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                                                             EXHIBIT 10.54



                         QUINTILES TRANSNATIONAL CORP.
                          COMMON STOCK, $.01 PAR VALUE
                             UNDERWRITING AGREEMENT
                            (INTERNATIONAL VERSION)

                                                                   March 6, 1997


Goldman Sachs International
Morgan Stanley & Co. International Limited
Smith Barney Inc.
William Blair & Company, L.L.C.
  As representatives of the several Underwriters
  named in Schedule I hereto,
c/o Goldman Sachs International,
Peterborough Court,
133 Fleet Street,
London EC4A 2BB, England.

Ladies and Gentlemen:

    Quintiles Transnational Corp., a North Carolina corporation (the "Company"),
proposes, subject to the terms and conditions stated herein, to issue and sell
to the Underwriters named in Schedule I hereto (the "Underwriters") an aggregate
of 283,000 shares of Common Stock, $.01 par value ("Stock") of the Company and
the shareholders of the Company named in Schedule II hereto (the "Selling
Shareholders") propose, subject to the terms and conditions stated herein, to
sell to the Underwriters an aggregate of 677,000 shares and, in the case of
certain Selling Shareholders identified with an asterisk in Schedule II hereto
and at the election of the Underwriters, up to 144,000 additional shares of
Stock.  The aggregate of 960,000 shares to be sold by the Company and the
Selling Shareholders is herein called the "Firm Shares" and the aggregate of
144,000 additional shares to be sold by the Selling Shareholders identified with
an asterisk in Schedule II hereto is herein called the "Optional Shares".  The
Firm Shares and the Optional Shares which the Underwriters elect to purchase
pursuant to Section 2 hereof are herein collectively called, the "Shares".

    It is understood and agreed to by all parties that the Company and the
Selling Shareholders are concurrently entering into an agreement, a copy of
which is attached hereto (the "U.S. Underwriting Agreement"), providing for the
sale by the Company and the Selling Shareholders of up to a total of 4,416,000
shares of Stock (the "U.S. Shares"), including the overallotment option
thereunder, through arrangements with certain underwriters in the United States
(the "U.S. Underwriters"), for whom Goldman, Sachs & Co., Morgan Stanley & Co.
Incorporated, Smith Barney Inc. and William Blair & Company, L.L.C. are acting
as representatives.  Anything herein or therein to the contrary notwithstanding,
the respective closings under this Agreement and the U.S. Underwriting Agreement
are hereby expressly

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made conditional on one another.  The Underwriters hereunder and the U.S.
Underwriters are simultaneously entering into an Agreement between U.S. and
International Underwriting Syndicates (the "Agreement between Syndicates")
which provides, among other things, for the transfer of shares of Stock between
the two syndicates and for consultation by the Lead Manager hereunder with
Goldman, Sachs & Co. prior to exercising the rights of the Underwriters under
Section 7 hereof.  Two forms of prospectus are to be used in connection with
the offering and sale of shares of Stock contemplated by the foregoing, one
relating to the Shares hereunder and the other relating to the U.S. Shares.
The latter form of prospectus will be identical to the former except for
certain substitute pages as included in the registration statement and
amendments thereto as mentioned below.  Except as used in Sections 2, 3, 4, 9
and 11 herein, and except as context may otherwise require, references
hereinafter to the Shares shall include all of the shares of Stock which may be
sold pursuant to either this Agreement or the U.S. Underwriting Agreement, and
references herein to any prospectus whether in preliminary or final form, and
whether as amended or supplemented, shall include both the U.S. and the
international versions thereof.

    In addition, this Agreement incorporates by reference certain provisions
from the U.S. Underwriting Agreement (including the related definitions of
terms, which are also used elsewhere herein) and, for purposes of applying the
same, references (whether in these precise words or their equivalent) in the
incorporated provisions to the "Underwriters" shall be to the Underwriters
hereunder, to the "Shares" shall be to the Shares hereunder as just defined, to
"this Agreement" (meaning therein the U.S. Underwriting Agreement) shall be to
this Agreement (except where this Agreement is already referred to or as the
context may otherwise require) and to the representatives of the Underwriters or
to Goldman, Sachs & Co. shall be to the addressees of this Agreement and to
Goldman Sachs International ("GSI"), and, in general, all such provisions and
defined terms shall be applied mutatis mutandis as if the incorporated
provisions were set forth in full herein having regard to their context in this
Agreement as opposed to the U.S. Underwriting Agreement.

    1.   The Company and each of the several Selling Shareholders hereby make
to the Underwriters the same respective representations, warranties and
agreements as are set forth in Section 1 of the U.S. Underwriting Agreement,
which Section is incorporated herein by this reference.

