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                                                                     EXHIBIT 4.1

                   LABORATORY CORPORATION OF AMERICA HOLDINGS

                            2000 STOCK INCENTIVE PLAN
                      As Amended and Restated April 3, 2002

              1.  Purpose; Restrictions on Amount Available under this Plan.

       This 2000 Stock Incentive Plan, as amended and restated April 3, 2002,
(this "Plan") is intended to encourage stock ownership by employees,
consultants, and non-employee directors of Laboratory Corporation of America
Holdings (the "Company") and employees and consultants of Affiliate Corporations
(as defined in Section 2(a) hereof), so that they may acquire or increase their
proprietary interest in the Company, and to encourage such employees,
consultants and non-employee directors to remain in the employ and/or service of
the Company and to put forth maximum efforts for the success of the business of
the Company. It is further intended that options granted by the Committee
pursuant to Section 6 of this Plan shall constitute "incentive stock options"
("Incentive Stock Options") within the meaning of Section 422 of the Internal
Revenue Code of 1986, as amended, and the regulations issued thereunder (the
"Code"), and options granted by the Committee pursuant to Sections 7 and 8 of
this Plan shall constitute "nonqualified stock options" ("Nonqualified Stock
Options"). Grants under this Plan may consist of Incentive Stock Options,
Nonqualified Stock Options (collectively, "Options"), stock appreciation rights
("Rights"), which Rights may be either granted in conjunction with Options
("Related Rights") or unaccompanied by Options ("Free Standing Rights"),
restricted stock awards ("Restricted Shares"), or performance awards
("Performance Awards"), as hereinafter set forth.

              2.  Definitions.

       As used in this Plan, the following words and phrases shall have the
meanings indicated:

                  (a) "Affiliate Corporation" or "Affiliate" shall mean any
corporation, directly or indirectly, through one or more intermediaries,
controlling, controlled by, or under common control with the Company.

                  (b) "Award" shall mean an Option, a Right, Restricted Share,
or Performance Award granted hereunder.

                  (c) "Award Agreement" shall have the meaning set forth in
Section 3 hereof.

                  (d) "Change in Control" shall mean an event of a nature that:

                      (i) any "person" (as the term is defined in Sections 13(d)
                  and 14(d) of the Securities Exchange Act of 1934, as amended,
                  "the Exchange Act") who is not now presently but becomes the
                  "beneficial owner" (as defined in Rule 13d-3 under the
                  Exchange Act), directly or indirectly, of securities of the
                  Company representing 30% or more of the Company's outstanding
                  securities except for any securities purchased by any
                  tax-qualified employee benefit plan of the Company; or

                      (ii) individuals who constitute the Board of Directors on
                  the Effective Date (the "Incumbent Board") cease for any
                  reason to constitute at least a majority thereof, provided
                  that any person becoming a director subsequent to the date
                  hereof whose election was approved by a vote of at least
                  three-quarters of the directors comprising the Incumbent
                  Board, or whose nomination for election by the Company's
                  stockholders was approved by the Incumbent Board, shall be for
                  purposes of this clause (ii), considered as though he or she
                  were a member of the Incumbent Board; or a plan of
                  reorganization, merger, consolidation, sale of all or
                  substantially

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                  all the assets of the Company or similar transaction occurs in
                  which the Company is not the resulting entity; or

                      (iii) a proxy statement soliciting proxies from
                  shareholders of the Company, by someone other than the current
                  management of the Company, seeking stockholder approval of a
                  plan of reorganization, merger or consolidation of the Company
                  or similar transaction with one or more corporations, as a
                  result of which the outstanding shares of the class of
                  securities not issued by the Company shall be distributed.

                  (e) "Common Stock" shall mean shares of the Company's common
         stock, par value $0.10 per share.

