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                                                                     EXHIBIT 4.2

                        PAREXEL INTERNATIONAL CORPORATION

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                           SECOND AMENDED AND RESTATED
                                     BY-LAWS

                           Adopted September 13, 2001

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                                    ARTICLE I
                                  Stockholders

         1.       Annual Meeting. The normal meeting of stockholders shall be
held on the second Thursday in November in each year (or if that be a legal
holiday in the place where the meeting is to be held, on the next succeeding
full business day) at 2:00 p.m., unless a different date or hour for such
meeting is fixed by the Directors or the Chief Executive Officer and stated in
the notice of the meeting. The purposes for which the annual meeting is to be
held, in addition to those prescribed by law, by the Articles of Organization or
by these By-laws, may be specified by the Directors or the Chief Executive
Officer.

         2.       Special Meetings. Special meetings of stockholders may be
called by the Chief Executive Officer or by the Directors. Upon written
application of one or more stockholders who hold at least 10% in interest of the
capital stock entitled to vote at a meeting, a special meeting shall be called
by the Clerk, or in the case of the death, absence, incapacity or refusal of the
Clerk, by another officer. Notwithstanding the immediately preceding sentence,
if the corporation has a class of voting stock registered under the Securities
Exchange Act of 1934, as amended, upon written application of one or more
stockholders who hold at least 33-1/3% in interest of the capital stock entitled
to vote at a meeting, a special meeting shall be called by the Clerk, or in case
of the death, absence, incapacity or refusal of the Clerk, by any other officer.

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         3.       Place of Meetings. All meetings of stockholders shall be held
at the principal office of the corporation unless a different place (within or
without Massachusetts, but within the United States) is fixed by the Directors
or the Chief Executive Officer and stated in the notice of the meeting.

         4.       Notice of Meetings. A written notice of the place, date and
hour of all meetings of stockholders stating the purpose of the meeting shall be
given by the Clerk or an Assistant Clerk or by the person calling the meeting at
least twenty days before the meeting or such longer period as is required by law
to each stockholder entitled to vote thereat and to each stockholder who under
the law, under the Articles of Organization or under these By-laws, is entitled
to such notice, by leaving such notice with him or at his residence or usual
place of business, or by mailing it, postage prepaid, and addressed to such
stockholder at his address as it appears in the records of the corporation.
Whenever notice of a meeting is required to be given a stockholder under any
provision of the Massachusetts Business Corporation Law or of the Articles of
Organization or these By-laws, a written waiver thereof, executed before or
after the meeting by such stockholder or his attorney thereunto authorized and
filed with the records of the meeting, shall be deemed equivalent to such
notice.

         5.       Notice of Stockholder Business. The following provisions of
this Section 5 shall apply to the conduct of business at any meeting of the
stockholders. (As used in this Section 5, the term annual meeting shall include
a special meeting in lieu of annual meeting.)

                  (a)      At any meeting of the stockholders, only such
business shall be conducted as shall have been brought before the meeting (i)
pursuant to the corporation's notice of meeting, (ii) by or at the direction of
the Board of Directors or (iii) by any stockholder of the corporation who is a
stockholder of record at the time of giving of the notice provided for in
paragraph (b) of this Section 5, who shall be entitled to vote at such meeting
and who complies with the notice procedures set forth in paragraph (b) of this
Section 5.

                  (b)      For business to be properly brought before any
meeting of the stockholders by a stockholder pursuant to clause (iii) of
paragraph (a) of this By-law, the stockholder must have given timely notice
thereof in writing to the Clerk of the corporation. To be timely, a
stockholder's notice must be delivered to or mailed and received at the
principal executive offices of the corporation (i) in the case of any annual
meeting, not less than sixty days nor more than ninety days prior to the date
specified in Section 1 above for such annual meeting, regardless of

