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                                                                  EXHIBIT 10.1.G


                        AMENDMENT TO EMPLOYMENT AGREEMENT

         This AMENDMENT TO EMPLOYMENT AGREEMENT (the "Amendment") amends that
certain EMPLOYMENT AGREEMENT by and between CLINTRIALS RESEARCH INC., a Delaware
corporation ("Company"), and S. COLIN NEILL ("Executive") dated as of October
22, 1998 (the "Employment Agreement") and is entered into between Company and
Executive this ____ day of _____________, 2000.

         WHEREAS, the parties wish to amend the Employment Agreement as set
forth below;

         IT IS, ACCORDINGLY, AGREED AS FOLLOWS:

         1. The last sentence of Section 2(c) of the Employment Agreement is
amended to read as follows:

                  Further, any stock options granted to the Executive will be
                  fully vested upon a Change of Control, whether or not the
                  Executive is terminated, notwithstanding any previously stated
                  vesting restrictions, and will remain exercisable for the
                  remainder of the stated term of such stock option(s),
                  regardless of whether the Executive continues to be employed
                  by the Company.

         2. The following is added after the last sentence of Section 2(c) of
the Employment Agreement:

                  For purposes of this Agreement, "Change of Control" shall mean
                  (i) the acquisition of beneficial ownership (within the
                  meaning of Rule 13d-3 promulgated under the Securities and
                  Exchange Act of 1934, as amended (the "Exchange Act")) of
                  greater than 50% of the then outstanding voting securities of
                  the Company entitled to vote generally in the election of
                  directors (the "Voting Securities") by any individual, entity
                  or group (within the meaning of Section 13(d)(3) of the
                  Exchange Act and the rules and regulations thereunder), other
                  than by the Company, an employee benefit plan (or related
                  trust) sponsored or maintained by the Company; (ii) a sale of
                  all or substantially all of the assets of the Company; (iii) a
                  sale or other transfer of assets of the Company, in one or a
                  series of transactions, representing more than 50% of the
                  total fair market value of the Company's assets immediately
                  prior to the transaction (or the first transaction, if there
                  are a series of transactions); (iv) any merger,




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                  consolidation, reorganization, recapitalization or other
                  corporate transaction with respect to the Company, unless the
                  holders of the Voting Securities immediately prior to such
                  transaction own more than 50% of the voting securities of the
                  entity resulting from such transaction or the entity which
                  controls such resulting entity (in substantially the same
                  percentages as they held prior to such transaction); or (v)
                  the date, following the expiration of any period of twelve
                  consecutive months that individuals, who at the beginning of
                  such period constituted the Board (together with any new
                  directors whose election by such Board or whose nomination for
                  election by the shareholders of the Company was approved by a
                  vote of a majority of the directors of the Company then still
                  in office who were either directors at the beginning of such
                  period or whose election or nomination for election was
                  previously so approved) cease for any reason to constitute a
                  majority of the Board then in office.

         3. The first paragraph of Section 5(c) of the Employment Agreement is
amended to read as follows:

                           (c) Termination Without "Cause" or for "Good Reason"
                  (as such term is defined below). If the Company should
                  terminate the Executive's employment for any reason (including
                  a termination as a result of a Change of Control) other than
                  for Cause, or in the event the Executive terminates employment
                  for Good Reason or Company gives notice of its intent not to
                  renew this Agreement under Section 1(b), the Company shall pay
                  the Executive, in a lump sum within ten (10) days following
                  his termination of employment, an amount equal to the
                  Executive's then current monthly Base Salary times eighteen
                  (18). The Executive shall also be entitled to:

         4. The portion of Section 5(c)(ii) of the Employment Agreement labeled
"(1)" is amended to read as follows:

                  (1) the end of the 18-month period following his termination
                  of employment; and





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         5. The second Section 5(c) of the Employment Agreement ("Termination
Without Good Reason") is renumbered as Section 5(d).

         6. The following is added as Section 5(e) of the Employment Agreement:

                           (e) If the Executive resigns from employment for any
                  reason, other than Retirement or Disability, during the 90-day
                  period following a Change of Control, such resignation shall
                  be deemed to be a termination by the Executive for Good Reason
                  for purposes of Section 5(c).

                                    In the event of the termination of
                  employment of the Executive by the Company without Cause or by
                  the Executive for Good Reason or resignation following a
                  Change of Control, if the Executive is required, pursuant to
                  Section 4999 of the Internal Revenue Code of 1986, as amended
                  (the "Code"), to pay (through withholding or otherwise) an
                  excise tax on "excess parachute payments" (as defined in
                  Section 280G of the Code), the Company shall pay the Executive
                  the amount necessary to place the Executive in the same
                  after-tax financial position that he would have been in if he
                  had not incurred any excise tax liability under Section 4999
                  of the Code.

         7. The following is added as Section 5(f) of the Employment Agreement:

                           (f) Termination shall be deemed to be a result of a
                  Change of Control (i) if such termination occurs within twelve
                  (12) months following the Change of Control; or (ii) if any
                  change in the Executive's title, reporting relationship,
                  responsibilities or authority as in effect immediately prior
                  to any Change of Control is made within twelve (12) months of
                  such Change of Control and which adversely affects to a
                  material degree his role in the management of the Company; or
                  (iii) if any reduction in the Executive's salary paid to him
                  by the Company 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; or (iv) if any termination of the Executive's employee
                  benefit programs, including, but not limited to, any stock
                  option plan, investment plan, savings plan, incentive
                  compensation plan or life insurance, medical plans or
                  disability plans provided by the Company to the Executive and
                  in which the Executive is participating or under which the
                  Executive is covered, all as in effect immediately prior to
                  any Change of Control; or (v) if there is any requirement by
                  the Company that the





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                  Executive's position and principal office be based and located
                  more than twenty (20) miles outside the boundaries of the
                  principal office of the Executive immediately prior to the
                  Change of Control; or (vi) if any failure or refusal of the
                  Company to renew this Employment Agreement under Section 1(b)
                  after any Change of Control shall have occurred.

         8. In all other respects the Employment Agreement is hereby ratified
and affirmed.


                                       CLINTRIALS RESEARCH INC.



                                       By:
                                           -------------------------------------
                                       Title:
                                             -----------------------------------


                                       EXECUTIVE



                                       -----------------------------------------
                                       S. COLIN NEILL





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