINATION" shall mean:

     (i)   any actual or express termination by the Employer of the Employee's
           employment following any Change of Control which is not due to the
           death of the Employee, the Employee's voluntary resignation or
           incapacity;



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         (ii)  any requirement by the Employer that the Employee's position and
               principal office be based and located more than twenty (20) miles
               outside the boundaries of the City of Montreal;

         (iii) any change in the Employee's title, reporting relationship,
               responsibilities or authority as in effect immediately prior to
               any Change of Control which is made within twenty-four (24)
               months of such Change of Control and which adversely affects to a
               material degree his role in the management of the Employer.

         (iv)  any reduction in the Employee's salary paid to him by the
               Employer as in effect immediately prior to any Change of Control
               or, if such salary has been subsequently increased at any time or
               from time to time, any reduction in such increased salary;

         (v)   any termination or reduction in value of the Employee's employee
               benefit programs, including, but not limited to, any pension
               plan, stock option plan, investment plan, savings plan, incentive
               compensation plan or life insurance, medical plans or disability
               plans provided by the Employer to the Employee and in which the
               Employee is participating or under which the Employer is covered,
               all as in effect immediately prior to any Change of Control; and

         (vi)  any failure or refusal of the Employer to renew the Termination
               Benefits under this Agreement as outlined in Section 19.2 after
               any Change of Control shall have occurred.

(l)  "PERMITTED USES" shall mean the analysis and utilization of Confidential
     Information by the Employee in relation to any Activity for purposes of
     fulfilling and executing the Employee's duties, responsibilities and
     functions hereunder.

(m)  "PERSON" shall mean any individual or other entity possessed of judicial
     personality, including, without limitation, a corporation, company,
     cooperative, partnership, trust, unincorporated association, Affiliate or
     Governmental Body; and pronouns when they refer to a Person shall have a
     similarly extended meaning.

(n)  "TERMINATION BENEFITS" shall mean the rights and benefits in favour of the
     Employee provided for under Article 17 of this Agreement as well as the
     obligations of the Employer under the said Article.

(o)  "TERRITORY" shall mean North America, as well as any other country in which
     the Employer may carry on business at any time during the one (1) year
     period following the date of termination of this Agreement.



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                                   ARTICLE 2.
                                      TERM

2.1  Term. This Agreement is hereby concluded for a term of five (5) years,
effective as of the date hereof.

                                   ARTICLE 3.
                          DUTIES AND RESPONSIBILITIES

3.1  Duties and Responsibilities. As Chairman of the Board, President and Chief
Executive Officer of the Employer, the Employee's duties and responsibilities
shall include, above and beyond those inherent to the Employee's office and
normally pertaining to it, those compatible with the Employee's position and
which the Employer or its Board of Directors or the Board of Directors of
ClinTrials Research, Inc. may delegate to the Employee from time to time.

3.2  Additional Duties. The Employee hereby agrees to execute such additional
tasks compatible with his position as may be assigned by the Employer from time
to time, the whole according to the directives of the Employer.

                                   ARTICLE 4.
                                    LOYALTY

4.1  Loyalty. The Employee shall devote the whole of his working time,
attention, skills and competence to the Employer and to the Business. The
Employee shall act with diligence, loyalty and honesty and shall make all
necessary efforts to promote the Employer's legitimate interests for the term
of this Agreement.

                                   ARTICLE 5.
                                CONFIDENTIALITY

5.1  Obligation of Confidentiality. The Employee hereby agrees not to, use,
divulge, diffuse, sell, transfer, give, circulate, or otherwise distribute to
any Person, or otherwise make public, any Confidential Information during the
term of this Agreement and for a period of thirty-six (36) months following the
termination of this Agreement.

5.2  Trade Secrets. Notwithstanding any provisions of this Agreement to the
contrary, the Employee shall not, at any time while an employee of the Employer
or at any time thereafter, use, divulge, diffuse, sell, transfer, give,
circulate or otherwise distribute to any Person Confidential Information which
constitutes a trade secret of the Employer.


