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                                                                   EXHIBIT 10.24

                                  COVANCE INC.
                    2000 EMPLOYEE EQUITY PARTICIPATION PLAN

1.  PURPOSE

    The Covance Inc. 2000 Employee Equity Participation Plan (the "Plan") is
intended to (i) encourage executive, managerial, technical and other Employees
of Covance Inc. (the "Corporation") or a Subsidiary (as defined below) to become
owners of stock of the Corporation in order to increase their proprietary
interest in the Corporation's success; (ii) to stimulate the efforts of certain
key executive, managerial, technical and other Employees by giving suitable
recognition to services which contribute materially to the Corporation's
success; and (iii) to provide such Employees with additional incentive and
reward opportunity.

2.  EFFECTIVE DATE AND DURATION OF PLAN

    The Plan shall become effective upon its approval by the stockholders of the
Corporation. Unless previously terminated by the Corporation's Board of
Directors (the "Board"), the Plan shall have a term of ten years.

3.  DEFINITIONS

    (a) "1934 Act" means the Securities and Exchange Act of 1934, as amended,
including the rules and regulations promulgated thereunder.

    (b) "Award" means a stock option, SAR (as defined below), stock award (as
defined below), any other award made pursuant to the terms of the Plan, or any
combination of them, as described in and granted under the Plan.

    (c) "Award Agreement" is defined in Section 13 hereof.

    (d) "Change of Control" is defined in Section 12(b).

    (e) "Code" means the Internal Revenue Code of 1986, as amended, including
any rules and regulations promulgated thereunder or any successor body of laws,
rules and regulations.

    (f) "Committee" means the Compensation and Organization Committee of the
Board of Directors or such other committee as is appointed by the Board to
administer the Plan.

    (g) "Employee" means an employee or a consultant of the Corporation or a
Subsidiary.

    (h) "Fair Market Value" means the average of the highest and the lowest
quoted selling prices of the Shares on the New York Stock Exchange Composite
Tape on the valuation date, or, if there were no sales on the valuation date,
the average of the highest and lowest quoted selling prices on the New York
Stock Exchange Composite Tape on the first trading day before and the first
trading day after the valuation date.

    (i) "Grant Price" is defined in Section 9 hereof.

    (j) "ISO" means an incentive stock option as defined in Section 422 of the
Code.

    (k) "Non-Statutory Option" means an option that is not an ISO.

    (l) "Participant" means an Employee who has been granted an Award under the
Plan.

    (m) "Prior Plan" means the Covance Inc. Employee Equity Participation
Program.

    (n) "SAR" means a stock appreciation right.

    (o) "Shares" means the common stock of the Corporation, par value $0.01 per
share.

    (p) "Stock Award" means an award other than a stock option or SAR.

    (q) "Subsidiary" means an entity that is directly or indirectly controlled
by the Corporation or any entity, including an acquired entity, in which the
Corporation has a significant equity interest, as determined by the Committee.

    (r) "Treasury Shares" means authorized and issued, but not outstanding,
Shares.
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4.  PLAN ADMINISTRATION

    (a) The Committee shall be responsible for administering the Plan. If
considered appropriate by the Board in light of applicable laws, rules, or
regulations, the Committee shall be comprised of two or more non-employee
members of the Board each of whom is a "Non-Employee Director" within the
meaning of Rule 16b-3 under the 1934 Act and an "outside director" within the
meaning of Section 162(m) of the Code.

    (b) The Committee shall have full and exclusive power to interpret the Plan
and to adopt such rules, regulations, and guidelines for carrying out the Plan
as it may deem necessary or proper, all of which power shall be executed in the
best interests of the Corporation and in keeping with the provisions and
objectives of the Plan. This power includes, but is not limited to
(i) selecting Award recipients and the extent of their participation;
(ii) establishing all Award terms and conditions; (iii) adopting procedures and
regulations governing Awards; and (iv) making all other determinations necessary
or advisable for the administration of the Plan. All decisions made by the
Committee shall be final, binding and conclusive on all persons interested in
the Plan or any Awards.