                  (f) "Covered Officer" as of a particular date shall mean (i)
         any individual who, with respect to the previous taxable year of the
         Company, was a "covered employee" of the Company within the meaning of
         Section 162(m) of the Internal Revenue Code; provided, however, that
         the term "Covered Officer" shall not include any such individual who is
         designated by the Committee, in its discretion, at the time of any
         Award or at any subsequent time, as reasonably expected not to be such
         a "covered employee" with respect to the current taxable year of the
         Company and (ii) any individual who is designated by the Committee, in
         its discretion, at the time of any Award or at any subsequent time, as
         reasonably expected to be such a "covered employee" with respect to the
         current taxable year of the Company or with respect to the taxable year
         of the Company in which any applicable Award will be paid.

                  (g) "Disability" shall mean a Participant's inability to
         engage in any substantial gainful activity by reason of medically
         determinable physical or mental impairment that can be expected to
         result in death or that has lasted or can be expected to last for a
         continuous period of not less than twelve (12) months.

                  (h) "Exchange Act" shall mean the Securities Exchange Act of
         1934, as amended.

                  (i) "Fair Market Value" per share as of a particular date
         shall mean (i) the closing sales price per share of Common Stock on a
         national securities exchange for the last preceding date on which there
         was a sale of such Common Stock on such exchange, or (ii) if the shares
         of Common Stock are then traded on an over-the-counter market, the
         average of the closing bid and asked prices for the shares of Common
         Stock in such over-the-market for the last preceding date on which
         there was a sale of such Common Stock in such market, or (iii) if the
         shares of Common Stock are not then listed on a national securities
         exchange or traded in an over-the-counter market, such value as the
         Committee in its discretion may determine.

                  (j) "Parent Corporation" shall mean any corporation (other
         than the Company) in an unbroken chain of corporations ending with the
         Company if, at the time of granting an Award, each of such corporations
         (other than the Company) owns stock possessing fifty percent (50%) or
         more of the total combined voting power of all classes of stock in one
         of the other corporations in such chain.

                  (k) "Participant" shall have the meaning set forth in Section
         4 hereof.

                  (l) "Prior Plans" shall mean the Laboratory Corporation of
         America Holdings Amended and Restated 1999 Stock Incentive Plan and the
         Laboratory Corporation of America Holdings 1994 Stock Option Plan.

                  (m) "Retirement" shall mean a Participant's termination of
         employment in accordance with the provisions of the Company's Employee
         Retirement Plan at such Participant's Normal Retirement Date, as
         defined in such Plan.

                  (n) "Subsidiary Corporation" shall mean any corporation (other
         than the Company) in an unbroken chain of corporations beginning with
         the Company if, at the time of granting an option, each of such
         corporations other than the last corporation in the unbroken chain owns
         stock possessing fifty percent (50%) or more of the total combined
         voting power of all classes of stock in one of the other corporations
         in such chain.
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                  (o) "Ten Percent Stockholder" shall mean a Participant who, at
         the time an Incentive Stock Option is granted, owns stock possessing
         more than ten percent (10%) of the total combined voting power of all
         classes of stock of the Company or of its Parent Corporation or
         Subsidiary Corporations.

           3.   Administration.

         This Plan shall be administered by a committee (the "Committee")
appointed by the Board of Directors of the Company (the "Board"), which shall be
comprised of two or more persons, each of whom shall qualify as a "Non-Employee
Director" as described in Rule 16b-3(b)(3)(i) promulgated under the Exchange
Act.

         The Committee shall have the authority in its discretion, subject to
and not inconsistent with the express provisions of this Plan, to administer
this Plan and to exercise all the powers and authorities either specifically
granted to it under this Plan or necessary or advisable in the administration of
this Plan, including, without limitation, the authority to grant Awards; to
designate Participants, other than as set forth in Section 8 hereof; to
determine the type or types of Awards to be granted to a Participant; to
determine which Options shall constitute Incentive Stock Options and which
Options shall constitute Nonqualified Stock Options; to determine which Rights
(if any) shall be granted in conjunction with Options; to determine the purchase
price of the shares of Common Stock covered by each Option (the "Option Price");
to determine the persons to whom, and the time or times at which, Awards shall
be granted; to determine the number of shares to be covered by each Award; to
interpret this Plan; to prescribe, amend and rescind rules and regulations
relating to this Plan; to determine the terms and provisions of the agreements
(which need not be identical) entered into in connection with Awards granted
under this Plan (each an "Award Agreement"); and to make all other
determinations deemed necessary or advisable for the administration of this
Plan. The Committee may delegate to one or more of its members or to one or more
agents such administrative duties as may be deemed advisable, and the Committee
or any person to whom it has delegated duties as aforesaid may employ one or
more persons to render advice with respect to any responsibility the Committee
or such person may have under this Plan.