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any postponements, deferrals or adjournments of that meeting to a later date;
provided, however, that if a special meeting in lieu of annual meeting of
stockholders is to be held on a date prior to the date specified in Section 1
above, and if less than seventy days' notice or prior public disclosure of the
date of such special meeting in lieu of annual meeting is given or made, notice
by the stockholder to be timely must be so delivered or received not later than
the close of business on the tenth day following the earlier of the date on
which notice of the date of such special meeting in lieu of annual meeting was
mailed or the day on which public disclosure was made of the date of such
special meeting in lieu of annual meeting; and (ii) in the case of a special
meeting (other than a special meeting in lieu of an annual meeting), not later
than the tenth day following the earlier of the day on which notice of the date
of the scheduled meeting was mailed or the day on which public disclosure was
made of the date of the scheduled meeting. A stockholder's notice to the Clerk
shall set forth as to each matter the stockholder proposes to bring before the
meeting, (i) a brief description of the business desired to be brought before
the meeting and the reasons for conducting such business at the meeting, (ii)
the name and address, as they appear on the corporation's books, of the
stockholder proposing such business, the name and address of the beneficial
owner, if any, on whose behalf the proposal is made, and the name and address of
any other stockholders or beneficial owners known by such stockholder to be
supporting such proposal, (iii) the class and number of shares of the
corporation which are owned beneficially and of record by such stockholder of
record, by the beneficial owner, if any, on whose behalf the proposal is made
and by any other stockholders or beneficial owners known by such stockholder of
record and/or of the beneficial owner, if any, on whose behalf the proposal is
made, in such proposed business and any material interest of any other
stockholders or beneficial owners known by such stockholder to be supporting
such proposal in such proposed business, to the extent known by such
stockholder.

                  (c)      Notwithstanding anything in these By-laws to the
contrary, no business shall be conducted at a meeting except in accordance with
the procedures set forth in this By-law. The person presiding at the meeting
shall, if the facts warrant, determine that business was not properly brought
before the meeting and in accordance with the procedures prescribed by these
By-laws, and if he should so determine, he shall so declare at the meeting and
any such business not properly brought before the meeting shall not be
transacted. Notwithstanding the foregoing provisions of this By-law, a
stockholder shall also comply with all applicable requirements of the

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Securities Exchange Act of 1934, as amended (or any successor provision), and
the rules and regulations thereunder with respect to the matters set forth in
this By-law.

                  (d)      This provision shall not prevent the consideration
and approval or disapproval at the meeting of reports of officers, Directors and
committees of the Board of Directors, but, in connection with such reports, no
new business shall be acted upon at such meeting unless properly brought before
the meeting as herein provided.

         6.       Quorum. The holders of a majority in interest of all stock
issued, outstanding and entitled to vote at a meeting shall constitute a quorum,
but a lesser number may adjourn any meeting from time to time without further
notice; except that, if two or more classes of stock are outstanding and
entitled to vote as separate classes, then in the case of each such class, a
quorum shall consist of the holders of a majority in interest of the stock of
that class issued, outstanding and entitled to vote.

         7.       Voting and Proxies. Each stockholder shall have one vote for
each share of stock entitled to vote owned by him and a proportionate vote for a
fractional share, unless otherwise provided by the Articles of Organization in
the case that the corporation has two or more classes or series of stock.
Capital stock shall not be voted if any installment of the subscription therefor
has been duly demanded in accordance with the law of the Commonwealth of
Massachusetts and is overdue and unpaid. Stockholders may vote either in person
or by written proxy. Proxies shall be filed with the clerk of the meeting, or of
any adjournment thereof, before being voted. No proxy dated more than six months
before the date named therein shall be valid and no proxy shall be valid after
the final adjournment of such meeting. Notwithstanding the provisions of the
preceding sentence, a proxy coupled with an interest sufficient in law to
support an irrevocable power, including, without limitation, an interest in
shares or in the corporation generally, may be made irrevocable if it so
provides, need not specify the meeting to which it relates, and shall be valid
and enforceable until the interest terminates, or for such shorter period as may
be specified in the proxy. Except as otherwise limited therein, proxies shall
entitle the persons named therein to vote at any adjournment of such meeting but
shall not be valid after final adjournment of such meeting. A proxy with respect
to stock held in the name of two or more persons shall be valid if executed by
any one of them unless at or prior to exercise of the proxy the corporation
receives a specific written notice to the contrary from any one of them. A proxy
purporting to be executed

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by or on behalf of a stockholder shall be deemed valid unless challenged at or
prior to its exercise and the burden of proving invalidity shall rest on the
challenger.

