Exhibit 10.10




                                  Covance Inc.



                              Amended and Restated

                     Supplemental Executive Retirement Plan
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                                  Covance Inc.

                              AMENDED AND RESTATED
                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN


                                    ARTICLE I
                                  INTRODUCTION

In recognition of the services provided to Covance Inc. by certain of its key
executives, the Board of Directors of Covance Inc. establishes this Supplemental
Executive Retirement Plan (the "Plan") for the purpose of providing supplemental
retirement income for each selected individual. The Plan is to be maintained and
operated according to the terms of this document. The Compensation and
Organization Committee of the Board of Directors of Covance Inc. shall have the
sole authority to manage and administer this Plan.

                                   ARTICLE II
                                   DEFINITIONS

As used herein, the following words and phrases shall have the meanings
described below: 
        2.1 Accrued Benefit shall mean the amount of pension benefit payable
as a single life annuity as shall be considered earned at any time for a
Participant in accordance with the provisions of Article IV. Such pension
benefit shall be payable in the form chosen by the Participant pursuant to
Article VII.
        2.2 Actuarial Equivalent shall mean a lump sum benefit of equivalent
value based on the applicable mortality rates, set back one year, and 120% of
the applicable interest rate, both as published by the Pension Benefit Guaranty

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Corporation for purposes of determining the present value of a lump sum
distribution on plan termination. Such lump sum benefit shall be determined as
of the first day of the year prior to the Participant's date of retirement or
other termination of employment occurs. Application of such assumptions to the
computation of benefits payable under the Plan shall be made uniformly and
consistently with all respect to the Plan.
        2.3 Board shall mean the Board of Directors of Covance Inc.
        2.4 Change In Control shall mean:
            (i) any person (including as such term is used in Section 13(d)
        and 14(d)(2) of the Securities Exchange Act of 1934) becomes the
        beneficial owner, directly or indirectly, of Covance's securities
        representing 20% or more of the combined voting power of Covance's
        then outstanding securities; or
            (ii) as a result of a proxy contest or contests or other forms of
        contested shareholder votes (in each case either individually or in
        the aggregate), a majority of the individuals elected to serve on
        Covance's Board of Directors are different then the individuals who
        served on Covance's Board of Directors at any time within the two
        years prior to such proxy contest or contests or other forms of
        contested shareholder votes (in each case either individually or in
        the aggregate); or
            (iii) Covance shareholders approve a merger, or consolidation
        (where in each case Covance is not the survivor thereof), or sale or
        disposition of all or substantially all of Covance's assets or a plan
        of partial or complete liquidation; or
            (iv) an offerer (other than Covance Inc.) purchases shares of the
        Covance's common stock pursuant to a tender or exchange offer for such
        shares.
        2.5 Code shall mean the Internal Revenue Code of 1986, as amended from
time to time.
        2.6 Committee shall mean the Compensation and Organization Committee of
the Board of Directors.
        2.7 Constructive Termination shall mean:

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            (i) a material breach by Covance of this Agreement, including,
        without limitation, a reduction in your then current salary or the
        percentage of base salary eligible for incentive compensation;

            (ii) a diminution of your responsibilities, status, title or
        duties hereunder;

            (iii) a relocation of your work place which increases the
        distance between your principal residence and your work place by more
        than 25 miles;

            (iv) a failure by Covance to provide you with benefits which are
        as favorable to you in all material respects as those provided
        immediately prior to the Change of Control; or

            (v) the failure of any acquiror or successor in interest to the
        business of Covance to agree in writing to be bound by the terms of this
        Agreement within four months of any Change of Control.