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5.3  Exception. Notwithstanding any provision hereof to the contrary, the
Employee shall have the right to use Confidential Information in relation to
Permitted Uses; in which event, the Employee shall, at all times, take all
necessary, useful or desirable measures in order to prevent the disclosure or
non-authorized use of such Confidential Information.

5.4  No Unauthorized Reproductions. Except when authorized in accordance with
the Permitted Uses, under no circumstances shall the Employee reproduce any
Confidential Information without the Employer's prior written consent. All
reproductions of Confidential Information shall be governed by this Agreement
and shall be treated as Confidential Information hereunder.

5.5  Return of Confidential Information. All Confidential Information and all
Embodiments thereof (including any reproductions) shall remain the sole property
of the Employer and shall be returned to the Employer immediately upon request
to this effect or immediately after the termination of this Agreement.

5.6  Exceptions. Notwithstanding any provision hereof to the contrary, nothing
in this Agreement shall prevent the disclosure of Confidential Information if
such disclosure must be made in response to the formal request of a Governmental
Body or is otherwise required under any applicable law; it being understood,
however, that to the extent possible, the Employee shall inform the Employer of
such a request for disclosure in order that the latter may, at the appropriate
time, decide whether or not the contest the said disclosure. The Employee shall
fully cooperate with the Employer in any efforts to obtain any type of
protective order or any other remedy or recourse which the Employer may seek to
obtain in this regard.


                                   ARTICLE 6.
               OBLIGATION OF NON-COMPETITION AND NON-SOLICITATION

6.1  Obligation of Non-Competition. The Employee shall not, during the term of
this Agreement and, on condition that the Employee receives payment of the
Termination Benefits as a result of an Involuntary Termination, for a period
of thirty-six (36) months after the date of termination of the Employee's
employment, on the Employee's own behalf or on behalf of any Person, whether
directly or indirectly, in any capacity whatsoever, whether alone, through or
in connection with any Person, carry on or be engaged in or have any financial
or other interest in or be otherwise commercially involved in any endeavor,
activity or business in all or part of the Territory which is in competition,
in whole or in part, with the Business.

6.2  Exception. The Employee shall not be in default under this Article by
virtue of the Employee holding, strictly for portfolio purposes and as a passive
investor, no more than five percent (5%) of the issued and outstanding shares of
any body corporate which is listed on a recognized stock exchange, the business
of which body corporate is in competition, in whole or in part, with the
Business.



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6.3  Obligations of Non-Solicitation. The Employee shall not, during the term of
this Agreement and, on condition that the Employee receives payment of the
Termination Benefits as a result of an Involuntary Termination, for a period of
thirty-six (36) months after the date of termination of the Employee's
employment, solicit the employment or other services of any employee of the
Employer.

                                   ARTICLE 7.
                                     SALARY

7.1  Salary. The Employee shall receive an annual gross base salary of two
hundred and twenty thousand dollars Canadian ($220,000) (the "Base Salary"),
less the appropriate legal deductions, to be paid in twenty-six (26) bi-weekly
and equal instalments. Such salary shall be reviewed annually by the
Compensation Committee of the Employer in accordance with its internal policies
in effect from time to time but shall not, at any time, be reduced to less than
two hundred and twenty thousand dollars Canadian ($220,000).

                                    ARTICLE 8.
                           BONUS AND INCENTIVE PLANS

8.1  Bonus and Incentive Plans. The Employee shall be eligible to participate in
all of the Employer's bonus and incentive compensation plans in force and
offered to senior executives of the Employer at the time, which plans may be
modified by the Employer at its sole discretion from time to time.

                                   ARTICLE 9.
                             BENEFITS AND VACATION

9.1  Benefits and Vacation. The Employee shall have the right to participate in
all benefit programs and/or plans granted to senior executives of the Employer,
the whole in accordance with the actual programs or plans that the Employer may
institute from time to time or as otherwise required under any applicable law.
The Employee shall be granted vacation in accordance with the Employer's policy
as amended from time to time, which at the date of signing of the present
Agreement is the following: four (4) weeks of vacation after fifteen (15) years
of uninterrupted service and five (5) weeks of vacation after twenty (20) years
of uninterrupted service.