         8.       Action at Meeting. When a quorum is present, the holders of a
majority of the stock present or represented and voting on a matter (or if there
are two or more classes of stock entitled to vote as separate classes, then in
the case of each such class, the holders of a majority of the stock of that
class present or represented and voting on a matter), except where a larger vote
is required by law, the Articles of Organization or these By-laws, shall decide
any matter to be voted on by the stockholders. Any election of Directors or
officers by the stockholders shall be determined by a plurality of the votes
cast by stockholders entitled to vote at the election. Any such elections shall
be by ballot if so requested by any stockholder entitled to vote thereon. The
corporation shall not directly or indirectly vote any share of its own stock.

         9.       Action Without Meeting. Any action required or permitted to be
taken at any meeting of the stockholders may be taken without a meeting if all
stockholders entitled to vote on the matter consent to the action in writing and
the written consents are filed with the records of the meetings of stockholders.
Such consent shall be treated for all purposes as a vote at a meeting.

                                   ARTICLE II

                                    Directors

         1.       Powers. The business of the corporation shall be managed by a
Board of Directors who may exercise all the powers of the corporation except as
otherwise provided by law, by the Articles of Organization or by these By-laws.
In the event of vacancy in the Board of Directors, the remaining Directors,
except as otherwise provided by law, may exercise the powers of the full Board
until the vacancy is filled.

         2.       Number, Election and Qualification, Tenure; Removal. The
number of Directors, the provisions governing their election and qualification,
their tenure and removal shall be as provided by law and as set forth in the
Articles of Organization.

         3.       Meetings. Regular meetings of the Directors may be held
without call or notice at such places and at such times as the Directors may
from time to time determine, provided that any Director who is absent when such
determination is made shall be given notice of the

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determination. A regular meeting of the Directors may be held without a call or
notice at the same place as the annual meeting of stockholders.

         Special meetings of the Directors may be held at any time and place
designated in a call by the Chief Executive Officer or two or more Directors.

         4.       Telephone Conference Meetings. Members of the Board of
Directors may participate in a meeting of the board by means of a conference
telephone or similar communications equipment by means of which all persons
participating in the meeting can hear each other at the same time and
participation by such means shall constitute presence in person at a meeting.

         5.       Notice of Meetings. Notice of all special meetings of the
Directors shall be given to each Director by the Secretary, or Assistant
Secretary, or if there be no Secretary or Assistant Secretary, by the Clerk, or
Assistant Clerk, or in case of the death, absence, incapacity or refusal of such
persons, by the officer or one of the Directors calling the meeting. Notice
shall be given to each Director in person or by telephone or by telegram sent to
his business or home address at least twenty-four hours in advance of the
meeting, or by written notice mailed to his business or home address at least
forty-eight hours in advance of the meeting. Notice of a meeting need not be
given to any Director if a written waiver of notice, executed by him before or
after the meeting, is filed with the records of the meeting, or to any Director
who attends the meeting without protesting prior thereto or at its commencement
the lack of notice to him. A notice or waiver of notice of a Directors' meeting
need not specify the purposes of the meeting.

         6.       Quorum. At any meeting of the Directors, a majority of the
Directors then in office shall constitute a quorum. Less than a quorum may
adjourn any meeting from time to time without further notice.

         7.       Action at Meeting. At any meeting of the Directors at which a
quorum is present, a majority of the Directors present may take any action on
behalf of the Board except to the extent that a larger number is required by law
or the Articles of Organization or these By-laws.

         8.       Action by Consent. Any action required or permitted to be
taken at any meeting of the Directors may be taken without a meeting, if all the
Directors consent to the action in writing and the written consents are filed
with the records of the meetings of Directors. Such consents shall be treated
for all purposes as a vote at a meeting.

         9.       Committees. The Directors may, by vote of a majority of the
Directors then in office, elect from their number an executive or other
committees and may by like vote delegate thereto

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some or all of their powers except those which by law, the Articles of
Organization or these By-laws they are prohibited from delegating to such
committee. Except as the Directors may otherwise determine, any such committee
may make rules for the conduct of its business, but unless otherwise provided by
the Directors or in such rules, its business shall be conducted as nearly as may
be in the same manner as is provided by these By-laws for the Directors.

                                   ARTICLE III

                                    Officers

         1.       Enumeration. The officers of the corporation shall consist of
a President, a Treasurer, a Clerk, and such other officers, including without
limitation a Chairman of the Board, a Chief Executive Officer, a Chief Financial
Officer, , one or more Executive Vice Presidents, Senior Vice Presidents, Vice
Presidents, Assistant Treasurers, Assistant Clerks, Secretary and Assistant
Secretaries as may be determined in accordance with these By-laws.