    2.   Subject to the terms and conditions herein set forth, (a) each Selling
Shareholder agrees that the purchase price per share at which the Underwriters
will purchase Shares from such Selling Shareholder (as set forth in clause (b)
below) shall be the same as the purchase price per share at which the Company
sells shares to be purchased by the Underwriters from the Company hereunder,
(b) the Company and each of the Selling Shareholders agree, severally and not
jointly, to sell to each of the Underwriters, and each of the Underwriters
agrees, severally and not jointly, to purchase from the Company and each of the
Selling Shareholders, at a purchase price per share of $60.355, the number of
Firm Shares (to be adjusted by you so as to eliminate fractional shares)
determined by multiplying the aggregate number of Firm Shares to be sold by the
Company and each of the Selling Shareholders as set forth opposite their
respective names in Schedule II hereto by a fraction, the numerator of which is
the aggregate number of Firm Shares to be purchased by such Underwriter as set
forth opposite the name of such Underwriter in Schedule I hereto and the
denominator of


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which is the aggregate number of Firm Shares to be purchased by all the
Underwriters from the Company and all the Selling Shareholders hereunder and
(c) in the event and to the extent that the Underwriters shall exercise the
election to purchase Optional Shares as provided below, each of the Selling
Shareholders identified with an asterisk in Schedule II hereto, agrees,
severally and not jointly, to sell to each of the Underwriters, and each of the
Underwriters agrees, severally and not jointly, to purchase from each of the
Selling Shareholders, at the purchase price per share set forth in clause (b)
of this Section 2, that portion of the number of Optional Shares as to which
such election shall have been exercised (to be adjusted by you so as to
eliminate fractional shares) determined by multiplying such number of Optional
Shares by a fraction the numerator of which is the maximum number of Optional
Shares which such Underwriter is entitled to purchase as set forth opposite the
name of such Underwriter in Schedule I hereto and the denominator of which is
the maximum number of Optional Shares that all of the Underwriters are entitled
to purchase hereunder.

    The Selling Shareholders identified with an asterisk in Schedule II hereto,
hereby grant, severally and not jointly, to the Underwriters the right to
purchase at their election up to 144,000 Optional Shares, at the purchase price
per share set forth in the paragraph above, for the sole purpose of covering
overallotments in the sale of the Firm Shares.  Any such election to purchase
Optional Shares shall be made in proportion to the maximum number of Optional
Shares to be sold by each Selling Shareholder as set forth in Schedule II
hereto. Any such election to purchase Optional Shares may be exercised only by
written notice from you to the Attorneys-in-Fact, given within a period of 30
calendar days after the date of this Agreement and setting forth the aggregate
number of Optional Shares to be purchased and the date on which such Optional
Shares are to be delivered, as determined by you but in no event earlier than
the First Time of Delivery (as defined in Section 4 hereof) or, unless you and
the Attorneys-in-Fact otherwise agree in writing, earlier than two or later
than ten business days after the date of such notice.

    3.   Upon the authorization by GSI of the release of the Firm Shares, the
several Underwriters propose to offer the Firm Shares for sale upon the terms
and conditions set forth in the Prospectus and in the forms of Agreement among
Underwriters (International Version) and Selling Agreements, which have been
previously submitted to the Company and the Selling Shareholders by you.  Each
Underwriter hereby makes to and with the Company and the Selling Shareholders
the representations and agreements of such Underwriter as a member of the
selling group contained in Sections 3(d) and 3(e) of the form of Selling
Agreements.

    4.   (a)   The Shares to be purchased by each Underwriter hereunder, in
definitive form, and in such authorized denominations and registered in such
names as Goldman, Sachs & Co. may request upon at least two business days'
prior notice to the Company and the Selling Shareholders shall be delivered by
or on behalf of the Company and the Selling Shareholders to Goldman, Sachs &
Co., for the account of such Underwriter, against payment by or on behalf of
such Underwriter of the purchase price therefor in United States dollars by
wire transfer of immediately available funds to an account or accounts
designated by the Custodian and the Company.  The Company and the Selling
Shareholders will cause the certificates representing the Shares to be made
available for checking and packaging at least one full business day prior to
the Time of Delivery (as defined below) with respect thereto at the office of
Goldman, Sachs & Co., 85 Broad Street, New York, New York 10004 (the
"Designated





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Office").  The time and date of such delivery and payment shall be, with
respect to the Firm Shares, 9:30 a.m., New York City time, on March 12, 1997 on
such other time and date as Goldman, Sachs & Co. and the Company and the
Selling Shareholders may agree upon in writing, and, with respect to the
Optional Shares, 9:30 a.m., New York time, on the date specified by Goldman,
Sachs & Co. in the written notice given by Goldman, Sachs & Co. of the
Underwriters' election to purchase such Optional Shares, or such other time and
date as Goldman, Sachs & Co. and the Company and the Selling Shareholders may
agree upon in writing.  Such time and date for delivery of the Firm Shares is
herein called the "First Time of Delivery", such time and date for delivery of
the Firm Optional Shares, if not the First Time of Delivery, is herein called
the "Second Time of Delivery", and each such time and date for delivery is
herein called a "Time of Delivery".