                                  ARTICLE 10.
                                    EXPENSES

10.1  Expenses. The Employer hereby agrees to reimburse to the Employee all
expenses and fees reasonably incurred by the Employee in the exercise of the
Activities upon presentation of appropriate receipts or other evidence thereof.

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                                   ARTICLE 11.
                                   AUTOMOBILE

11.1 Automobile. The Employee shall be entitled during the term of the
Agreement to the use of one (1) automobile vehicle fully expensed by the
Employer and commensurate to the Employee's position.

                                   ARTICLE 12.
                                CLUB MEMBERSHIPS

12.1 Club Memberships. The Employee shall be entitled to membership in the
Forest and Stream Club, the West Island Health Club and in any other club(s) or
associations selected by the Employee and acceptable to the Employer, whereupon
all membership fees and dues shall be paid by the Employer and the ownership of
which shall be the property of the Employee.

                                   ARTICLE 13.
                                 STOCK OPTIONS

13.1 Stock Options. The Employee shall be eligible to participate in and
benefit from any stock option and/or stock purchase plan that is offered or
adopted by ClinTrials Research, Inc. for the benefit of its senior executives
and key employees, the whole in accordance with the terms and conditions of
such a plan, as approved and modified from time to time by the Board of
Directors of ClinTrials Research, Inc.

                                   ARTICLE 14.
                                PENSION BENEFITS

14.1 Pension Benefits. The Employee shall continue to participate in and
benefit from the existing Pension Plan for Designated Employees of Employer. In
accordance with the terms and conditions of the said plan, as approved and
modified from time to time by the Board of Directors of the Employers. This
Agreement does not affect Employee's pension rights under existing pension
agreements.

                                   ARTICLE 15.
                          TERMINATION OF THE AGREEMENT

15.1 Termination of the Agreement. The parties hereto acknowledge and expressly
agree that the present Agreement may only be terminated in any of the following
eventualities:

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(a)  at any time, for fraud or gross misconduct, on simple notice from the
     Employer to the Employee, the whole without other notice or any pay in lieu
     of notice or any indemnity whatsoever, except as may otherwise be required
     by applicable law; or

(b)  at any time for any reason other than fraud or gross misconduct, by
     remitting to the Employee the amounts and benefits referred to in section
     17.2, applied mutatis mutandis, whether or not there is a Change of
     Control; or

(c)  at any time in accordance with Article 17; or

(d)  upon the death or the Incapacity of the Employee.


                                  ARTICLE 16.
                         OBLIGATION TO REMAIN EMPLOYED

16.1 Employee to Remain Employed. If a Person takes any steps to effect a
Change of Control, the Employee shall not voluntarily leave his employment with
the Employer, other than by way of normal retirement, and shall continue to
perform his duties related to his employment until such person has abandoned or
terminated his or its efforts to effect a Change of Control or until after a
Change of Control has been effected, except as may be permitted by other
provisions of this agreement.


                                  ARTICLE 17.
                              TERMINATION BENEFITS

17.1 Conditions of Payment. The benefits outlined in Section 17.2 shall become
due and payable if:

(a)  there has been a Change of Control of the Employer; and

(b)  the employment of the Employee with the Employer has been terminated by an
     Involuntary Termination;

but, subject to Section 17.7 hereof, no such benefits shall be payable in
relation to any particular Change of Control if within twenty-four (24) months
next following that particular Change of Control, the employment of the
Employee with the Employer has not been terminated by an Involuntary
Termination.