         No member of the Board of Directors or Committee shall be liable for
any action taken or determination made in good faith with respect to this Plan
or any Award granted hereunder.

           4.   Eligibility.

         Awards may be granted to key employees (including, without limitation,
officers and directors who are employees) and non-employee directors of the
Company or its present or future Affiliate Corporations. For purposes of the
foregoing, "employee" shall mean any employee, independent contractor,
consultant, advisor, or similar individual who is providing or who has agreed to
provide services to the Company or to any of its present or future Affiliate
Corporations. Notwithstanding any provision of this paragraph, Incentive Stock
Options shall be granted only to individuals who, on the date of such grant, are
employees of the Company or a Parent Corporation or a Subsidiary Corporation. In
determining the persons to whom Awards shall be granted and the number of shares
to be covered by each Award, the Committee shall take into account the duties of
the respective persons, their present and potential contributions to the success
of the Company and such other factors as the Committee shall deem relevant in
connection with accomplishing the purpose of this Plan. A person to whom an
Award has been granted hereunder is sometimes referred to herein as a
"Participant" or "Optionee."

         A Participant shall be eligible to receive more than one grant of an
Award during the term of this Plan, but only on the terms and subject to the
restrictions hereinafter set forth.

           5.   Stock.

         The stock subject to Awards hereunder shall be shares of Common Stock.
Such shares may, in whole or in part, be authorized but unissued shares or
shares that shall have been or that may be reacquired by the Company. The
aggregate number of shares of Common Stock as to which Awards may be granted
from time to time under this Plan shall not exceed 7.4 million, plus any shares
which remain available for grants of awards under the Prior Plans, of which the
number of shares of Common Stock as to which Restricted Shares and/or
Performance Awards may be granted from time to time under this Plan shall not
exceed 3 million. No person may be granted Options or Rights under this Plan
representing an aggregate of more than 300,000 shares of Common Stock in any
year. The

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limitations established by the preceding three sentences shall be subject to
adjustment as provided in Sections 14 and 18 hereof.

         To the extent that (1) any Award granted under the Plan or the Prior
Plans expires, is terminated or forfeited without being exercised, settled or
with respect to Restricted Shares, vested, (2) any Option granted under the Plan
or the Prior Plans is surrendered on exercise of a Right for cash or the
issuance of fewer shares of Common Stock than issuable under such surrendered
Option, or (3) any Free Standing Right granted under the Plan or the Prior Plans
expires or is terminated without being exercised, the shares of Common Stock
issuable thereunder, less such shares issued, shall become available for grants
of Awards.

           6.   Incentive Stock Options.

         Options granted pursuant to this Section 6 are intended to constitute
Incentive Stock Options and shall be subject to the following special terms and
conditions, in addition to the general terms and conditions specified in
Sections 5 and 9 hereof:

                  (a) Value of Shares. The aggregate Fair Market Value
         (determined as of the date the Incentive Stock Option is granted) of
         the shares of Common Stock with respect to which Options granted under
         this Plan and all other option plans of the Company, any Parent
         Corporation and any Subsidiary Corporation become exercisable for the
         first time by a Participant during any calendar year shall not exceed
         $100,000.

                  (b) Ten Percent Stockholders. In the case of an Incentive
         Stock Option granted to a Ten Percent Stockholder, (i) the Option Price
         shall not be less than one hundred ten percent (110%) of the Fair
         Market Value of a share of Common Stock of the Company on the date of
         grant of such Incentive Stock Option, and (ii) the exercise period
         shall not exceed five (5) years from the date of grant of such
         Incentive Stock Option.

