EXHIBIT 10.33
                                                                 -------------


                              EMPLOYMENT AGREEMENT
                              --------------------


         THIS AGREEMENT, effective the 1st day of October, 1998, by and between
BioReliance Corporation and all of its subsidiary companies and its successors
or assigns (the "Corporation") and Michael R.N. Thomas (the "Employee").

                             Preliminary Statements
                             ----------------------

         WHEREAS, the Employee is currently employed by the Corporation;

         WHEREAS, the parties desire to provide for the continued employment of
the Employee by the Corporation on the terms and conditions set forth in this
Agreement; and

                        Terms and Conditions of Agreement
                        ---------------------------------

         NOW THEREFORE, in consideration of the mutual promises and agreements
set forth in this Agreement, the adequacy of which are acknowledged, and with
the intent to be bound hereby, the Corporation and Employee agree as follows:

         A.       POSITION

                  The Employee will be employed as Chief Financial Officer of
         the Corporation through November 15, 1998. Thereafter, the Corporation,
         at its election, may continue Employee in the position of Chief
         Financial Officer through the remainder of the Term (as hereinafter
         defined), or the Corporation many elect to change Employee's position
         to Vice President, Corporate Development. Employee shall continue as
         Vice President, Corporate Development, or such other senior management
         position as may be determined by the Corporation from time to time,
         through the remainder of the Term.

         B.       DUTIES

                  As Chief Financial Officer, Employee shall perform such duties
         as may be assigned to him from time to time (consistent with the
         limitations set forth in Section D(iv) of this Agreement) by the
         President and Chief Executive Officer ("CEO"), including, but not
         limited to: (i) finance, accounting and treasury responsibilities; (ii)
         diligently pursuing the filing of the Corporation's 10-Q for the third
         quarter and signing the same; (iii) handling the investor conference
         call and other contacts specifically related to the release of the
         Corporation's third quarter 1998 results; and (iv) maintaining a policy
         that contacts with investors, analysts, investment brokers or managers
         and other like persons will be at the direction of the President and
         CEO of the Corporation, except for routine contacts with bank and cash
         managers.


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                  As Vice President, Corporate Development, Employee shall
         perform such duties as may be assigned to him from time to time by the
         President and CEO of the Corporation, including, but not limited to,
         the evaluation and analysis of acquisition opportunities related to
         such target companies as may be identified from time to time by the
         President and CEO. The Corporation and Employee acknowledge that the
         duties of Vice President, Corporate Development may not require the
         full-time attention of the Employee, and the Corporation shall be
         flexible concerning the Employee's hours and place of work for the
         remainder of the Term.

                  Employee shall continue to be entitled to all rights of
         indemnification by the Corporation as to which he is presently
         entitled, and the Corporation's obligation to indemnify Employee shall
         not be diminished by the limitations on Employee's duties or hours of
         work.

         C.       TERM

                  The terms and conditions of this Employment Agreement will
         cover a period beginning as of the date hereof and ending on December
         31, 1998 (the "Term"), unless otherwise terminated as provided in
         Section E below. During the Term of this Agreement, the parties
         acknowledge that Employee's employment is not "at will" employment, and
         the Corporation's obligation to pay Employee the compensation described
         in Section D of this Agreement shall exist regardless of any decision
         by the Corporation to terminate Employee's employment for any reason
         (other than a termination for cause) prior to the expiration of the
         Term. At the end of the Term of this Agreement, the Employee's
         employment status shall terminate. The terms and conditions contained
         in Section E of this Agreement will expire at the end of the Term.

         D.       COMPENSATION AND BENEFITS

                  (i)      Base Salary

                           The Employee's annual base salary will be One Hundred
                  and Seventy-Five Thousand Dollars ($175,000), payable on the
                  Corporation's regular bi-weekly payroll basis. The Employee
                  shall receive only that portion of the base which will become
                  due during the Term, and not the total annual base salary.

                  (ii)     Bonus

                           The Employees shall be paid a bonus of Fifteen
                  thousand Dollars ($15,000), less applicable withholdings and
                  deductions (if any), on January 1, 1999.