17.2 Termination Benefits. If the events outlined in Section 17.1 have occurred,
the Employer shall:



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(a) pay to the Employee on the same basis as in effect immediately prior to such
    Involuntary Termination for a period of three (3) years following such
    Involuntary Termination an amount equivalent to the Employee's salary and
    Bonus at the rate in effect immediately prior to such Involuntary
    Termination or on the effective date of the Change of Control, whichever is
    higher;

(b) pay to the Employee within sixty (60) days following the end of the fiscal
    year of the Employer in which the Involuntary Termination occurs, a lump sum
    equivalent to the amount, if any, of such Bonus which would otherwise have
    been payable to the Employee had he remained employed to the end of such
    fiscal year, calculated on the basis that the number of months, including
    the month in which such Involuntary Termination occurs, bears to the total
    number of months for which the Bonus would otherwise have been paid during
    such fiscal year and calculated in accordance with the terms for Bonus
    payments as in effect immediately prior to such Involuntary Termination or
    on the effective date of the Change of Control, whichever would yield a
    higher Bonus payment to the Employee;

(c) pay to the Employee the amount of any unpaid salary earned by the Employee
    up to and including the date of such Involuntary Termination;

(d) pay to the Employee any unpaid vacation pay earned by him up to and
    including the date of such Involuntary Termination;

(e) continue to make the employer contributions necessary to maintain the
    Employee's coverage pursuant to all benefit plans provided to the Employee
    by the Employer immediately prior to such Involuntary Termination or on the
    effective date of the Change of Control, whichever is more beneficial to the
    Employee, for a period of three (3) years following such Involuntary
    Termination and shall deduct from any payments payable to the Employee
    pursuant to Subsection 17.2(a) hereof the amount of any employee
    contributions necessary to maintain such coverage for the above-noted period
    based on any such contributions which were in effect immediately prior to
    such Involuntary Termination or on the effective date of the Change of
    Control, whichever are lower;

(f) pay to the Employee an amount equivalent to the leasing cost of any car
    provided by the Employer to the Employee and any operating expenses of such
    car paid for by the Employer, all as in effect immediately prior to such
    Involuntary Termination or on the effective date of the Change of Control,
    whichever is more beneficial to the Employee, for a period of three (3)
    years following such Involuntary Termination;

(g) pay to the Employee for a period of three (3) years following such
    Involuntary Termination the amount of any annual club dues and club expenses
    paid for by the Employer on behalf

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    of the Employee immediately prior to such Involuntary Termination or on the
    effective date of the Change of Control, whichever is more beneficial to the
    Employee;

(h) in respect of all stock options granted to Employee under any stock option
    plan in effect immediately prior to such Involuntary Termination whether or
    not such options are currently exercisable all options shall vest, and
    remain exercisable for a six (6) month period following Termination.

(i) credit the Employee with service for the purposes of any pension plan or
    pension arrangements in which the Employee participated or which pertained
    to the Employee immediately prior to such Involuntary Termination or which
    were in effect on the effective date of the Change of Control, whichever
    were more beneficial to the Employee, for the period of three (3) years
    following such Involuntary Termination and include in calculating the
    Employee's earnings for the purpose of determining any benefits payable to
    the Employee pursuant to such plan or arrangements all amounts (other than
    any Bonus) payable to the Employee pursuant to Subsection 17.2(a);

(j) until the Employee accepts a position of substantially similar character and
    compensation in the industry, his Retirement Compensation Arrangement (or
    supplementary pension plan) with the Employer will be properly funded
    annually, for past services, on the basis of the information set forth in
    the letter of Towers Perrin dated November 16, 1990, a copy of which is
    annexed hereto as Appendix "A";

(k) until the Employee accepts a position of substantially similar character and
    compensation in the industry, his pension plan will continue to be available
    and fully paid-up, on the basis of the information set forth in the letter
    of Towers Perrin dated November 16, 1990, copy attached, until the Employee
    attains the age of sixty (60), as though the Employee's employment with the
    Employer was uninterrupted until that time;

(l) proper Arrangements satisfactory to the parties will be made at the time of
    termination of the Employee's employment by an Involuntary Termination so as
    to secure the payment of all sums due to him; and

(m) should the Employee accept alternative work outside Quebec, Employee shall
    use his best efforts to cause his new employer to pay moving expenses, and
    failing that, then the Employee will also be reimbursed for unreimbursed
    moving expenses up to twenty thousand dollars ($20,000).