    The Committee may delegate from time to time during the term of the Plan to
one or more executive officers or directors of the Corporation the authority to
carry out some or all of its responsibilities provided that the Committee may
not delegate its authority and powers in any way which would be inconsistent
with the requirements of the Code or the 1934 Act. The Committee may at any time
rescind the authority delegated to any such executive officer or director.

    To the extent consistent with the Corporation's Amended and Restated
Certificate of Incorporation, no member of the Committee shall be liable for any
action or determination with respect to the Plan, and the members shall be
entitled to indemnification and reimbursement in the manner provided in the
Corporation's Restated Certificate of Incorporation, as amended, modified or
supplemented from time to time. In the performance of its functions under the
Plan, the Committee shall be entitled to rely upon information and advice
furnished by the Corporation's officers, accountants, counsel and any other
party the Committee deems necessary, and no member of the Committee shall be
liable for any action taken or not taken in reliance upon any such advice.

    (c) The Committee may, from time to time, alter or amend, and the Board of
Directors may terminate, the Plan as it shall deem advisable, subject to any
requirement for shareholder approval imposed by applicable law or securities
exchange listing requirements. However, the Committee and Board may not, without
the approval of the Corporation's shareholders, amend the Plan to increase the
number of Shares that may be issued under the Plan (except for adjustments
pursuant to Section 6 hereof), or reduce the minimum Grant Price per share
specified by Section 9(a) hereof.

    (d) The termination of the Plan, either pursuant to Section 2, Section 4(c)
or otherwise, shall not cause any previously granted Awards to terminate. After
the termination of the Plan, any previously granted Awards shall remain in
effect and shall continue to be governed by the terms of the Plan, the Awards,
and any applicable Award Agreements.

5.  PARTICIPATION

    The individuals who shall be eligible to receive Awards under the Plan shall
be Employees (including officers who are directors) as the Committee or one or
more executive officers or directors, in accordance with Section 4(b) hereof
shall approve from time to time.

6.  LIMITATION ON NUMBER OF SHARES

    (a) Subject to the provisions of this Section 6 and Section 7 hereof, up to
3,600,000 Shares may be issued under the Plan. The stock subject to the
provisions of this Plan shall be shares of authorized but unissued Shares and
Treasury Shares.

    (b) In addition to the Shares authorized by Section 6(a) hereof, the
following Shares may be issued under the Plan: (i) Shares that were available
for issuance under the Prior Plan but were not issued or subject to options
granted under the Prior Plan, (ii) Shares that are forfeited under the Prior
Plan and Shares that are not issued under the Prior Plan because of the
cancellation, termination or expiration of awards, and/or other similar events
under the Prior Plan, (iii) Shares that a Participant tenders, or has withheld,
in payment of all or part of the Grant Price under a stock option granted under
the Plan or the Prior Plan, or in satisfaction of tax withholding obligations
hereunder or thereunder, and (iv) Shares that are issued under the Plan which
are subsequently forfeited in accordance with the terms of the Award or an Award
Agreement or shares that are not issued because of the cancellation,
termination, or expiration of Awards and/or similar events under the Plan.
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    (c) Subject to the adjustment provisions set forth herein, not more than
500,000 Shares shall be issued under Awards other than stock options and SARs.

    (d) Subject to the foregoing provisions of this Section 6, if an Award may
be paid only in Shares or in either cash or Shares, the Shares shall be deemed
to be issued hereunder only when and to the extent that payment is actually made
in Shares. However, the Committee may, in its discretion, authorize a cash
payment under an Award in lieu of Shares.

    (e) Subject to the adjustment provisions set forth herein, an individual
Participant may not receive Awards with respect to more than 10% of the number
of Shares specified in Section 6(a) hereof over the term of the Plan.