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                  (iii)    Incentive Compensation

                           As an inducement to remain in the employ of the
                  Corporation and as an incentive to build the Corporation's
                  value, if the Employee remains in the employ of the
                  Corporation through December 31, 1998, and performs his duties
                  as described in Paragraph B hereof (consistent with the
                  limitations set forth in Section D(iv) of this Agreement), he
                  shall be paid a bonus in the amount of $35,000 (less
                  applicable withholdings and deductions, if any), without
                  appraisal, at such time as other bonuses are paid in the first
                  quarter of 1999. The Corporation will be obligated to pay
                  Employee this Incentive Compensation bonus no later than
                  January 15, 1999 as long as Employee (i) does not resign from
                  the Corporation before December 31, 1998 and (ii) is not
                  terminated for Cause (as hereinafter defined) on or before
                  December 31, 1998.

                  (iv)     Hours of Work

                           From the date hereof until November 15, 1998, the
                  Employee shall be required to work no more than thirty (30)
                  hours per week performing his duties as CFO and all hours in
                  excess thereof will be governed by Section G hereof. After
                  November 15, 1998, all hours in excess of sixteen (16) hours
                  per week spent by Employee performing his duties will be
                  governed by Section G hereof.

                  (v)      Other Provisions

                           The Corporation will provide such medical and other
                  coverage to the Employee as the Corporation makes available to
                  all employees generally from time to time. The Employee will
                  also receive the Corporation's standard vacation, sick time
                  and personal holiday benefits. Eligibility to extend group
                  health coverage beyond the Term for Employee or any dependants
                  may be exercised by signing the applicable COBRA agreement.
                  Employee will continue accruing Paid Personal Leave (PPL)
                  through the Term.

         E.       TERMINATION COMPENSATION AND BENEFITS

                  In the event that during the Term of this Agreement, the
         Employee's employment with the Corporation is involuntarily terminated
         by the Corporation other than for Cause or because of the Employee's
         death or substantial inability to work, the Corporation will pay the
         Employee a lump sum payment equal to all amounts that would have
         otherwise become due hereunder, including without limitation the Bonus
         and Incentive Compensation described in Section D (ii) and (iii)
         hereof.

                  For a period of twelve (12) months after such termination, the
         Corporation will also continue to make available the same health and
         dental (but no other) benefits made available to Corporation employees
         generally at a cost equal to the


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         cost the Employee would have paid if he had continued to be an employee
         of the Corporation. In the event the Employee becomes employed at any
         time during the twelve (12) month continuance period, all remaining
         health and dental benefits shall terminate as of date of hire by the
         Employee's new employer.

                  If Employee terminates his employment prior to the end of the
         Term, the Corporation shall have no further obligations under Sections
         D or E hereof after the effective date of termination.

                  As used in this Agreement, "Cause" shall mean that the
         Employee (a) committed a material act or material acts of personal
         dishonesty intended to result in the Employee's personal enrichment at
         the expense of the Corporation, and which constitute(s) fraud, grand
         larceny or any felonious act, (b) failed or refused to perform the
         Employee's material duties and obligations (consistent with the
         limitations set forth in Section D(iv) of this Agreement) as an
         employee, officer and/or director of the Corporation (other than due to
         disability or reasons beyond the Executive's reasonable control) if
         such failure or approval is not remedied within a reasonable period of
         time following the Employee's receipt of notice thereof.

         F.       CONFIDENTIALITY

                  By signing below, Employee acknowledges his ongoing and
         continuing obligation to abide by the Confidentiality, Trade Secrets
         and Noncompetition Agreement that he executed on July 28, 1998, and to
         keep secret or confidential, and not to utilize in any matter or
         disclose to third parties, any proprietary and confidential information
         of the Corporation, which may have been made available to him or came
         into his possession during the period of his employment with
         Corporation. Employee also agrees that, during and after the Term, he
         shall not make any defamatory or disparaging comments about the
         Corporation, its agents, employees, successors, assigns, corporate
         parent, affiliates, officers, or directors to third parties, or to
         former, present, or prospective customers, clients, vendors, business
         associates or anyone else in the industry, and shall not unlawfully
         interfere with the business advantage or contracts of the Corporation,
         its successors, assigns, corporate subsidiaries, and affiliates. During
         and after the Term, the Corporation agrees that it shall not make any
         defamatory or disparaging comments about Employee.