17.3 Successor. The Employer shall use its best efforts to require any
successor, whether direct or indirect, to all or substantially all of the
business and/or assets of the Employer to expressly agree to assume and to
perform this Agreement in the same manner that the Employer would have been

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<PAGE>
required to perform it if no such succession had occurred. If the Employer
fails to obtain such agreement prior to the effective date of such succession,
such failure shall be deemed to be an involuntary Termination of the Employee's
employment by the Employer and such termination shall be deemed to have
occurred on the said effective date.

17.4 Mitigation. Following an Involuntary Termination of the Employee's
employment with the Employer after a Change of Control the Employee shall use
all reasonable efforts to mitigate any damages resulting from such Involuntary
Termination provided, however, that the Employee shall not be required to
accept a position of substantially different character than the position held
by him with the Employer immediately prior to such Involuntary Termination or
on the effective date of the Change of Control, whichever was a more
responsible position, nor shall he be required to accept a position in a
location which is unreasonable, given the personal circumstances of the
Employee at the time any such position is offered to him.

17.5 Lump Sum Payment. Notwithstanding any other provisions in this Agreement,
if the Employee successfully mitigates any damages as outlined in Section 17.4
within the period of three (3) years following such Involuntary Termination:

(a)  the Employer's obligations pursuant to Subsections 17.2(a), (e), (f) and
     (g) shall thereupon cease;

(b)  the Employee shall immediately notify the Employer of such mitigation; and

(c)  following receipt of such notice, the Employer shall pay to the Employee a
     lump sum equivalent to the balance of the payment which it would otherwise
     have made to the Employee pursuant to Subsection 17.2(a) but for such
     mitigation.

17.6 Fair and Reasonable. The parties confirm that the provisions of this
Article 17 are reasonable and that the total benefits payable as outlined
herein are reasonable estimates of the damages which will be suffered by the
Employee in the event of an Involuntary Termination following a Change of
Control.

17.7 Other Rights Not Affected. The lapse of rights under Section 17.1 with
respect to any particular Change of Control shall not limit the entitlement of
the Employee to benefits becoming due and payable with in twenty-four (24)
months next following any subsequently Change of Control.


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                                  ARTICLE 18.
                                  LIMITATION

18.1  Limitation. The Employee hereby recognizes and accepts that the Employer
shall not, under any circumstances, be responsible of any additional amount,
indemnity in lieu of notice, severance pay or other damages arising from the
termination of this Agreement, above and beyond the amounts specifically
provided for herein.

                                  ARTICLE 19.
                    TERM AND RENEWAL OF TERMINATION BENEFITS

19.1  Term of Termination Benefits. Notwithstanding anything to the contrary
contained in this Agreement, the Termination Benefits under this Agreement shall
extend for an initial period of five (5) years, commencing on the date hereof.

19.2  Offer to Renew by Employer. The Employer may offer to renew the
Termination Benefits under this Agreement for a period of Five (5) years and so
on for successive periods of five (5) years each (a "Renewal Period") by giving
notice in writing to the Employee by not later than the    day of July, 2001 or
the last day of any Renewal Period, as applicable.

19.3  Non-Renewal. If the Employer offers to renew the Termination Benefits
under this Agreement and the Employee does not accept such offer, then the
Termination Benefits under this Agreement shall terminate on the    day of
July, 2001 or on the last day of the applicable Renewal Period, as the case may
be. In the event Employer does not intend to renew this Agreement or the
Termination Benefits at the end of the initial period of five (5) years, the
Employer shall give notice to Employee of its present intention not to so renew
on or before six months from the fifth anniversary hereof. In the event that
Employer does not renew this Agreement beyond the initial term of five years,
Employer shall pay Employee upon termination of this Agreement a lump sum of
money equal to Employee's most recent annual base salary as a severance payment.