         2.       Election. The Chief Executive Officer, President, Treasurer,
Clerk and Chief Financial Officer shall be elected annually by the Directors at
their first meeting following the annual meeting of stockholders, or at such
other meeting as the Directors shall determine in accordance with these By-laws.
Other officers may be appointed by the Chief Executive Officer, except that the
Directors shall have the power to rescind any such appointment by vote of a
majority of the Directors then in office.

         3.       Qualification. The Chief Executive Officer and/or the
President may, but need not be, a Director. No officer need be a stockholder.
Any two or more offices may be held by the same person, provided that the
President and Clerk shall not be the same person. The Clerk shall be a resident
of Massachusetts unless the corporation has a resident agent appointed for the
purpose of service of process. Any officer may be required by the Directors to
give bond for the faithful performance of his duties to the corporation in such
amount and with such sureties as the Directors may determine.

         4.       Tenure. Except as otherwise provided by law, by the Articles
of Organization or by these By-laws, the Chief Executive Officer, President,
Treasurer and Clerk shall hold office until the first meeting of the Directors
following the next annual meeting of stockholders and until their successors are
chosen and qualified; and all other officers shall hold office until the first

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meeting of the Directors following the next annual meeting of stockholders and
until their successors are chosen and qualified, unless a shorter term is
specified in the vote choosing or appointing them. Any officer may resign by
delivering his written resignation to the corporation at its principal office or
to the Chief Executive Officer, President, Clerk or Secretary, and such
resignation shall be effective upon receipt unless it is specified to be
effective at some other time or upon the happening of some other event.

         5.       Removal. The Directors may remove any officer with or without
cause by vote of a majority of the Directors then in office; provided, that an
officer may be removed for cause only after a reasonable notice and opportunity
to be heard before the Board of Directors.

         6.       Chief Executive Officer, President, Chairman of the Board and
Vice-President . The Chief Executive Officer of the corporation shall, subject
to the direction of the Directors, have general supervision and control of its
business. Unless otherwise provided by the Directors he shall preside, when
present, at all meetings of stockholders and, unless a Chairman of the Board has
been elected and is present, of the Directors.

         If a Chairman of the Board is elected he shall preside at all meetings
of the Board of Directors at which he is present. The Chairman of the Board
shall have such other powers as the Directors may from time to time designate.
Any Vice-President, including any Executive or Senior Vice Presidents, shall
have such powers as the Directors may from time to time designate.

         7.       Chief Financial Officer, Treasurer and Assistant Treasurers.
The Chief Financial Officer shall, subject to the direction of the Directors,
have general charge of the financial affairs of the corporation and shall cause
accurate books of account to be kept. He shall have custody of all funds,
securities, and valuable documents of the corporation, except as the Directors
may otherwise provide.

         The Treasurer and any Assistant Treasurer shall have such powers as the
Directors may from time to time designate.

         8.       Clerk and Assistant Clerks. The Clerk shall record all
proceedings of the stockholders in a book to be kept therefor. Unless a transfer
agent is appointed, the Clerk shall keep or cause to be kept in Massachusetts,
at the principal office of the corporation or at his office, the stock and
transfer records of the corporation, in which are contained the names of all
stockholders and the record address and the amount of stock held by each.

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         In case a Secretary is not elected, the Clerk shall record all
proceedings of the Directors in a book to be kept therefor.

         In the absence of the Clerk from any meeting of the stockholders, an
Assistant Clerk, if one be elected, otherwise a Temporary Clerk designated by
the person presiding at the meeting, shall perform the duties of the Clerk. Any
Assistant Clerk shall have such additional powers as the Directors may from time
to time designate.

         9.       Secretary and Assistant Secretaries. If a Secretary is
elected, he shall keep a record of the meetings of the Directors and in his
absence, an Assistant Secretary, if one be elected, otherwise a Temporary
Secretary designated by the person presiding at the meeting, shall keep a record
of the meetings of the Directors.

         Any Assistant Secretary shall have such additional powers as the
Directors may from time to time designate.