        2.8 Covance Inc. shall mean Covance Inc., a Delaware Corporation and any
successor thereto.
        2.9 Disability shall mean a disability qualifying for benefits payable
under the Covance Inc. long-term disability plan under which the Participant is
covered.
        2.10 Final Average Earnings shall mean the average of the sum of the
Participant's monthly Plan Compensation during the sixty (60) consecutive
calendar months (or the total number of months if less than sixty) within the
one hundred twenty (120) months (or the total number of months if less than 120)
immediately preceding the Participant's termination of employment with Covance
Inc., in which his Plan Compensation was the highest. In the case of a disabled
Participant, who is receiving disability benefits under any long term disability
insurance provided by Covance Inc., his Final Average Earnings shall be computed
based on his Plan Compensation immediately prior to becoming disabled.
        2.11 Participant shall mean an individual who has been designated as a
Participant in this Plan under Section 3.1. In the event of the death or

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incompetency of a Participant, the term shall mean his personal representative
or guardian.
        2.12 Plan shall mean the Covance Inc. Supplemental Executive Retirement
Plan set forth in this document and as amended by Covance Inc. from time to
time.
        2.13 Plan Compensation shall mean the base salary paid to a Participant
by Covance Inc. (including salary reductions which are deferred under Section
401(k) or 125 of the Code), plus annual bonuses.
        2.14 Plan Year shall mean the calendar year.
        2.15 Year of Service shall mean each full 12 consecutive months of
employment completed by a Participant as an employee of Covance Inc., or its
subsidiaries. In addition, the Years of Service of a Participant employed by
Covance Inc. on January 1, 1997 shall include all periods of service completed
with Corning Incorporated or its affiliates.

                                   ARTICLE III
                                  PARTICIPATION

        3.1 Eligibility to Participate. Any individual designated by the
Committee shall be eligible to participate in this Plan. The Committee may
delegate the authority to designate eligible employees to the Chief Executive
Officer. Plan Participants shall be limited to a select group of management and
highly compensated employees of Covance Inc. and its subsidiaries.
        3.2 Commencement of Participation. Each individual who has satisfied the
requirements of Section 3.1 shall commence participation in the Plan upon
designation by the Committee as a Participant in the Plan.

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                                   ARTICLE IV
                           AMOUNT OF PENSION BENEFITS

        4.1 Normal Retirement Benefits. A Participant who retires on or after
the completion of 20 Years of Service shall have an Accrued Benefit equal to 40%
of his Final Average Earnings payable on the attainment of age 60.
Notwithstanding the foregoing, a Participant employed with Covance Inc. on
January 1, 1997 who completes 15 Years of Service shall have an Accrued Benefit
equal to 40% of his Final Average Earnings payable on the attainment of age 60.
        A Participant who retires or terminates employment prior to the
completion of 20 Years of Service shall have his Accrued Benefit reduced by
multiplying the Accrued Benefit by a fraction, the numerator of which is the
Participant's actual Years of Service and the denominator of which is 20.
Notwithstanding the preceding sentence, a Participant employed by Covance Inc.
on January 1, 1997 who retires or terminates employment prior to completion of
15 Years of Service shall have his Accrued Benefit reduced by multiplying the
Accrued Benefit by a fraction, the numerator of which is the Participant's
actual Years of Service and the denominator of which is 15.
        A Participant who becomes Disabled shall be immediately eligible to
receive a benefit under the Plan.
        A Participant's benefits determined under this Section shall be adjusted
in accordance with Section 4.2 or Section 4.3 if his Accrued Benefit becomes
payable at other than his attainment of age 60.
        4.2 Early Retirement. A Participant who has been credited with five
Years of Service and has attained age 55 may, with Committee approval, elect to
retire before becoming eligible for normal retirement benefits. A Participant
who elects to retire and commence benefit payments prior to the attainment of
age 60, shall be subject to a reduction in his Accrued Benefit of 5% of the
amount of Accrued Benefit for each year payment of benefits occurs prior to the
Participant's attainment of age 60.

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        4.3 Late Retirement. A Participant who elects to retire and commence
benefit payments after age 60 will be entitled to an increase in his Accrued
Benefit of 5% of the amount of Accrued Benefit for each year benefit payments
are delayed beyond age 60. A Participant's Accrued Benefit will not be increased
for benefit payments that commence after age 65.
        4.4 Service Crediting. Years of Service for purposes of determining the
amount of a Participant's Accrued Benefit and vesting shall be determined in
accordance with Section 2.14 of this Plan. In addition, a Participant may be
granted, at the discretion of the Committee, credit for years of service with a
previous employer for the purposes of determining his Accrued Benefit and
vesting. The Committee shall credit such service in writing at the time of the
Participant's commencement of participation in this Plan and shall have the
authority to require a reduction or offset of the Participant's Accrued Benefit
under this Plan by the amount of any retirement benefit provided to the
Participant under the plan or plans of the previous employer for which prior
service credit is given.