         (b)   The documents to be delivered at each Time of Delivery by or on
behalf of the parties hereto pursuant to Section 7 of the U.S. Underwriting
Agreement, including the cross-receipt for the Shares and any additional
documents requested by the Underwriters pursuant to Section 7(k) of the U.S.
Underwriting Agreement will be delivered at the offices of Sullivan & Cromwell,
125 Broad Street, New York, New York 10004 (the "Closing Location"), and the
Shares will be delivered at the Designated Office, all at each Time of
Delivery.  A meeting will be held at the Closing Location at 2:00 p.m., New
York City time, on the New York Business Day next preceding each Time of
Delivery, at which meeting the final drafts of the documents to be delivered
pursuant to the preceding sentence will be available for review by the parties
hereto.  For the purposes of this Section 4, "New York Business Day" shall mean
each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on
which banking institutions in New York are generally authorized or obligated by
law or executive order to close.

    5.   The Company hereby makes with the Underwriters the same agreements as
are set forth in Section 5 of the U.S. Underwriting Agreement, which Section is
incorporated herein by this reference.

    6.   The Company, each of the Selling Shareholders, and the Underwriters
hereby agree with respect to certain expenses on the same terms as are set
forth in Section 6 of the U.S. Underwriting Agreement, which Section is
incorporated herein by this reference.

    7.   Subject to the provisions of the Agreement between Syndicates, the
obligations of the Underwriters hereunder shall be subject, in their
discretion, at each Time of Delivery to the condition that all representations
and warranties and other statements of the Company, and the Selling
Shareholders herein are, at and as of each Time of Delivery, true and correct,
the condition that the Company and the Selling Shareholders shall have
performed all of their respective obligations hereunder theretofore to be
performed, and additional conditions identical to those set forth in Section 7
of the U.S. Underwriting Agreement, which Section is incorporated herein by
this reference.

    8.         (a)      The Company will indemnify and hold harmless each
Underwriter against any losses, claims, damages or liabilities, joint or
several, to which such Underwriter may become subject, under the Act or
otherwise, insofar as such losses, claims, damages or liabilities (or actions in
respect thereof) arise out of or are based upon an untrue statement or alleged
untrue statement of a material fact contained in any Preliminary Prospectus, the





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Registration Statement or the Prospectus, or any amendment or supplement
thereto, or arise out of or are based upon the omission or alleged omission to
state therein a material fact required to be stated therein or necessary to
make the statements therein not misleading, and will periodically reimburse
each Underwriter for any legal or other expenses reasonably incurred by such
Underwriter in connection with investigating or defending any such action or
claim as such expenses are incurred; provided, however, that the Company shall
not be liable in any such case to the extent that any such loss, claim, damage
or liability arises out of or is based upon an untrue statement or alleged
untrue statement or omission or alleged omission made in any Preliminary
Prospectus, the Registration Statement or the Prospectus or any such amendment
or supplement in reliance upon and in conformity with written information
furnished to the Company by any Underwriter through GSI or by any Selling
Shareholder expressly for use therein; and provided, further, that the Company
shall not be liable to any Underwriter under the indemnity agreement in this
subsection (a) with respect to any Preliminary Prospectus to the extent that
any such loss, claim, damage or liability of such Underwriter results from the
fact that such Underwriter sold Shares to a person as to whom it shall be
established that there was not sent or given, at or prior to the written
confirmation of such sale, a copy of the Prospectus (excluding documents
incorporated by reference) or of the Prospectus as then amended or supplemented
(excluding documents incorporated by reference) in any case where such delivery
is required by the Act if the Company has previously furnished copies thereof
in sufficient quantity to such Underwriter and the loss, claim, damage or
liability of such Underwriter results from an untrue statement or omission of a
material fact contained in the Preliminary Prospectus which was identified in
writing prior to the date hereof to such Underwriter and corrected in the
Prospectus (excluding documents incorporated by reference) or in the Prospectus
as then amended or supplemented (excluding documents incorporated by
reference).