         G.       CONSULTING SERVICES

                  During the Term, the Employee and Corporation may also agree
         that Employee will provide separate and additional consulting services
         in excess of the hours of performance required pursuant to Section D
         hereof, and during the 3 1/2 month period following the expiration of
         the Term hereof, as set forth in Exhibit A, Employee may provide such
         consulting services to the Corporation for the purpose of accomplishing
         a smooth transition of obligations from Employee to the new Chief
         financial Officer and to facilitate the Corporation's quarterly and
         year-end audits and the filing of its subsequent annual report on Form
         10-K, tax


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         filings and matters related thereto. Such services shall be provided on
         the terms and conditions set forth in the Professional Services
         Agreement attached hereto as Exhibit A.The CEO must approve all
         consulting services to be provided by Employee in writing in advance of
         the performance of such services.

         H.       SURVIVAL

                  Except for the terms and conditions set forth above in Section
         E, the terms and conditions of this Agreement, including without
         limitation the terms and conditions set forth above in Section F
         regarding Confidentiality, Non-Competition and Non-Solicitation, will
         remain in effect after the end of the Term.

         I.       ASSIGNABILITY

                  Except by will or by the laws of descent and distribution,
         neither this Agreement nor any right or interest hereunder shall be
         assignable or transferable by the Employee or by the Employee's
         beneficiaries or legal representatives. This Agreement shall inure to
         the benefit of and be enforceable by the Employee's legal personal
         representative.

         J.       GOVERNING LAW

                  This agreement shall be construed and governed by the laws of
         the State of Maryland without regard to its choice of law provisions.

         K.       SEVERABILITY

         The provisions of this Agreement shall be deemed severable, and the
         invalidity or unenforceability of any provision shall not affect the
         validity or enforceability of the other provisions hereof.

         L.       ENTIRE AGREEMENT

                  This Agreement constitutes the entire Agreement between the
         Corporation and the Employee and supersedes all prior agreements,
         offers, terms or conditions regarding Employee's employment, except for
         the Confidentiality, Trade Secrets and Noncompetition Agreement, which
         will survive.

         M.       WAIVER

                  Employee acknowledges, absent this Agreement, Employee has no
         right or entitlement to any severance payment and benefit, or to a
         separate allowance in any particular amount. For the consideration set
         forth in Section D (ii) hereof, the adequacy of which is hereby
         acknowledged, except for breach of this Agreement by the Corporation,
         the Employee hereby remises, releases and forever discharges and
         quitclaims onto the Corporation and its officers, directors,
         shareholders, employees, agents and representatives of and from any and
         all debts, actions, causes of action, suits, accounts, covenants,
         contracts, agreements, damages, and


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         any and all claims, demands and liabilities whatsoever of every name
         and nature, both in Law and in Equity (collectively referred to therein
         as "Claims"), which the Employee now has or ever had from the beginning
         of time.

         N.       NO CONFLICTS OF INTEREST

                 By signing this Agreement, the Employee represents that he is
         not subject to any restrictions, particularly, but without limitation,
         in connection with any previous employment, which prevents the Employee
         from entering into and performing his obligations under this Agreement
         or which materially and adversely affect (or may in the future, so far
         as the Employee can reasonably foresee, materially and adversely
         affect), the Employee's right to participate in the affairs of the
         Corporation.

         O.       PROOF OF CITIZENSHIP AND ABILITY TO WORK

                  This Agreement is contingent on the Employee providing the
         Corporation, if not previously provided, with proof of U.S. citizenship
         or alien work permission, as required by federal law.



                                       BioReliance Corporation


                                       By: ___________________________
                                           Name:  Capers W. McDonald
                                           Title: President and CEO


                                       _______________________________
                                       Michael R.N. Thomas


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                                                                     EXHIBIT A

                         PROFESSIONAL SERVICES AGREEMENT
                                     BETWEEN
                             BIORELIANCE CORPORATION
                                       AND
                               MICHAEL R.N. THOMAS


         THIS AGREEMENT is entered into as of date below written by and between
BioReliance Corporation ("BioReliance"), a Delaware Corporation, with principal
offices located at 9900 Blackwell Rd, Rockville, Maryland 20850, and Michael
R.N. Thomas ("Consultant") residing at 12566 Lime Kiln Road, Fulton, MD 20759.