                                    ARTICLE V
                                     VESTING

        5.1 Vesting of Benefits. A Participant shall become 100% vested in his
Accrued Benefit upon being credited with five Years of Service. In addition, a
Participant shall become 100% vested upon his Disability or death while still
employed by Covance Inc. or its subsidiaries.

                                   ARTICLE VI
                            DEATH PRIOR TO RETIREMENT

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        6.1 Pre-Retirement Death Benefits for Married Participants. In the event
of the death of a married Participant whose death occurs while still in the
employ of Covance Inc. or its subsidiaries and after the completion of five
Years of Service, his surviving spouse shall be entitled to receive an amount in
the form of a lump sum payment which shall be fifty percent (50%) of the
Actuarial Equivalent of the Accrued Benefit the Participant would have been
eligible to receive under Section 4.1 adjusted in accordance with Sections 4.2
or 4.3, if applicable, had he retired on the day before his death. Such payment
will commence as of the date the Participant would have attained age 55, or if
later, as soon as administratively feasible after the Participant's death.
        6.2 Pre-Retirement Death Benefit for Participants with Surviving
Children. In the event of the death of a Participant, who is survived by one or
more children, while the Participant is still in the employ of Covance Inc. or
its subsidiaries and after the completion of five Years of Service, his
surviving children shall be entitled to receive an amount in the form of a lump
sum payment which shall be fifty percent (50%) of the Actuarial Equivalent of
the Accrued Benefit the Participant would have been eligible to receive under
Section 4.1 adjusted in accordance with Sections 4.2 or 4.3, if applicable, had
he retired on the day before his death. The benefit described in the preceding
sentence shall be divided equally among the Participant's surviving children.
Such payment will occur as of the date the Participant would have attained age
55, or if later, as soon as administratively feasible after the Participant's
death.
        6.3 No Other Pre-Retirement Death Benefits. Except as provided in
Sections 6.1 and 6.2, no other death benefits shall be payable under this Plan
in the event of the death of a Participant prior to retirement or termination of
employment.

                                   ARTICLE VII

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                               PAYMENT OF BENEFITS

        7.1 Retirement. A Participant shall, upon his retirement, in accordance
with Article IV, be entitled to receive his Accrued Benefit in the form of one
of the following: a single life annuity payable monthly, quarterly or on an
annual basis; a lump sum equal to the Actuarial Equivalent of the Accrued
Benefit, calculated in accordance with Section 2.2; or a joint and 50% or 100%
survivor annuity actuarially reduced to reflect the joint life expectancies of
the Participant and his spouse.
        7.2 Termination of Employment. A Participant who chooses to voluntarily
terminate his employment with Covance Inc. and it subsidiaries prior to the
completion of 5 Years of Service shall forfeit any Accrued Benefit.
        7.3 Facility of Payment. Whenever, in the Committee's opinion, an
individual entitled to receive any payment of a benefit hereunder is under a
legal disability or is incapacitated in any way so as to be unable to manage his
financial affairs, Covance Inc. may make payments to the legal representative of
such person or to a relative or friend of such individual for his benefit or
apply the payment for the benefit of such individual as the Committee deems
advisable.
        7.4 Change In Control. In the event of a Change in Control of Covance
Inc.:
        (a) Each  Participant  in this Plan as of the date of the Change in
Control who is involuntarily terminated or experiences a Constructive
Termination during the three-year period following the Change in Control shall
be credited with three additional Years of Service and three additional years of
age for Accrued Benefit and vesting determination purposes; provided, however,
that such additional credit for these Participants shall be reduced by the
period of service and increase in age the Participant has completed and
experienced between the Change in Control and actual termination of employment.
        (b) In the event this Plan is terminated at any time, each Participant
shall be credited with three additional Years of Service and three additional

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years of age for Accrued Benefits and vesting determination purposes; provided,
however, that this Section 7.4(b) shall not apply to any Participant who has
received additional Years of Service and Years of Age pursuant to Section 7.4(a)
above.