         10.      Other Powers and Duties. Each officer shall, subject to these
By-laws, have in addition to the duties and powers specifically set forth in
these By-laws, such duties and powers as are customarily incident to his office,
and such duties and powers as the Directors may from time to time designate.

                                   ARTICLE IV

                                  Capital Stock

         1.       Certificates of Stock. Subject to the provisions of Section 2
below, each stockholder shall be entitled to a certificate of the capital stock
of the corporation in such form as may be prescribed from time to time by the
Directors. The certificate shall be signed by the Chairman of the Board, the
President or a Vice-President, and by the Treasurer or an Assistant Treasurer;
provided, however, such signatures may be facsimiles if the certificate is
signed by a transfer agent, or by a registrar, other than a Director, officer or
employee of the corporation. In case any officer who has signed or whose
facsimile signature has been placed on such certificate shall have ceased to be
such officer before such certificate is issued, it may be issued by the
corporation with the same effect as if he were such officer at the time of its
issue.

         Every certificate issued for shares of stock at a time when such shares
are subject to any restriction on transfer pursuant to the Articles of
Organization, these By-laws or any agreement

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to which the corporation is a party shall have the restriction noted
conspicuously on the certificate and shall also set forth on the face or back of
the certificate either the full text of the restriction or a statement of the
existence of such restriction and a statement that the corporation will furnish
a copy thereof to the holder of such certificate upon written request and
without charge. Every stock certificate issued by the corporation at a time when
it is authorized to issue more than one class or series of stock shall set forth
upon the face or back of the certificate either the full text of the
preferences, voting powers, qualifications and special and relative rights of
the shares of each class and series, if any, authorized to be issued, as set
forth in the Articles of Organization, or a statement of the existence of such
preferences, powers, qualifications, and rights, and a statement that the
corporation will furnish a copy thereof to the holder of such certificate upon
written request and without charge.

         2.       Stockholder Open Accounts. The corporation may maintain or
caused to be maintained stockholder open accounts in which may be recorded all
stockholders' ownership of stock and all changes therein. Certificates need not
be issued for shares so recorded in a stockholder open account unless requested
by the stockholder.

         3.       Transfers. Subject to the restrictions, if any, stated or
noted on the stock certificates, shares of stock may be transferred in the
records of the corporation by the surrender to the corporation or its transfer
agent of the certificate therefor, properly endorsed or accompanied by a written
assignment and power of attorney properly executed, with necessary transfer
stamps affixed, and with such proof of the authenticity of signature as the
corporation or its transfer agent may reasonably require. When such stock
certificates are thus properly surrendered to the corporation or its transfer
agent, the corporation or transfer agent shall cause the records of the
corporation to reflect the transfer of the shares of stock. Except as may be
otherwise required by law, by the Articles of Organization or by these By-laws,
the corporation shall be entitled to treat the record holder of stock as shown
in its records as the owner of such stock for all purposes, including the
payment of dividends and the right to vote with respect thereof, regardless of
any transfer, pledge or other disposition of such stock, until the shares have
been transferred on the books of the corporation in accordance with the
requirements of these By-laws.

         It shall be the duty of each stockholder to notify the corporation of
his post office address.

         4.       Record Date. The Directors may fix in advance a time which
shall be not more than sixty (60) days before the date of any meeting of
stockholders or the date for the payment of any

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dividend or the making of any distribution to stockholders or the last day on
which the consent or dissent of stockholders may be effectively expressed for
any purpose, as the record date for determining the stockholders having the
right to notice of and to vote at such meeting and any adjournment thereof or
the right to receive such dividend or distribution or the right to give such
consent or dissent. In such case only stockholders of record on such record date
shall have such right, notwithstanding any transfer of stock on the books of the
corporation after the record date. Without fixing such record date the Directors
may for any of such purposes close the transfer books for all or any part of
such period.

         If no record date is fixed and the transfer books are not closed, the
record date for determining stockholders having the right to notice of or to
vote at a meeting of stockholders shall be at the close of business on the day
next preceding the day on which notice is given, and the record date for
determining stockholders for any other purpose shall be at the close of business
on the day on which the Board of Directors acts with respect thereto.

         5.       Replacement of Certificates. In case of the alleged loss,
mutilation or destruction of a certificate of stock, a duplicate certificate may
be issued in place thereof, upon such terms and conditions as the Directors may
prescribe.