                                  ARTICLE 20.
                                    GENERAL

20.1  Number. In this Agreement, words importing the singular number only shall
include the plural and vice versa, and words importing the masculine gender
shall include the feminine and neuter genders and vice versa, and words
importing persons shall include individuals, partnerships, associations,
trusts, unincorporated organizations and corporations.

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<PAGE>
20.2   Benefits of Agreement. This Agreement shall enure to the benefit of and
be binding upon the heirs, executors, administrators and legal personal
representatives of the Employee as well as the successors and permitted assigns
of the Employers.

20.3   Entire Agreement. This Agreement constitutes the entire agreement between
the parties with respect to the subject matter hereof and cancels and supersedes
any prior understandings and agreements between the parties hereto with respect
thereto. There are no representations, warranties, forms, conditions,
undertakings or collateral agreements, express, implied or statutory between the
parties with respect to the subject matter dealt with herein other than as
expressly set forth in this Agreement.

20.4   Amendments and Waivers. No amendment to this Agreement shall be valid or
binding unless set forth in writing and duly executed by both of the parties
hereto. No waiver of any breach of any provision of this Agreement shall be
effective or binding unless made in writing and signed by the party purporting
to give the same and, unless otherwise provided in the written waiver, shall be
limited to the specific breach waived.

20.5   Severability. If any provision of this Agreement is determined to be
invalid or unenforceable, in whole or in part, such invalidity or
unenforceability shall attach only to such provision or part thereof and the
remaining part of such provision and all other provisions hereof shall continue
in full force and effect.

20.6   Notices. Any notice consent, authorization, direction or other
communication required or permitted to be given hereunder shall be in writing
and shall be delivered either by personal delivery or by telex, telecopier or
similar telecommunications device and addressed as follows:

(a)    in the case of the Employee, to:

       3 Kirkland Avenue
       Beaconsfield, Quebec H9W SL1 Canada

       Attention: Michael Ankcorn

       Fax:  (514) 630-8239

(b)    in the case of the Employer, to:

       ClinTrials BioResearch Ltd.

       Care of:




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     ClinTrials Research, Inc.
     One Burton Hills Blvd., Suite 210
     Nashville, TN 37215
     Attention: Chief Executive Officer

     Copy:     Harwell Howard Hyne Gabbert & Manner, P.C.
               1800 First American Center
               315 Deaderick Street
               Nashville, Tennessee 37238
               Attention: Mark Manner

Any notice, consent, authorization, direction or other communication delivered
as aforesaid shall be deemed to have been effectively delivered and received,
if sent by telex, telecopier or similar telecommunications device, on the
calendar day next following receipt of such transmission or, if delivered, to
have been delivered and received on the date of such delivery, provided,
however, that if such date is not a business day, then it shall be deemed to
have been delivered and received on the business day next following such
delivery. Either Party may change its address for service by notice delivered
as aforesaid.

20.7 Governing Laws. This Agreement shall be governed by and construed in
accordance with the laws of the Province of Quebec.

20.8 Arbitration. Any dispute, controversy or claim arising out of, or relating
to this Agreement, or the breach, interpretation, termination or invalidity
thereof (hereinafter "Dispute"), shall be definitely settled in accordance
with the provisions on arbitration in the Code of Civil Procedure of Quebec and
the Civil Code of Quebec by a tribunal of three (3) arbitrators. Each party
shall appoint one arbitrator.

(a)  The party wishing to initiate arbitration (hereinafter "Claimant") shall
     send a notice of arbitration (hereinafter "Notice") to the other party
     (hereinafter "Respondent"), specifying the object of the Dispute and naming
     the Arbitrator of its choice.

(b)  The Respondent will then have fifteen (15) calendar days to notify the
     Claimant of its choice of arbitrator.

(c)  The two arbitrators thus appointed by the parties shall together, within
     thirty (30) days of the receipt by the Claimant of the Respondent's notice
     of its choice of arbitrator, designate the third (3rd) arbitrator who shall
     preside over the Arbitration Tribunal.