        (c) (i) Anything in this Plan to the contrary notwithstanding, in the
event it shall be determined that any payment or distribution by, to or for the
benefit of the Participant subsequent to a Change in Control (a "Payment"),
would be subject to the excise tax imposed by Section 4999 of the Internal
Revenue Code of 1986, as amended (the "Excise Tax"), then the Participant shall
be entitled to receive an additional payment (a "Gross-Up Payment") in an amount
such that after payment by such Participant of all taxes (including any Excise
Tax) imposed upon the Gross-Up Payment, the Participant retains an amount of the
Gross-Up Payment equal to the Excise Tax imposed upon the Payments.
            (ii) All determinations as to whether a Gross-Up Payment is
required and the amount of such Gross-Up Payment, shall be made by the
accounting firm utilized by Covance Inc. for the preparation of its annual
external financial statements (the "Accounting Firm") which shall provide
detailed supporting calculations both to Covance Inc. and the Participant within
30 days of termination of the Participants's employment, if applicable, or such
earlier time as is requested by Covance Inc. The Gross-Up Payment, if any, as
determined pursuant to this Paragraph (b), shall be paid to Participant within
10 days of the receipt of the Accounting Firm's determination. Any determination
by the Accounting Firm shall be binding upon Covance Inc. and the Participant.
If subsequent final determinations of the Excise Tax made by the Internal
Revenue Service give rise to additional Excise Tax, then additional Gross-Up
Payments shall be made by Covance Inc. to the Participant within 10 days after
the notice is received by Covance Inc. of such final determination.
            (iii) Participants shall notify Covance Inc. in writing of any
claim by the Internal Revenue Service that, if successful, would require the
payment by Covance Inc. of a Gross-Up Payment. Such notification shall be given
as soon as practicable but no later than 10 business days after a Participant
learns

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of such claim. Participant shall not pay such claim prior to the expiration of
the thirty-day period following the date on which Participant gives such notice
to Covance Inc. (or such shorter period ending on the date that any payment of
taxes with respect to such claim is due). If Covance Inc. notifies a Participant
in writing prior to the expiration of such period that it desires to contest
such claim, Participant shall:

                      (A) give Covance Inc. any information reasonably
        requested by Covance Inc. relating to such claim,

                      (B) take such action in connection with contesting such
        claims as Covance Inc. shall reasonably request in writing from time to
        time, including, without limitation, accepting legal representation with
        respect to such claim by an attorney selected by Covance Inc.,

                      (C) cooperate with Covance Inc. in good faith in order to
        effectively contest such claim, and

                      (D) permit Covance Inc. to participate in any proceedings
        relating to such claim;

provided, however, that Covance Inc. shall bear all costs and expenses incurred
in connection with such contest and shall indemnify and hold the Participant
harmless, on an after-tax basis, for any Excise Tax or income tax imposed as a
result of such contest or representation and payment of costs and expenses.
Covance Inc. shall control all proceedings taken in connection with such
contest. Covance Inc. may, at its sole option, either direct the Participant to
pay the tax claimed and sue for a refund or contest the claim in any permissible
manner, and the Participant shall prosecute such contest to a determination
before any administrative tribunal, in a court of initial jurisdiction and in
one or more appellate courts, as Covance Inc. shall determine; provided,
however, that if Covance Inc. directs a Participant to pay such claim and sue
for a refund, Covance Inc. shall advance the amount of such payment to such
Participant on an interest-free basis and shall indemnify and hold such

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Participant harmless, on an after-tax basis, from any Excise Tax or income tax
imposed with respect to such advance.

        (d) If, after the receipt by a Participant of an amount advanced by
Covance Inc. pursuant to Section 7.4(b)(iii), such Participant shall become
entitled to receive any refund with respect to such claim, such Participant
shall promptly pay to Covance Inc. the amount of such refund (together with any
interest paid or credited thereon after taxes applicable thereto). If, after the
receipt by a Participant of an amount advanced by Covance Inc. pursuant to
Section 7.4(b)(iii), a final determination is made that such Participant shall
not be entitled to any refund with respect to such claim, then such advance
shall be forgiven and shall not be required to be repaid and the amount of such
advance shall offset the amount of Gross-Up Payment required to be paid.