    (b)  Each of the Selling Shareholders will indemnify and hold harmless each
Underwriter against any losses, claims, damages or liabilities, joint or
several, to which such Underwriter may become subject, under the Act or
otherwise, insofar as such losses, claims, damages or liabilities (or actions
in respect thereof) arise out of or are based upon (i) an untrue statement or
alleged untrue statement of a material fact contained in any Preliminary
Prospectus, the Registration Statement or the Prospectus, or any amendment or
supplement thereto, or arise out of or are based upon the omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, in each case to the
extent, but only to the extent, that such untrue statement or alleged untrue
statement or omission or alleged omission was made in any Preliminary
Prospectus, the Registration Statement or the Prospectus or any such amendment
or supplement in reliance upon and in conformity with written information
furnished to the Company by such Selling Shareholder expressly for use therein,
or (ii) the failure of such Selling Shareholder at or prior to the written
confirmation of the sale of the Shares to be sold by such Selling Shareholder
to send or deliver a copy of an amended Preliminary Prospectus or Prospectus
(or the Prospectus as amended or supplemented) to the person asserting any such
losses, claims, damages or liabilities against any Underwriter, which person
purchased the Shares which are the subject thereof, and the untrue statement or
alleged untrue statement or omission or alleged omission of a material fact
made in such Preliminary Prospectus was corrected in the amended Preliminary
Prospectus or the Prospectus (or the Prospectus as amended and





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supplemented); and each Selling Shareholder will periodically reimburse each
Underwriter for any legal or other expenses reasonably incurred by such
Underwriter in connection with investigating or defending any such action or
claim as such expenses are incurred; provided, however, that the amount of such
indemnity shall be limited to the total net proceeds received by each such
Selling Shareholder from the offering of Shares purchased under this Agreement
(before deducting expenses).

    (c)  Each Underwriter will indemnify and hold harmless the Company and each
Selling Shareholder against any losses, claims, damages or liabilities to which
the Company or such Selling Shareholder may become subject, under the Act or
otherwise, insofar as such losses, claims, damages or liabilities (or actions
in respect thereof) arise out of or are based upon an untrue statement or
alleged untrue statement of a material fact contained in any Preliminary
Prospectus, the Registration Statement or the Prospectus, or any amendment or
supplement thereto, or arise out of or are based upon the omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, in each case to the
extent, but only to the extent, that such untrue statement or alleged untrue
statement or omission or alleged omission was made in any Preliminary
Prospectus, the Registration Statement or the Prospectus or any such amendment
or supplement in reliance upon and in conformity with written information
furnished to the Company by such Underwriter through GSI expressly for use
therein; and will reimburse the Company and each Selling Shareholder for any
legal or other expenses reasonably incurred by the Company or such Selling
Shareholder in connection with investigating or defending any such action or
claim as such expenses are incurred.

    (d)  Promptly after receipt by an indemnified party under subsection (a),
(b) or (c) above of notice of the commencement of any action, such indemnified
party shall, if a claim in respect thereof is to be made against an
indemnifying party under such subsection, notify the indemnifying party in
writing of the commencement thereof; but the omission so to notify the
indemnifying party shall not relieve it from any liability which it may have to
any indemnified party otherwise than under such subsection.  In case any such
action shall be brought against any indemnified party and it shall notify the
indemnifying party of the commencement thereof, the indemnifying party shall be
entitled to participate therein and, to the extent that it shall wish, jointly
with any other indemnifying party similarly notified, to assume the defense
thereof, with counsel satisfactory to such indemnified party (which shall not,
except with the consent of the indemnified party, be counsel to the
indemnifying party), and, after notice from the indemnifying party to such
indemnified party of its election so to assume the defense thereof, the
indemnifying party shall not be liable to such indemnified party under such
subsection for any legal expenses of other counsel or any other expenses, in
each case subsequently incurred by such indemnified party, in connection with
the defense thereof other than reasonable costs of investigation. No
indemnifying party shall, without the written consent of the indemnified party,
effect the settlement or compromise of, or consent to the entry of any judgment
with respect to, any pending or threatened action or claim in respect of which
indemnification or contribution may be sought hereunder (whether or not the
indemnified party is an actual or potential party to such action or claim)
unless such settlement, compromise or judgment (i) includes an unconditional
release of the indemnified party from all liability arising out of such action
or claim and (ii) does not include a statement





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as to or an admission of fault, culpability or a failure to act, by or on
behalf of any indemnified party.