         6.       Issue of Capital Stock. The whole or any part of the then
authorized but unissued shares of each class of stock may be issued at any time
or from time to time by the Board of Directors without action by the
stockholders.

         7.       Reacquisition of Stock. Shares of stock previously issued
which have been reacquired by the corporation, may be restored to the status of
authorized but unissued shares by vote of the Board of Directors, without
amendment of the Articles of Organization.

                                    ARTICLE V

                             Provisions to Directors
                      Officers, Stockholders and Employees

         1.       Certain Contracts and Transactions. In the absence of fraud or
bad faith, no contract or transaction by this corporation shall be void,
voidable or in any way affected by reason of the fact that the contract or
transaction is (a) with one or more of its officers, Directors, stockholders or
employees, (b) with a person who is in any way interested in this corporation or
(c) with a

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corporation, organization or other concern in which an officer, Director,
stockholder or employee of this corporation is an officer, Director, stockholder
or employee of such corporation or in any way interested. The provisions of this
section shall apply notwithstanding the fact that the presence of a Director or
stockholder, with whom a contract or transaction is made or entered into or who
is an officer, director, stockholder or employee of a corporation, organization
or other concern with which a contract or transaction is made or entered into or
who is in any way interested in such contract or transaction, was necessary to
constitute a quorum at the meeting of the Directors (or any authorized committee
thereof) or stockholders at which such contract or transaction was authorized
and/or that the vote of such Director or stockholder was necessary for the
adoption of such contract or transaction, provided that if said interest was
material, it shall have been known or disclosed to the Directors or stockholders
voting at said meeting on said contract or transaction. A general notice to any
person voting on said contract or transaction that an officer, Director,
stockholder or employee has a material interest in any corporation, organization
or other concern shall be sufficient disclosure as to such officer, Director,
stockholder or employee with respect to all contracts and transactions with such
corporation, organization or other concern. This section shall be subject to
amendment or repeal only by action of the stockholders.

         2.       Indemnification. Each Director and officer of the corporation,
and any person who, at the request of the corporation, serves as a director or
officer of another organization shall be indemnified by the corporation against
any cost, expense (including attorneys' fees), judgment, liability and/or amount
paid in settlement reasonably incurred by or imposed upon him in connection with
any action, suit or proceeding (including any proceeding before any
administrative or legislative body or agency), to which he may be made a party
or otherwise involved or with which he shall be threatened, by reason of his
being, or related to his status as, a Director or officer of the corporation or
of any other organization, which other organization he serves or has served as
director or officer at the request of the corporation (whether or not he
continues to be an officer or Director of the corporation or such other
organization at the time such action, suit or proceeding is brought or
threatened), unless such indemnification is prohibited by the Business
Corporation Law of the Commonwealth of Massachusetts. The foregoing right of
indemnification shall be in addition to any rights to which any such person may
otherwise be entitled and shall inure to the benefit of the executors or
administrators of each

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such person. The corporation may pay the expenses incurred by any such person in
defending a civil or criminal action, suit or proceeding in advance of the final
disposition of such action, suit, or proceeding, upon receipt of an undertaking
by such person to repay such payment if it is determined that such person is not
entitled to indemnification hereunder. This section shall not affect any rights
to indemnification to which corporate personnel other than Directors and
officers may be entitled by contract or otherwise under law. This section shall
be subject to amendment or repeal only by action of the stockholders, and any
such amendment or repeal shall not affect the rights arising hereunder prior to
the effective date of the amendment or repeal.

                                   ARTICLE VI

                            Miscellaneous Provisions

         1.       Fiscal Year. Except as from time to time otherwise determined
by the Directors, the fiscal year of the corporation shall be the twelve (12)
months ending the last day of June. Following any change in the fiscal year
previously adopted, a certificate of such change, signed under the penalties of
perjury by the Clerk or an Assistant Clerk, shall be filed forthwith with the
state secretary.

         2.       Seal. The seal of this corporation shall, subject to
alteration by the Directors, bear its name, the word "Massachusetts", and the
year of its incorporation.

         3.       Execution of Instruments. All deeds, leases, transfers,
contracts, bonds, notes and other obligations authorized to be executed by an
officer of the corporation in its behalf shall be signed by the Chief Executive
Officer, the President, any Vice President or the Chief Financial Officer or
Treasurer except as the Directors may generally or in particular cases otherwise
determine.