                                  ARTICLE VIII
                           AMENDMENTS AND TERMINATION

        8.1 Amendments Generally. The Committee reserves the right to make any
amendment or amendments to this Plan from time to time which do not cause any
reduction in a Participant's Accrued Benefit at the time the amendment is
adopted or the effective date of the amendment, whichever is earlier. Any
amendment shall be made pursuant to a duly adopted resolution of the Committee.

        8.2 Right to Terminate. The Committee may terminate the Plan at any time
in whole or in part. Termination of the Plan shall be made pursuant to a duly
adopted resolution of the Committee. In the event of termination, the Committee
may, at its option, pay each Participant the present value of his Accrued
Benefit at the time of termination of the Plan and make such payments in an
Actuarially Equivalent lump sum. In addition, the Committee may, at its option,
refrain from making payments to any Participant until such time and in such
manner as he would have been entitled to receive his Accrued Benefit

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under the terms of the Plan as in effect on the date of termination.
Notwithstanding the foregoing, if the Plan terminates within three years of a
Change in Control, each Participant will be paid the Actuarial Equivalent of his
Accrued Benefit immediately. No termination of the Plan shall reduce a
Participant's Accrued Benefit as of the date of termination.

        8.3 Funding Obligation. The obligation of Covance Inc. to pay any
benefits under this Plan shall be unfunded and unsecured; any payments under
this Plan shall be made from the general assets of Covance Inc.; provided,
however, in the event of a Change in Control Covance Inc. shall purchase an
annuity from a nationally recognized, credit worthy financial institution of
good reputation for the benefit of the plan in an amount sufficient to fund all
present and reasonably anticipated future obligations under the Plan.
Notwithstanding the foregoing, the Board, in its discretion, may authorize the
establishment of a rabbi trust or any other funding vehicle it deems appropriate
in order to set aside assets to discharge its obligations under this Plan.

                                   ARTICLE IX
                        ADMINISTRATION AND INTERPRETATION

        9.1 Interpretation. The Committee may take any action, correct any
defect, supply any omission or reconcile any inconsistency in the Supplemental
Executive Retirement Plan, or in any election hereunder, in the manner and to
the extent it shall deem necessary to carry the Plan into effect or to carry out
the Board's purposes in adopting the Plan. Any decision, interpretation or other
action made or taken in good faith by or at the direction of Covance Inc., the
Board, or the Committee, arising out of or in connection with the Plan, shall be
within the absolute discretion of all and each of them, as the case may be, and
shall be final, binding and conclusive on Covance Inc., and all Participants and
their respective heirs, executors, administrators, successors and assigns. The
Committee's determinations hereunder need not be uniform, and may be made
selectively among Participants, whether or not they are similarly situated. Any
actions to be taken by the Committee will require the consent of a majority

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of the Committee members. If a member of the Committee is a Participant in this
Plan, such member may not decide or determine any matter or question concerning
his benefits under this Plan that such member would not have the right to decide
or determine if he were not a member.

        9.2 Payment of Expenses. Covance Inc., and its subsidiaries, in such
proportions as the Committee determines, shall bear all expenses incurred by
them and by the Committee in administering this Plan. If a claim or dispute
arises concerning the rights of a Participant or Beneficiary to amounts payable
under this Plan, regardless of the party by whom such claim or dispute is
initiated, Covance Inc. shall pay all legal expenses, including reasonable
attorneys' fees, court costs, and ordinary and necessary out-of-pocket costs of
attorneys, billed to and payable by the Participant or by anyone claiming under
or through the Participant (such person being hereinafter referred to as the
"Participant's Claimant"), in connection with the bringing, prosecuting,
defending, litigating, negotiating, or settling of such claim or dispute;
provided, that:
        (a) The Participant or the Participant's Claimant obtains a judgment in
its favor from a court of competent jurisdiction from which no appeal may be
taken, whether because the time to do so has expired or otherwise; and provided
further, that
        (b) In the case of any claim or dispute initiated by a Participant or
the Participant's Claimant, such claim shall be made, or notice of such dispute
given, with specific reference to the provisions of this Plan, to the Committee
within two years (three years, in the event of a Change in Control) after the
occurrence of the event giving rise to such claim or dispute.
        9.3 Indemnification for Liability. Covance Inc. shall indemnify the
members of the Committee, against any and all claims, losses, damages, expenses
and liabilities arising from their responsibilities in connection with this
Plan, unless the same is determined to be due to gross negligence or willful
misconduct.