    (e)  If the indemnification provided for in this Section 8 is unavailable
to or insufficient to hold harmless an indemnified party under subsection (a),
(b) or (c) above in respect of any losses, claims, damages or liabilities (or
actions in respect thereof) referred to therein, then each indemnifying party
shall contribute to the amount paid or payable by such indemnified party as a
result of such losses, claims, damages or liabilities (or actions in respect
thereof) in such proportion as is appropriate to reflect the relative benefits
received by the Company and the Selling Shareholders on the one hand and the
Underwriters on the other from the offering of the Shares.  If, however, the
allocation provided by the immediately preceding sentence is not permitted by
applicable law or if the indemnified party failed to give the notice required
under subsection (d) above, then each indemnifying party shall contribute to
such amount paid or payable by such indemnified party in such proportion as is
appropriate to reflect not only such relative benefits but also the relative
fault of the Company and the Selling Shareholders on the one hand and the
Underwriters on the other in connection with the statements or omissions which
resulted in such losses, claims, damages or liabilities (or actions in respect
thereof), as well as any other relevant equitable considerations.  The relative
benefits received by the Company and the Selling Shareholders on the one hand
and the Underwriters on the other shall be deemed to be in the same proportion
as the total net proceeds from the offering of the Shares purchased under this
Agreement (before deducting expenses) received by the Company and the Selling
Shareholders bear to the total underwriting discounts and commissions received
by the Underwriters with respect to the Shares purchased under this Agreement,
in each case as set forth in the table on the cover page of the Prospectus.
The relative fault shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission or alleged omission to state a material fact relates to information
supplied by the Company or the Selling Shareholders on the one hand or the
Underwriters on the other and the parties' relative intent, knowledge, access
to information and opportunity to correct or prevent such statement or
omission.  The Company, each of the Selling Shareholders and the Underwriters
agree that it would not be just and equitable if contributions pursuant to this
subsection (e) were determined by pro rata allocation (even if the Underwriters
were treated as one entity for such purpose) or by any other method of
allocation which does not take account of the equitable considerations referred
to above in this subsection (e).  The amount paid or payable by an indemnified
party as a result of the losses, claims, damages or liabilities (or actions in
respect thereof) referred to above in this subsection (e) shall be deemed to
include any legal or other expenses reasonably incurred by such indemnified
party in connection with investigating or defending any such action or claim.
Notwithstanding the provisions of this subsection (e), (i) no Selling
Shareholder shall be required to contribute any amount by which the total price
at which the Shares sold by such Selling Shareholder and distributed to the
public were offered to the public (before deducting expenses) exceeds the
amount of any damages that such Selling Shareholder has otherwise been required
to pay by reason of such untrue or alleged untrue statement or omission or
alleged omission, and (ii) no Underwriter shall be required to contribute any
amount in excess of the amount by which the total price at which the Shares
underwritten by it and distributed to the public were offered to the public
exceeds the amount of any damages which such Underwriter has otherwise been
required to




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<PAGE>   8


pay by reason of such untrue or alleged untrue statement or omission or alleged
omission.  No person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Act) shall be entitled to contribution from any person
who was not guilty of such fraudulent misrepresentation.  The Underwriters'
obligations in this subsection (e) to contribute are several in proportion to
their respective underwriting obligations and not joint.  The remedies provided
for in this Section 8 are not exclusive and shall not limit any rights or
remedies which may otherwise be available to any indemnified party at law or in
equity.

    (f)  The obligations of the Company and the Selling Shareholders under this
Section 8 shall be in addition to any liability which the Company and the
respective Selling Shareholders may otherwise have and shall extend, upon the
same terms and conditions, to each person, if any, who controls any Underwriter
within the meaning of the Act; and the obligations of the Underwriters under
this Section 8 shall be in addition to any liability which the respective
Underwriters may otherwise have and shall extend, upon the same terms and
conditions, to each officer and director of the Company (including any person
who, with his or her consent, is named in the Registration Statement as about
to become a director of the Company) and to each person, if any, who controls
the Company or any Selling Shareholder within the meaning of the Act.

    9.   (a)   If any Underwriter shall default in its obligation to purchase
the Shares which it has agreed to purchase hereunder at a Time of Delivery, you
may in your discretion arrange for you or another party or other parties to
purchase such Shares on the terms contained herein.  If within thirty-six hours
after such default by any Underwriter you do not arrange for the purchase of
such Shares, then the Company and the Selling Shareholders shall be entitled to
a further period of thirty-six hours within which to procure another party or
other parties satisfactory to you to purchase such Shares on such terms.  In
the event that, within the respective prescribed periods, you notify the
Company and the Selling Shareholders that you have so arranged for the purchase
of such Shares, or the Company and the Selling Shareholders notify you that
they have so arranged for the purchase of such Shares, you or the Company and
the Selling Shareholders shall have the right to postpone such Time of Delivery
for a period of not more than seven days, in order to effect whatever changes
may thereby be made necessary in the Registration Statement or the Prospectus,
or in any other documents or arrangements, and the Company agrees to file
promptly any amendments to the Registration Statement or the Prospectus which
in your opinion may thereby be made necessary. The term "Underwriter" as used
in this Agreement shall include any person substituted under this Section with
like effect as if such person had originally been a party to this Agreement
with respect to such Shares.