7.  ADJUSTMENT PROVISIONS

    In the event that any dividend or other distribution (whether in the form of
Shares, other securities, or other property), extraordinary cash dividend,
recapitalization, stock split, reverse stock split, reorganization, merger,
consolidation, split-up, spin-off, combination, repurchase, or exchange of
Shares or other securities, the exercisability of stock purchase rights received
under the Corporation's Rights Agreement with Harris Trust and Savings Bank
dated December 31, 1996, the issuance of warrants or other rights to purchase
Shares or other securities, or other similar corporate transaction or event
materially affects the Shares with respect to which Awards have been or may be
issued under the Plan, then the Committee shall, in a manner and to the extent
that the Committee deems appropriate to prevent any dilution or enlargement of
the benefits or potential benefits intended to be made available under the Plan,
adjust any or all of:

    (a) the number and type of securities that thereafter may be issued under
the Plan,

    (b) the number and type of securities subject to outstanding Awards, and

    (c) the Grant Price or purchase price with respect to any Award, or, if
deemed appropriate, make provision for a cash payment to the holder of an
outstanding Award.

    However, no adjustment shall be authorized with respect to incentive stock
options to the extent that the adjustment would cause the options to violate
Section 422(b) of the Code or any successor provision. In addition, the number
of securities subject to any Award denominated in Shares shall always be a whole
number.

    In the event the Corporation acquires another entity by means of a merger,
consolidation, acquisition of property or stock, reorganization or otherwise,
the Committee shall be authorized to cause the Corporation to issue or to assume
stock options or stock appreciation rights, whether or not in a transaction to
which Section 424(a) of the Code applies, by means of substitution of new
options or rights for previously issued options or rights or an assumption of
previously issued options or rights.

    Subject to any required action by the Corporation's shareholders, if the
Corporation is a party to any merger or consolidation where the Corporation is
not the survivor, a Participant holding an outstanding Award valued directly or
indirectly by Shares shall be entitled to receive, upon the exercise of the
Award, the same per Share consideration (cash, shares or other consideration) on
the same terms that a holder of the same number of Shares that are subject to
the Participant's Award would be entitled to receive pursuant to the merger or
consolidation.

8.  TERMINATION OF GRANTS UNDER THE PRIOR PLAN

    Effective upon the approval of this Plan by the Corporation's shareholders,
no further grants of options, rights, units or other awards are or will be
permitted under the Prior Plan. All grants and awards under the Prior Plan that
remain outstanding after the approval of this Plan by the Corporation's
shareholders shall be administered and paid in accordance with the provisions of
the Prior Plan; PROVIDED, HOWEVER, that the shares related to such grants and
awards which have not been issued prior to this Plan's approval by the
Corporation's shareholders shall be issuable under this Plan in accordance with
Section 9(e) hereof.

9.  AWARDS UNDER THE PLAN

    The following types of Awards may be granted under this Plan, singly, or in
combination as the Committee may determine from time to time:

    (a) Stock Options--A stock option shall represent a right to purchase a
specified number of Shares at a stated exercise price (the "Grant Price") during
a specified time, not to exceed ten years from the date of grant, as determined
by the Committee. The Grant Price per Share for each stock option shall not be
less than 100% of the Fair Market Value on the date of grant. A stock option may
be in the form of an ISO or a Non-Statutory Option which in
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each case is consistent with the applicable terms, conditions, and limitations
established by the Committee. Upon satisfaction of the applicable conditions to
exercisability specified in the terms and conditions of the Award Agreement, the
Participant shall be entitled to exercise the option in whole or in part and to
receive, upon satisfaction or payment of the Grant Price in the manner
contemplated in this Section 9(a), the number of Shares in respect of which the
option shall have been exercised.

    The Shares covered by a stock option may be purchased by methods permitted
by the Committee, including: (i) a cash payment; (ii) tendering Shares owned for
at least six months by the Participant, valued at the Fair Market Value at the
date of exercise; (iii) authorizing the Corporation to sell the Shares (or a
sufficient portion thereof) acquired upon exercise of a stock option, and
assigning to the Corporation a sufficient amount of the sale proceeds to pay for
all the Shares acquired through such exercise and any tax withholding
obligations resulting from such exercise, or (iv) any combination of the above.