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        9.4 Claims Procedure. If a claim for benefits or for participation under
this Plan is denied in whole or in part, a Participant will receive written
notification. The notification will include specific reasons for the denial,
specific reference to pertinent provisions of this Plan, a description of any
additional material or information necessary to process the claim and why such
material or information is necessary, and an explanation of the claims review
procedure. If the Committee fails to respond within 90 days, the claim is
treated as denied.
        9.5 Review Procedure. Within 60 days after the claim is denied or, if
the claim is deemed denied, within 150 days after the claim is filed, a
Participant (or his duly authorized representative) must file a written request
with the Committee for a review of his denied claim or the denial shall be
considered final and no appeal may be taken. The Participant may review
pertinent documents that were used in processing his claim, submit pertinent
documents, and address issues and comments in writing to the Committee. The
Committee will notify the Participant of its final decision in writing. In its
response, the Committee will explain the reason for the decision, with specific
references to pertinent Plan provisions on which the decision was based. If the
Committee fails to respond to the request for review within 60 days, the review
is treated as denied.

                                    ARTICLE X
                            MISCELLANEOUS PROVISIONS

        10.1 Right of Covance Inc. to Take Employment Actions. The adoption and
maintenance of this Plan shall not be deemed to constitute a contract between
Covance Inc. and any eligible Participant, nor to be a consideration for, nor an
inducement or condition of, the employment of any person. Nothing herein
contained, or any action taken hereunder, shall be deemed to give any eligible
Participant the right to be retained in the employ of Covance Inc. or to
interfere with the right of Covance Inc. to discharge any eligible Participant
at any time, nor shall it be deemed to give to an Employer the right to require
the eligible Participant to remain in its employ, nor shall it interfere with
the eligible

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Participant's right to terminate his or her employment at any time. Nothing in
this Plan shall prevent Covance Inc. from amending, modifying, or terminating
any other Covance Inc. benefit plan.
        10.2 Alienation or Assignment of Benefits. A Participant's rights and
interest under the Plan shall not be assigned or transferred except as otherwise
provided herein, and the Participant's rights to benefit payments under the Plan
shall not be subject to alienation, pledge or garnishment by or on behalf of
creditors (including heirs, beneficiaries, or dependents) of the Participant or
of a Beneficiary. Notwithstanding the preceding, the Committee may direct
distributions to an alternate payee pursuant to a Qualified Domestic Relations
Order (QDRO), as defined in Section 414(p) of the Code prior to any distribution
date described in Article IV.
        10.3 Applicable Law. This Plan shall be construed and enforced in
accordance with the laws of Delaware except to the extent superseded by the
Employee Retirement Income Security Act of 1974, as amended.
        10.4 Number and Gender. Whenever any words used herein are in the
singular form, they shall be construed as though they were also used in the
plural form in all cases where they would so apply, and references to the male
gender shall be construed as applicable to the female gender where applicable,
and vice versa.
        10.5 Accelerated Distributions. In the event Federal income is
accelerated on the value of future prospective benefits due to a determination
by the Internal Revenue Service, the Participant may at his election receive an
immediate distribution of the amount necessary to pay the tax obligation due
currently. The Participant's Accrued Benefit under the Plan will be reduced to
reflect the accelerated distribution.

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        To record the adoption of the Plan, Covance Inc. has caused its
authorized officers to affix its corporate name and seal effective November 10,
1998.


[CORPORATE SEAL]                              COVANCE INC.


Attest: _________________________             By: ________________________

                                           Title:_________________________

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