         (b)   If, after giving effect to any arrangements for the purchase of
the Shares of a defaulting Underwriter or Underwriters by you and the Company
and the Selling Shareholders as provided in subsection (a) above, the aggregate
number of such Shares which remains unpurchased does not exceed one-eleventh of
the aggregate number of all the Shares to be purchased at such Time of
Delivery, then the Company and the Selling Shareholders shall have the right to
require each non-defaulting Underwriter to purchase the number of Shares which
such Underwriter agreed to purchase hereunder at such Time of Delivery and, in
addition, to require each non-defaulting Underwriter to purchase its pro rata
share (based on the number of Shares which such Underwriter agreed to purchase
hereunder) of the Shares of such





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defaulting Underwriter or Underwriters for which such arrangements have not
been made; but nothing herein shall relieve a defaulting Underwriter from
liability for its default.

         (c)   If, after giving effect to any arrangements for the purchase of
the Shares of a defaulting Underwriter or Underwriters by you and the Company
and the Selling Shareholders as provided in subsection (a) above, the aggregate
number of such Shares which remains unpurchased exceeds one-eleventh of the
aggregate number of all the Shares to be purchased at such Time of Delivery, or
if the Company and the Selling Shareholders shall not exercise the right
described in subsection (b) above to require non-defaulting Underwriters to
purchase Shares of a defaulting Underwriter or Underwriters, then this
Agreement (or, with respect to the Second Time of Delivery, the obligations of
the Underwriters to purchase and of the Selling Shareholders to sell the
Optional Shares) shall thereupon terminate, without liability on the part of
any non-defaulting Underwriter or the Company or the Selling Shareholders,
except for the expenses to be borne by the Company and the Selling Shareholders
and the Underwriters as provided in Section 6 hereof and the indemnity and
contribution agreements in Section 8 hereof; but nothing herein shall relieve a
defaulting Underwriter from liability for its default.

    10.  The respective indemnities, agreements, representations, warranties
and other statements of the Company, the Selling Shareholders and the several
Underwriters, as set forth in this Agreement or made by or on behalf of them,
respectively, pursuant to this Agreement, shall remain in full force and
effect, regardless of any investigation (or any statement as to the results
thereof) made by or on behalf of any Underwriter or any controlling person of
any Underwriter, or the Company or any of the Selling Shareholders, or any
officer or director or controlling person of the Company or any controlling
person of any Selling Shareholders, and shall survive delivery of and payment
for the Shares.

    11.  In all dealings hereunder, you shall act on behalf of each of the
Underwriters, and the parties hereto shall be entitled to act and rely upon any
statement, request, notice or agreement on behalf of any Underwriter made or
given by you jointly or by GSI on your behalf; and in all dealings with any
Selling Shareholder hereunder, you and the Company shall be entitled to act and
rely upon any statement, request, notice or agreement on behalf of such Selling
Shareholder made or given by any or all of the Attorneys-in-Fact for such
Selling Shareholder.

    All statements, requests, notices and agreements hereunder shall be in
writing, and if to the Underwriters shall be delivered or sent by mail, telex
or facsimile transmission to the Underwriters in care of GSI, Peterborough
Court, 133 Fleet Street, London EC4A 2BB, England, Attention: Equity Capital
Markets, Telex No. 94012165, facsimile transmission No. (071) 774-1550; if to
any Selling Shareholder shall be delivered or sent by mail, telex or facsimile
transmission to counsel for such Selling Shareholder at its address set forth
in Schedule II hereto; and if to the Company shall be delivered or sent by
mail, telex or facsimile transmission to the address of the Company set forth
in the Registration Statement, Attention: Secretary; provided, however, that
any notice to an Underwriter pursuant to Section 8(c) hereof shall be delivered
or sent by mail, telex or facsimile transmission to such Underwriter at its
address set forth in its Underwriters' Questionnaire, or telex constituting
such Questionnaire, which address will be supplied to the Company or the
Selling





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<PAGE>   10

Shareholders by GSI upon request.  Any such statements, requests, notices or
agreements shall take effect upon receipt thereof.

    12.  This Agreement shall be binding upon, and inure solely to the benefit
of, the Underwriters, the Company and the Selling Shareholders and, to the
extent provided in Sections 8 and 10 hereof, the officers and directors of the
Company and each person who controls the Company, any Selling Shareholder or
any Underwriter, and their respective heirs, executors, administrators,
successors and assigns, and no other person shall acquire or have any right
under or by virtue of this Agreement.  No purchaser of any of the Shares from
any Underwriter shall be deemed a successor or assign by reason merely of such
purchase.