           7.   Employee Nonqualified Stock Options.

         Options granted pursuant to this Section 7 are intended to constitute
Nonqualified Stock Options and shall be subject only to the general terms and
conditions specified in Sections 5 and 9 hereof.

           8.   Director Nonqualified Stock Options.

                  (a) Each non-employee director shall be granted an Option to
         purchase that number of shares of Common Stock having a Fair Market
         Value equal to $65,000 as of the date of each annual meeting of the
         stockholders of the Company (the "Annual Grant Amount") following the
         meeting at which the Plan is approved at which such individual is
         elected or reelected to the office of director (the "Meeting Grant
         Date") with each such grant effective as of each Meeting Grant Date. In
         addition, notwithstanding the foregoing, (i) options will be granted to
         directors elected at the meeting at which the Plan is approved for a
         number of shares having a Fair Market Value equal to $65,000 as of the
         Effective Date to be effective as of the Effective Date and (ii) with
         respect to any person who is elected or nominated as and becomes a
         director other than in connection with an annual meeting of the
         stockholders of the Company, such director shall be granted an Option,
         to be effective as of the date of his or her election or appointment,
         in an amount equal to the product of the Annual Grant Amount and a
         fraction the numerator which is the number of months from the date of
         such election or appointment until the expected date of the next annual
         meeting and the denominator of which is twelve. Options granted
         pursuant to this Section 8 are intended to constitute Nonqualified
         Stock Options and shall be subject, to the extent applicable, to the
         general terms and conditions specified in Sections 5 and 9 hereof.

                  (b) No fractional shares shall be issued under this provision.
         Any fractional share that would otherwise be granted in connection with
         the Annual Grant Amount shall be rounded down to the nearest whole
         share, with the remainder being paid in cash.

                  (c) With respect to the Options granted pursuant to this
         Section 8, neither the Board nor the Committee shall have discretion
         with respect to the selection of directors to receive Options, the
         number of

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         shares subject to such Options, the purchase price thereunder or the
         timing of the grant of Options under this Section 8.

                  (d) Unless otherwise provided in an award agreement, the
         Options granted pursuant to this Section 8 shall vest in equal
         one-third installments on each of the three anniversaries following the
         grant date.

           9.   Terms and Conditions of Options.

         Each Option granted pursuant to this Plan shall be evidenced by a
written Award Agreement between the Company and the Participant, which agreement
shall comply with and be subject to the following terms and conditions:

                  (a) Number of Shares. Each Award Agreement shall state the
         number of shares of Common Stock to which the Option relates.

                  (b) Type of Option. Each Award agreement shall specifically
         identify the portion, if any, of the Option that constitutes an
         Incentive Stock Option and the portion, if any, which constitutes a
         Nonqualified Stock Option.

                  (c) Option Price. Each Award Agreement shall state the Option
         Price per share of Common Stock, which shall be not less than one
         hundred percent (100%) of the Fair Market Value of a share of Common
         Stock of the Company on the date of grant of the Option and which, in
         the case of Incentive Stock Options, shall be further subject to the
         limitation described in Section 6(b) hereof. The Option Price shall be
         subject to adjustment as provided in Section 14 hereof. The date on
         which the Committee adopts a resolution expressly granting an Option
         shall be considered the day on which such Option is granted.

                  (d) Medium And Time of Payment. The Option Price shall be paid
         or satisfied in full, at the time of exercise, in cash or in shares of
         Common Stock owned by the Participant for at least six months (which
         are not the subject of any pledge or other security interest) having a
         Fair Market Value equal to such Option Price or in a combination of
         cash and such shares, and may be effected in whole or in part, at the
         discretion of the Committee (i) with monies received from the Company
         at the time of exercise as a compensatory cash payment, or (ii) with
         monies borrowed from the Company pursuant to repayment terms and
         conditions as shall be determined from time to time by the Committee,
         in its discretion separately with respect to each exercise of Options
         and each Participant; provided, however, that each such method and time
         for payment and each such borrowing and terms and conditions of
         security, if any, and repayment shall be permitted by and be in
         compliance with applicable law.