    The Committee may not grant additional stock options under the Plan to a
Participant contingent upon the surrender of Shares owned by the Participant in
payment of the Grant Price of a stock option granted under the Plan.

    (b) SARs--An SAR shall represent a right to receive a payment in cash,
Shares, or a combination thereof as determined by the Committee, equal to the
excess of the Fair Market Value of a specified number of Shares on the date the
SAR is exercised over an amount which shall be no less than the Fair Market
Value on the date the SAR was granted as set forth in the applicable Award
Agreement.

    (c) Other Stock Awards--A Stock Award shall represent an Award made in
Shares or denominated in units equivalent in value to Shares or any other Award
based on or related to Shares. All or part of any Stock Award may be subject to
conditions and restrictions established by the Committee, and set forth in the
applicable Award Agreement, which may include, but are not limited to,
continuous service with the Corporation or a Subsidiary and/or the achievement
of Corporation or individual performance goals. The performance criteria that
shall be used by the Committee in granting Stock Awards contingent on
performance goals for officers to which 162(m) of the Code is applicable shall
consist of stock price, earnings level, and return on equity or such other
criteria that shall satisfy the requirements of Section 162(m) or any successor
provision.

    (d) Dividends--The Committee may provide that Awards under Section 9(c) of
the Plan earn dividends or dividend equivalents. Such dividends or dividend
equivalents may be paid currently or may be credited to a participant's account.
Any crediting of dividends or dividend equivalents may be subject to such
restrictions and conditions as the Committee may establish, including
reinvestment in additional Shares or Share equivalents.

    (e) Prior Plan Awards--Awards which, pursuant to their terms, would have
been made under the Prior Plan but were not done so prior to the approval of
this Plan by the Corporation's shareholders, such as "reload" options and
additional performance shares earned under restricted stock agreements, shall be
issued under the Plan in accordance with the terms of the Prior Plan.

10. PAYMENTS AND PAYMENT DEFERRALS

    Payment of Awards may be in the form of cash, Shares, other Awards, or
combinations thereof as the Committee shall determine, and with such
restrictions as it may impose. The Committee also may require or permit
participants to elect to defer the receipt or issuance of Shares from stock
options or Stock Awards or the settlement of Awards in cash under such rules and
procedures as it may establish under the Plan. It also may provide that deferred
settlements of Awards include the payment or crediting of earnings on deferred
amounts, or the payment or crediting of dividend equivalents where the deferred
amounts are denominated in Share equivalents. In addition, the Committee may
stipulate in an Award Agreement, either at the time of grant or by subsequent
amendment to such Award Agreement, that a payment or portion of a payment of an
Award be delayed in the event that Section 162(m) of the Code (or any successor
or similar provision of the Code affecting tax deductibility) would disallow a
tax deduction by the Corporation for all or a portion of such payment. The
period of any such delay in payment shall be until the payment, or portion
thereof, is tax deductible, or such earlier date as the Committee shall
determine.

11. TRANSFERABILITY

    During the lifetime of a Participant, the Award shall be exercisable only by
such Participant and Awards shall not be transferable or assignable other than
by will or the laws of descent and distribution, or pursuant to qualified
domestic relations orders as defined in or meeting the requirements of the Code
or Title I of the Employee Retirement Income Security Act of 1974, as amended
PROVIDED, HOWEVER, that, in the discretion of the Committee, a Non-Statutory
Option may, in connection with a Participant's estate plan, be assigned in whole
or in part during the Participant's lifetime to one or more members of the
Participant's immediate family or to a trust established
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exclusively for one or more such family members. The assigned portion may only
be exercised by the person or persons who acquire a proprietary interest in the
Option pursuant to the assignment. The terms applicable to the assigned portion
shall be the same as those in effect for the Option immediately prior to such
assignment and shall be set forth in such documents issued to the assignee as
the Committee may deem appropriate.

12. CHANGE OF CONTROL

    (a) In the event of a Change of Control, all Awards which have not vested
shall immediately vest upon the occurrence of such Change of Control.