    13.  Time shall be of the essence of this Agreement.

    14.  THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH
THE LAWS OF THE STATE OF NEW YORK, UNITED STATES OF AMERICA.

    15.  This Agreement may be executed by any one or more of the parties
hereto in any number of counterparts, each of which shall be deemed to be an
original, but all such counterparts shall together constitute one and the same
instrument.

    If the foregoing is in accordance with your understanding, please sign and
return to us one for the Company and one for each of the Lead Managers or Lead
Managing Underwriters plus one for each counsel and the Custodian, if any,
counterparts hereof, and upon the acceptance hereof by you, on behalf of each
of the Underwriters, this letter and such acceptance hereof shall constitute a
binding agreement among each of the Underwriters, the Company and each of the
Selling Shareholders.  It is understood that your acceptance of this letter on
behalf of each of the Underwriters is pursuant to the authority set forth in a
form of Agreement among Underwriters (International Version), the form of which
shall be furnished to the Company and the Selling Shareholders for examination
upon request, but without warranty on your part as to the authority of the
signers thereof.





                                       10
<PAGE>   11

    Any person executing and delivering this Agreement as Attorney-in-Fact for
a Selling Shareholder represents by so doing that he has been duly appointed as
Attorney-in-Fact by such Selling Shareholder pursuant to a validly existing and
binding Power of Attorney which authorizes such Attorney-in-Fact to take such
action.

                                Very truly yours,

                                Quintiles Transnational Corp.

                                By:  /s/ Rachel R. Selisker
                                     -------------------------------------------
                                     Name: Rachel R. Selisker
                                     Title: Chief Financial Officer,
                                            Executive Vice President Finance and
                                            Treasurer


                                Barrie S. Haigh
                                David F. White
                                Irene White
                                Paul Knott, Ph.D.
                                Kathryn M. Knott
                                Stella D. Haigh
                                Barrie Haigh Children's Settlement No.1
                                Barrie Haigh Children's Settlement No.2
                                David Martin Fleet
                                Victoria S. Fleet
                                Jonathan Kenneth Bolter
                                Sally-Ann Bolter
                                Nicholas John McCooke
                                Susan McCooke
                                Christopher S. Morley
                                Elaine Morley

                                By:  /s/ Rachel R. Selisker
                                     -------------------------------------------
                                     Name: Rachel R. Selisker

                                As Attorney-in-Fact acting on behalf of
                                the above named Selling Shareholders.





                                       11
<PAGE>   12

                                   HSBC Private Equity Investments Limited
                                   Lloyds Development Capital Limited
                                   MSS Nominees Limited (Account 758170)
                                   MSS Nominees Limited (Account 758979)
                                   MSS Nominees Limited (Account 757549)
                                   MSS Nominees Limited (Account 778392)
                                   General Accident Executor and Trustee
                                      Company Limited (Account H715)
                                   General Accident Executor and Trustee
                                      Company Limited (Account H716)

                                   By:  /s/ Christopher M. Masterson
                                        ------------------------------------
                                        Name: Christopher M. Masterson

                                   As Attorney-in-Fact acting on behalf of
                                   the above named Selling Shareholders.


                                   Ludo J. Reynders, Ph.D.
                                   Santo J. Costa
                                   Gregory D. Porter

                                   By:  /s/ Rachel R. Selisker
                                        -----------------------------------
                                        Name: Rachel R. Selisker

                                   As Attorney-in-Fact acting on behalf of
                                   the above named Selling Shareholders.

Accepted as of the date hereof:

Goldman Sachs International
Morgan Stanley & Co. International Limited
Smith Barney Inc.
William Blair & Company, L.L.C.

By: Goldman Sachs International


By:/s/ Elizabeth J. Ford
   ---------------------------
           (Attorney-in-fact)
On behalf of each of the Underwriters





                                       12
<PAGE>   13

                                   SCHEDULE I
<TABLE>
<CAPTION>
                                                                                            NUMBER OF OPTIONAL
                                                                                               SHARES TO BE
                                                                     TOTAL NUMBER OF           PURCHASED IF
                                                                       FIRM SHARES            MAXIMUM OPTION
                           UNDERWRITER                               TO BE PURCHASED            EXERCISED
                           -----------                              ------------------  -------------------------
<S>                                                                  <C>                         <C>
Goldman Sachs International . . . . . . . . . . . . . . . . . . .        288,000                  43,200
Morgan Stanley & Co. International Limited  . . . . . . . . . . .        288,000                  43,200
Smith Barney, Inc.  . . . . . . . . . . . . . . . . . . . . . . .        144,000                  21,600
William Blair & Company, L.L.C.   . . . . . . . . . . . . . . . .        144,000                  21,600
ABN AMRO Rothschild . . . . . . . . . . . . . . . . . . . . . . .         48,000                   7,200
Bayerische Landesbank Girozentrale  . . . . . . . . . . . . . . .         48,000                   7,200
                                                                         -------                 -------