                  (e) Term and Exercise of Options. Options shall be exercisable
         over the exercise period as and at the times and upon the conditions
         that the Committee may determine, as reflected in the Award Agreement;
         provided, however, that the Committee shall have the authority to
         accelerate the exercisability of any outstanding Option at such time
         and under such circumstances as it, in its sole discretion, deems
         appropriate. The exercise period shall be determined by the Committee;
         provided, however, that in the case of any Incentive Stock Option, such
         exercise period shall not exceed ten (10) years from the date of grant
         of such Incentive Stock Option and such exercise period shall be
         further limited in circumstances described in Section 6(b) hereof. The
         exercise period shall be subject to earlier termination as provided in
         Section 9(f) and 9(g) hereof. An Option may be exercised as to any or
         all full shares of Common Stock as to which the Option has become
         exercisable, by giving written notice of such exercise to the
         Committee; provided, however, that an Option may not be exercised at
         any one time as to fewer than one hundred (100) shares (or such number
         of shares as to which the Option is then exercisable if such number of
         shares is less than one hundred (100)).

                  (f) Termination of Employment. Except as provided in this
         Section 9(f) and in Section 9(g) hereof, an Option may not be exercised
         unless the Participant is then in the employ or service of (1) the
         Company, (2) an Affiliate Corporation or (3) a corporation issuing or
         assuming the Option in a transaction to which Section 424 of the Code
         applies or a parent corporation or subsidiary corporation of the

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         corporation described in this Clause 3, and unless the Participant has
         remained continuously so employed since the date of grant of the
         Option. In the event that the employment or service of a Participant
         shall terminate (other than by reason of death, Disability or
         Retirement), all Options of such Participant that are exercisable at
         the time of such termination may, unless earlier terminated in
         accordance with their terms, be exercised within three (3) months after
         such termination. Nothing in this Plan or in any Option or Right
         granted pursuant hereto shall confer upon an individual any right to
         continue in the employ or service of the Company or any of its
         Affiliate Corporations or interfere in any way with the right of the
         Company or any such Affiliate Corporation to terminate such employment
         or service at any time.

                  (g) Acceleration of Benefits upon Death, Disability or
         Retirement of Participant or a Change in Control. If (i) a Participant
         shall die while employed by the Company or an Affiliate Corporation
         thereof, (ii) a Participant shall die within three (3) months after the
         termination of such Participant's employment, (iii) the Participant's
         employment shall terminate by reason of Disability or Retirement, or
         (iv) there is a Change in Control, then in any such case all Options
         theretofore granted to such Participant (whether or not then
         exercisable) may, unless earlier terminated or expired in accordance
         with their terms, be exercised by the Participant or by the
         Participant's estate or by a person who acquired the right to exercise
         such Option by bequest or inheritance or otherwise by reason of the
         death or Disability of the Participant, at any time within one year
         after the date of death, Disability or Retirement of the Participant or
         the Change in Control.

                  (h) Nontransferability of Options. Except as otherwise
         provided in an Award Agreement, Options granted under this Plan shall
         not be transferable otherwise than by will or by the laws of descent
         and distribution, and Options may be exercised, during the lifetime of
         the Participant, only by the Participant or by his guardian or legal
         representative.

                  (i) Rights as a Stockholder. A Participant who is the holder
         of an Option or a transferee of an Option shall have no rights as a
         stockholder with respect to any shares covered by the Option until the
         date of the issuance of a stock certificate to him or her for such
         shares. No adjustment shall be made for dividends (ordinary or
         extraordinary, whether in cash, securities or other property) or
         distribution of other rights for which the record date is prior to the
         date such stock certificate is issued, except as provided in Section 14
         hereof.