         4.       Voting of Securities. Except as the Directors may otherwise
designate, the Chief Executive Officer or Chief Financial Officer may waive
notice of, and appoint any person or persons to act as proxy or attorney in fact
for this corporation (with or without power of substitution) at any meeting of
stockholders or shareholders of any other corporation or organization, the
securities of which may be held by the corporation.

         5.       Corporate Records. The original, or attested copies, of the
Articles of Organization, By-laws and records of all meetings of incorporators
and stockholders, and the stock and transfer

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records, which shall contain the names of all stockholders and the record
address and the amount of stock held by each, shall be kept in Massachusetts at
the principal office of the corporation or at an office of its transfer agent or
of the Clerk or of its resident agent. Said copies and records need not all be
kept in the same office. They shall be available at all reasonable times to the
inspection of any stockholder for any proper purpose but not to secure a list of
stockholders or other information for the purpose of selling said list or
information or copies thereof or of using the same for a purpose other than in
the interest of the applicant, as a stockholder, relative to the affairs of the
corporation.

         6.       Articles of Organization. All references in these By-laws to
the Articles of Organization shall be deemed to refer to the Restated Articles
of Organization of the corporation, as amended and in effect from time to time.

         7.       Amendments. These By-laws, to the extent provided in these
By-laws, may be amended or repealed, in whole or in part, and new By-laws
adopted either (a) by the stockholders at any meeting of the stockholders by the
affirmative vote of the holders of at least a majority in interest of the
capital stock present and entitled to vote, provided that notice of the proposed
amendment or repeal or of the proposed making of new By-laws shall have been
given in the notice of such meeting, or (b) if so authorized by the Restated
Articles of Organization, by the Board of Directors at any meeting of the Board
by the affirmative vote of a majority of the Directors then in office, but no
amendment or repeal of a By-law shall be voted by the Board of Directors and no
new By-laws shall be made by the Board of Directors which alters the provisions
of these By-laws with respect to removal of Directors, or the election of
committees by Directors and the delegation of powers thereto, nor shall the
Board of Directors make, amend or repeal any provision of the By-laws which by
law, the Restated Articles of Organization or the By-laws requires action by the
stockholders. Not later than the time of giving notice of the meeting of
stockholders next following the making, amending, or repealing by the Directors
of any By-law, notice thereof stating the substance of such change shall be
given to all stockholders entitled to vote on amending the By-laws. Any By-law
or amendment of a By-law made by the Board of Directors may be amended or
repealed by the stockholders by affirmative vote as above provided in this
Section 7.

<PAGE>

                                      -15-

         8.       1987 Massachusetts Control Share Acquisition Act. The 1987
Massachusetts Control Share Acquisition Act, Chapter 110D of the Massachusetts
General Laws, as it may be amended from time to time, shall not apply to the
corporation.

<PAGE>

                                AMENDMENT No. 1

                                     to the

                       SECOND AMENDED AND RESTATED BY-LAWS

                                       of

                        PAREXEL INTERNATIONAL CORPORATION

                                 March 27, 2003

         The Board of Directors of PAREXEL International Corporation (the
"Corporation") on March 27, 2003, approved an amendment to the Second Amended
and Restated By-laws of the Corporation, as follows:

         That Section 2 of Article I of the Second Amended and Restated Bylaws
         of the Corporation be and hereby is deleted in its entirety and the
         following Section 2 is inserted in lieu thereof:

                  "2. Special Meetings. Special meetings of stockholders may be
         called by the Chief Executive Officer or by the Board of Directors. In
         addition, upon written application of one or more stockholders who are
         entitled to vote and who hold at least the Required Percentage (as
         defined below) of the capital stock entitled to vote at the meeting,
         special meetings shall be called by the Clerk, or in case of the death,
         absence, incapacity or refusal of the Clerk, by any other officer.

                  For purposes of this Section 2, the "Required Percentage"
         shall be (i) 10% at any time at which the corporation shall not have a
         class of voting stock registered under the Securities Exchange Act of
         1934, as amended (the "Exchange Act"), and (ii) 80% or such lesser
         percentage as shall constitute the maximum percentage permitted by law
         for this purpose at any time at which the corporation shall have a
         class of voting stock registered under the Exchange Act."