    Total   . . . . . . . . . . . . . . . . . . . . . . . . . . .        960,000                 144,000
                                                                         -------                 -------
</TABLE>





<PAGE>   14


                                 SCHEDULE II
<TABLE>
<CAPTION>
                                                                                        NUMBER OF
                                                                                        OPTIONAL
                                                                                       SHARES TO BE
                                                                TOTAL NUMBER OF          SOLD IF
                                                                  FIRM SHARES         MAXIMUM OPTION
                                                                   TO BE SOLD           EXERCISED
                                                               ------------------  -----------------
<S>                                                                 <C>                      <C>
The Company   . . . . . . . . . . . . . . . . . . . . . . .          283,000                   0

The Selling Shareholders:
   Barrie S. Haigh(a)*  . . . . . . . . . . . . . . . . . .           45,395              24,945
   David F. White(a)  . . . . . . . . . . . . . . . . . . .              100                   0
   Irene White (a)  . . . . . . . . . . . . . . . . . . . .              200                   0
   Paul Knott, Ph.D.(a)   . . . . . . . . . . . . . . . . .            5,017                   0
   Kathryn M. Knott(a)  . . . . . . . . . . . . . . . . . .            4,900                   0
   Stella D. Haigh(a)*  . . . . . . . . . . . . . . . . . .           10,000              10,000
   Barrie Haigh Children's Settlement No. 1(a)*   . . . . .           20,000              10,000
   Barrie Haigh Children's Settlement No. 2(a)*   . . . . .           15,000               5,000
   HSBC Private Equity Investments Limited(b)*  . . . . . .          327,502              61,120
   Lloyds Development Capital Limited(b)  . . . . . . . . .           60,000                   0
   MSS Nominees Limited (Account 758170)(b)*  . . . . . . .           23,675               4,418
   MSS Nominees Limited (Account 758979)(b)*  . . . . . . .           10,576               1,973
   MSS Nominees Limited (Account 757549)(b)*  . . . . . . .           94,714              17,676
   MSS Nominees Limited (Account 778392)(b)*  . . . . . . .            8,047               1,502
   General Accident Executor and Trustee
       Company Limited (Account H715)(b)* . . . . . . . . .           31,571               5,892
   General Accident Executor and Trustee
       Company Limited (Account H716)(b)* . . . . . . . . .            7,896               1,474
   David Martin Fleet(a)  . . . . . . . . . . . . . . . . .            1,890                   0
   Victoria S. Fleet(a)   . . . . . . . . . . . . . . . . .            2,000                   0
   Jonathan Kenneth Bolter(a)   . . . . . . . . . . . . . .              632                   0
   Sally-Ann Bolter(a)  . . . . . . . . . . . . . . . . . .              632                   0
   Nicholas John McCooke(a)   . . . . . . . . . . . . . . .              907                   0
   Susan McCooke(a)   . . . . . . . . . . . . . . . . . . .              798                   0
   Christopher S. Morley(a)   . . . . . . . . . . . . . . .              714                   0
   Elaine Morley(a)   . . . . . . . . . . . . . . . . . . .              714                   0
   Ludo J. Reynders, Ph.D.(c)   . . . . . . . . . . . . . .            3,000                   0
   Santo J. Costa(c)  . . . . . . . . . . . . . . . . . . .            1,000                   0
   Gregory D. Porter(c)   . . . . . . . . . . . . . . . . .              120                   0
                                                                     -------             -------

Total . . . . . . . . . . . . . . . . . . . . . . . . . . .          960,000             144,000
                                                                     -------             -------
</TABLE>

          (a)    This Selling Shareholder is represented by Skadden, Arps,
Slate, Meagher & Flom LLP and has appointed Barrie S. Haigh, Paul Knott, Ph.D.,
Dennis B. Gillings, Ph.D.





<PAGE>   15

and Rachel R. Selisker, and each of them, as the Attorneys-in-Fact for such
Selling Shareholder.

          (b)    This Selling Shareholder is represented by Skadden, Arps,
Slate, Meagher & Flom LLP and has appointed Christopher M. Masterson and Ian M.
Forrest, and each of them, as the Attorneys-in-Fact for such Selling
Shareholder.

          (c)    This Selling Shareholder is represented by Smith, Anderson,
Blount, Dorsett, Mitchell & Jernigan, L.L.P. and has appointed Barrie S. Haigh,
Paul Knott, Ph.D., Dennis B. Gillings, Ph.D. and Rachel R. Selisker, and each
of them, as the Attorneys-in-Fact for such Selling Shareholder.





                                      II-2