(d)  The presiding arbitrator shall be a member of the Quebec Bar with at least
     ten (10) years experience in the field of labor relations and employment
     law.

                                       15

<PAGE>
(e)    If the two arbitrators appointed by the parties are unable to agree on
       the selection of the third arbitrator within thirty (30) days of the
       receipt by the Claimant of the Respondent's Notice of its choice of
       arbitrator, the third arbitrator shall be designated by the highest
       ranking officer of the Quebec National and International Commercial
       Arbitration Centre upon a motion of either party hereto.

(f)    The seat of arbitration shall be Montreal, Canada and the language of
       arbitration shall be English. The arbitral tribunal may, without changing
       the seat of arbitration, hold hearings elsewhere for reasons of
       convenience, but only with the agreement of the parties.

20.9   COPY OF AGREEMENT. The Employee hereby acknowledges receipt of a copy of
this Agreement duly signed by the Employer.

20.10  COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which when so executed shall be deemed an original, and
such counterparts together shall constitute one and the same instrument.

20.11  LANGUAGE. The parties hereto acknowledge that they have requested and
are satisfied that this Agreement and all related documents be drawn up in the
English language. Les parties our presentes reconnaisset avoir requis que lo
presenta enpense et les documents qui y sont retorifs soient rediges an langue
anglaise.





                                       16

<PAGE>
     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date first hereinabove mentioned.


                                             /s/ Michael F. Ankcorn
                                             ---------------------------------
                                             MICHAEL F. ANKCORN


                                             CLINTRIALS BIORESEARCH LTD.


                                             Per: /s/ William C. O'Neil, Jr.
                                                  -----------------------------
                                                  Name: William C. O'Neil, Jr.







                                       17
<PAGE>
ADDENDUM TO EXECUTIVE EMPLOYMENT AGREEMENT OF JULY 31, 1996 AND THE MEMORANDUM
OF AGREEMENT OF JUNE 19, 1997 AS ENTERED INTO BY CLINITRIALS BIORESEARCH LTD.
AND MICHAEL F. ANKCORN
-------------------------------------------------------------------------------


BY AND BETWEEN:     MICHAEL F. ANKCORN

                    (hereinafter referred to as the "Employee")

AND:                CLINTRIALS BIORESEARCH LTD.

                    (hereinafter referred to as the "Employer")

WHEREAS the Employee and Employer have agreed to modify certain terms of the
Executive Employment Agreement of July 31, 1996, and the Memorandum of
Agreement of June 19, 1997, to which they are both party;

AND WHEREAS the parties agree that all terms and conditions of the Executive
Employment Agreement and Memorandum of Agreement not addressed by the present
Addendum shall remain unchanged;

NOW THEREFORE the parties hereto agree as follows:

1.   The preamble forms an integral part of the present Addendum;

2.   Article 1.1(f) of the Executive Employment Agreement is hereby abolished
     and all references to "Change of Control" as defined therein are hereby
     rendered without effect;

3.   Article 1.1(o) of the Executive Employment Agreement is hereby modified by
     replacing the words "three (3)" with the words "one (1)";

4.   Article 6.1 of the Executive Employment Agreement is hereby modified by
     replacing the words "thirty-six (36)" with the words "twelve (12)";

5.   Article 6.3 of the Executive Employment Agreement is hereby modified by
     replacing the words "thirty-six (36)" with the words "twelve (12)";








<PAGE>

6.   Article 17 of the Executive Employment Agreement including all of its
     sections, paragraphs, sub-paragraphs and other constituent elements, is
     hereby abolished as it pertains to termination of the Employee's employment
     following a Change of Control only, as that term was defined in the
     Executive Employment Agreement prior to the present modifications and all
     references to the said Article 17 as they appear throughout the Executive
     Employment Agreement and the Memorandum of Agreement are hereby rendered
     without effect inasmuch as they pertain to termination following a Change
     of Control only;

7.   For greater certainty, the parties to the present Addendum hereby agree
     that the provisions of Article 17 of the Executive Employment Agreement,
     and in particular section 17.2, will continue to apply to the termination
     of the Employee's employment in accordance with the provisions of paragraph
     15.1(b) of the Executive Employment Agreement save that this provision
     will not apply in the case of a Change of Control and that all references
     to the term "three (3) years" in section 17.2 shall be replaced with the
     term "one (1) year";

8.   All other terms of the Executive Employment Agreement remain in full force
     and effect.

9.   The parties hereto acknowledge that they have requested and are satisfied
     that this Addendum be drafted in the English language. / Les parties aux
     presentes reconnaissent avoir demande que le present addenda soit redige en
     anglais.