                                   WITNESSETH

         WHEREAS, BioReliance desires to have Consultant perform professional
services to assist BioReliance in facilitating the transition of the duties of
Chief Financial Officer, and

         WHEREAS, Consultant has served as the Chief Financial Officer for
BioReliance and its subsidiaries and affiliates (the "Corporation")

         NOW, THEREFORE, in consideration of the mutual covenants and agreements
contained herein, BioReliance and Consultant agree as follows:

1.       SCOPE OF WORK

         Subject to the terms and conditions hereinafter provided, Consultant
may provide professional services related to transition of the duties of Chief
Financial Officer and the filing of certain reports with the Securities and
Exchange Commission and the Internal Revenue Service in connection with the
close of the Corporation's fiscal year. Services shall include, but not be
limited to the following: reasonable assistance upon prior notice at reasonable
times and locations as may be mutually agreed by BioReliance and Consultant in
connection with the close of the Corporation's books for year end 1998; the
filing of the Corporation's 10-K, annual report and proxy materials for 1998;
the filing of the Company's various tax retentions; and the audit of the
Corporation's books for 1998.

2.       TERM AND TERMINATION

         This Agreement shall have a term commencing on October 1, 1998, or such
an earlier or later date as the parties agree, and terminating April 15, 1999.

3.       CONSIDERATION AND PAYMENT TERMS

         As consideration for services provided by Consultant, BioReliance shall
pay the consultant the hourly rate of $200 per hour.


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4.       DIRECTION

         Consultant shall report to and receive direction from Capers W.
McDonald, President and Chief Executive Officer ("CEO"), or other individuals
designated by BioReliance from time to time. All services to be provided under
this Agreement require the prior written approval of the CEO. The Corporation
will not be obligated to pay any fees pursuant to this Agreement for services
which have not been approved in writing by the CEO prior to the performance of
such services.

5.       TRAVEL

         BioReliance agrees to reimburse Consultant for any non-local travel and
living expenses incurred in the performance of this Agreement if such non-local
travel is approved in advance by the CEO. Reimbursement will be in accordance
with BioReliance's travel policy.

6.       PROPRIETARY INFORMATION

         In providing services to BioReliance, Consultant may have knowledge of
its affairs, trade secrets, potential customers and other proprietary
information. Consultant shall treat all such information as proprietary and
confidential to BioReliance in accordance with the Confidentiality Agreements
dated July 8, 1998 and July 28, 1998 between BioReliance and Consultant.

7.       WARRANTY

         Consultant warrants that the professional services provided under this
Agreement will be performed competently and in accordance with the standard of
care usually and reasonably expected in performance of such services.

8.       INDEPENDENT PARTIES

         Nothing in this Agreement shall be construed as to create any
relationship between BioReliance and Consultant other than that of independent
contracting parties. Neither party shall have any right, power or authority to
assume, create or incur any expense, liability or obligation, express or
implied, on behalf of the other.

9.       WAIVER

         No waiver by either party of any breach of any provision hereof shall
constitute a waiver of any other breech of that or any other provision hereof.


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10.      SEVERABILITY

         If any part, term or provision of this Agreement is determined to be
invalid or unenforceable, the remainder of this Agreement shall not be affected,
and this Agreement shall otherwise remain in full force and effect.

11.      ARBITRATION

         Any claim or controversy relating to or rising out of the Agreement
shall be resolved exclusively by arbitration, in accordance with the rules then
obtaining of the American Arbitration Association.

12.      ENTIRE AGREEMENT

         This Agreement sets forth the entire agreement and understanding
between BioReliance and Consultant relating to the Services to be performed
hereunder. This Agreement supersedes all other communications between
BioReliance and Consultant relating to the subject matter hereof.

         Any amendments to or modifications of this Agreement shall be effective
only if reduced to writing and executed by both BioReliance and Consultant.

13.      HEADINGS

         The Subject matter headings used in this Agreement are solely for
convenience and are not to be taken as modifying, clarifying, describing or
limiting any provisions hereof.

         IN WITNESS THEREOF, BioReliance and Consultant have caused this
Agreement to be executed by their duly authorized representative as of the dates
set forth above.

             BioReliance Corporation


         By    __________________                By    ___________________

         Name  Capers W. McDonald                Name  Michael R.N. Thomas
               __________________                      ___________________

         Title President and CEO
               __________________                      ___________________

         Date  October 1, 1998                   Date  October 1, 1998
               __________________                      ___________________