    (b) A "Change of Control" shall be deemed to occur if and when: (i) any
person (including as such term is used in Section 13(d) and 14(d)(2) of the 1934
Act) becomes the beneficial owner, directly or indirectly, of securities
representing 20% or more of the combined voting power of the Corporation'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 the
Corporation's Board of Directors are different than the individuals who served
on the Corporation'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) when the
Corporation's shareholders approve a merger, or consolidation (where in each
case the Corporation is not the survivor thereof), or sale or disposition of all
or substantially all of the Corporation's assets or a plan or partial or
complete liquidation; or (iv) when an offeror (other than the Corporation)
purchases shares of the Corporation's Common Stock pursuant to a tender or
exchange offer for securities representing 20% or more of the combined voting
power of the Corporation's then outstanding securities.

13. AWARD AGREEMENTS

    Each Award under the Plan shall be evidenced by an agreement setting forth
its terms, conditions, and limitations for each Award, and the provisions
applicable in the event the Participant's employment terminates (an "Award
Agreement"). The Committee need not require the execution of any such agreement
by the recipient, in which case acceptance of the Award by the respective
Participant shall constitute agreement by the Participant to the terms and
conditions of the Awards.

14. TAX WITHHOLDING

    The Corporation shall have the right to deduct from any settlement of an
Award made under the Plan, including the delivery or vesting of Shares, or
require the payment of, a sufficient amount to cover withholding of any federal,
state or local or other governmental taxes or charges required by law or such
greater amount of withholding as the Committee shall determine from time to time
and as permitted by applicable laws, rules and regulations, or to take such
other action as may be necessary to satisfy any such withholding obligations. If
the Committee permits or requires Shares to be used to satisfy required tax
withholdings, such Shares shall be valued at the Fair Market Value as of the tax
recognition date for such Award or such other date as may be required by
applicable law, rule or regulation.

15. OTHER BENEFIT AND COMPENSATION PROGRAMS

    Unless otherwise specifically determined by the Committee, settlements of
Awards received by Participants under the Plan shall not be deemed a part of a
Participant's regular, recurring compensation for purposes of calculating
payments or benefits from any Corporation benefit plan or severance program.
Further, the Corporation or any Subsidiary may adopt from time to time other
compensation programs, plans or arrangements as it deems appropriate or
necessary.

16. UNFUNDED PLAN

    Unless otherwise determined by the Committee, the Plan shall be unfunded and
shall not create (or be construed to create) a trust or a separate fund or
funds. The Plan shall not establish any fiduciary relationship between the
Corporation and any participant or other person. To the extent any person holds
any rights by virtue of an Award granted under the Plan, such rights shall
constitute general unsecured liabilities of the Corporation and shall not confer
upon any participant any right, title, or interest in any assets of the
Corporation.

17. REGULATORY APPROVALS

    The implementation of the Plan, the granting of any Award under the Plan,
and the issuance of Shares upon the exercise or settlement or any Award shall be
subject to the Corporation's procurement of all approvals and permits
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required by regulatory authorities having jurisdiction over the Plan, the Awards
granted under it, or the Shares issued pursuant to it.

18. RIGHTS AS A STOCKHOLDER

    A Participant shall have no rights as a stockholder with respect to Shares
covered by an Award until the date the Participant or his nominee is the holder
of record with respect to the Shares covered by such Award. No adjustment will
be made for dividends or other rights for which the record date is prior to such
date, except as may be provided pursuant to Section 9(d) hereunder

19. FUTURE RIGHTS

    No person shall have any claim or right to be granted an Award, and the
grant of an Award shall not be construed as giving a Participant the right to be
retained in the employ of the Corporation or a Subsidiary or to participate in
any other compensation or benefit plan, program or arrangement of the
Corporation or any Subsidiary or to receive any future Award under the Plan. In
addition, the Corporation expressly reserves the right at any time to dismiss a
Participant free from any liability or any claim under the Plan, except as
expressly provided in the Plan or in any Award Agreement entered into hereunder.