IN WITNESS WHEREOF the parties hereto have executed this Addendum on the date
first mentioned above


                                          CLINITRIALS BIORESEARCH LTD.

                                          /s/ Paul Bancroft
                                          _____________________________________
/s/ Michael F. Ankcorn                    PAUL BANCROFT
___________________________________       _____________________________________
Michael F. Ankcorn                        Per: Vice President, Finance/Admin


29 August 2001                            29/08/01
___________________________________       _____________________________________
Date:                                     Date:
<PAGE>
      ADDENDUM TO EXECUTIVE EMPLOYMENT AGREEMENT OF JULY 31, 1996 AND THE
      MEMORANDUM OF AGREEMENT OF JUNE 19,1997 AS ENTERED INTO BY CLINTRIALS
                     BIORESEARCH LTD. AND MICHAEL F. ANKCORN


BY AND BETWEEN:          MICHAEL F. ANKCORN
                         (hereinafter referred to as the "Employee")

AND:                     CLINTRIALS BIORESEARCH LTD.
                         (hereinafter referred to as the "Employer")

DATED AS OF JUNE 3, 2002

WHEREAS, the Employee and the Employer have agreed to acknowledge and to modify
certain terms of the Executive Employment Agreement of July 31, 1996, and the
Memorandum of Agreement of June 19, 1997, to which they are both party;

AND WHEREAS, the parties agree that the terms used in this Addendum that are not
otherwise defined shall have the meanings given to such terms in the Executive
Employment Agreement;

AND WHEREAS, the parties agree that all terms and conditions of the Executive
Employment Agreement and Memorandum of Agreement not addressed or modified by
this Addendum of any prior Addendum between the parties shall remain unchanged;

NOW THEREFORE, the parties hereto agree as follows:

1. The parties acknowledge that in accordance with Article 19, Section 19.1 of
the Executive Employment Agreement, the Employer provided the appropriate notice
to the Employee on or prior to July 24, 2001 and that the first Renewal Period
and correspondingly the term of the Executive Employment Agreement set forth in
Article 2, Section 2.1 of the Executive Employment Agreement shall expire on
July 24, 2006.

2. Article 7, Section 7.1 of the Executive Employment Agreement is hereby
modified by replacing the words and numbers "two hundred and twenty thousand
dollars Canadian ($220,000)" with the words and numbers "three hundred seventy
thousand eight hundred sixty-three dollars Canadian ($370,863)" in each
instance.

3. The parties acknowledge that Mr. Ankcorn shall continue to serve Employer in
his current capacities as Chairman of the Board, President and Chief Executive
Officer and that he shall also be employed as a Group Executive Vice President
of Inveresk Research Group, Inc., the Employer's newly formed indirect parent
company.

4. All other terms of the Executive Employment Agreement remain in full force
and effect.

5. The parties hereto acknowledge that they have requested and are satisfied
that this Addendum be drafted in English language. / Les parties aux presentes
reconnaissent avoir demande que le present addenda soit redige en anglais.
<PAGE>
IN WITNESS WHEREOF the parties hereto have executed this Addendum on the date
first mentioned above.

                                            CLINTRIALS BIORESEARCH LTD.


/s/ Michael F. Ankcorn                       /s/ Paul Bancroft
-------------------------                   ---------------------------
Name: Michael F. Ankcorn                     Name: Paul Bancroft
                                             Title: Vice President,
                                                    Finance/Admin.