                  (j) Other Provisions. The Award Agreements authorized under
         this Plan shall contain such other provisions, including, without
         limitation, (i) the granting of Rights, (ii) the imposition of
         restrictions upon the exercise of an Award, and (iii) in the case of an
         Incentive Stock Option, the inclusion of any condition not inconsistent
         with such Option qualifying as an Incentive Stock Option, as the
         Committee shall deem advisable.

          10.  Stock Appreciation Rights.

                  (a) Grant and Exercise. In the case of a Nonqualified Stock
         Option, Related Rights may be granted either at or after the time of
         the grant of such Option. In the case of an Incentive Stock Option,
         related Rights may be granted only at the time of the grant of the
         Incentive Stock Option.

         A Related Right or applicable portion thereof granted with respect to a
given Option shall terminate and no longer be exercisable upon the termination
or exercise of the related Option, except that, unless otherwise provided by the
Committee at the time of grant, a Related Right granted with respect to less
than the full number of shares covered by a related Option shall only be reduced
if and to the extent that the number of shares covered by the exercise or
termination of the related Option exceeds the number of shares not covered by
the Right.

         A Related Right may be exercised by a Participant, in accordance with
paragraph (b) of this Section 10, by surrendering the applicable portion of the
related Option. Upon such exercise and surrender, the Participant shall be
entitled to receive an amount determined in the manner prescribed in paragraph
(b) of this Section 10. Options, which have been so surrendered, in whole or in
part, shall no longer be exercisable to the extent the Related Rights have been
exercised.

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                  (b) Terms and Conditions. Rights shall be subject to such
         terms and conditions, not inconsistent with the provisions of this
         Plan, as shall be determined from time to time by the Committee and as
         evidenced by a written Award Agreement between the Company and the
         Participant, including the following:

                         (i)    Related Rights shall be exercisable only at such
                  time or times and to the extent that the Options to which they
                  relate shall be exercisable in accordance with the provisions
                  of Section 6, 7, 9 and this Section 10 of this Plan.

                         (ii)   Upon the exercise of a Related Right, a
                  Participant shall be entitled to receive up to, but not more
                  than, an amount in cash or shares of Common Stock equal in
                  value to the excess of the Fair Market Value of one (1) share
                  of Common Stock over the option price per share specified in
                  the related Option multiplied by the number of shares in
                  respect of which the Related Right shall have been exercised,
                  with the Committee having the right to determine the form of
                  payment.

                         (iii)  Related Rights shall be transferable only when
                  and to the extent that the underlying Option would be
                  transferable under paragraph (h) of Section 9 of this Plan.

                         (iv)   A Related Right granted in connection with an
                  Incentive Stock Option may be exercised only if and when the
                  market price of the Common Stock subject to the Incentive
                  Stock Option exceeds the exercise price of such Option.

                         (v)    Free Standing Rights shall be exercisable at
                  such time or times and subject to such terms and conditions as
                  shall be determined by the Committee at or after grant.

                         (vi)   The term of each Free Standing Right shall be
                  fixed by the Committee, but no Free Standing Right shall be
                  exercisable more than ten (10) years after the date such right
                  is granted.

                         (vii)  Upon the exercise of a Free Standing Right, a
                  Participant shall be entitled to receive up to, but not more
                  than, an amount in cash or shares of Common Stock equal in
                  value to the excess of the Fair Market Value of one share of
                  Common Stock over the price per share specified in the Free
                  Standing Right (which shall be no less than one hundred
                  percent (100%) of the Fair Market Value of the Common Stock on
                  the date of grant) multiplied by the number of shares in
                  respect of which the Right is being exercised, with the
                  Committee having the right to determine the form of payment.

                         (viii) No Free Standing Right shall be transferable by
                  the Participant otherwise than by will or by the laws of
                  descent and distribution, and all such rights shall be
                  exercisable, during the Participant's lifetime, only by the
                  Participant or his legal guardian or legal representative.

                         (ix)   In the event of the termination of employment of
                  a recipient of a Free Standing Right, such right shall be
                  exercisable to the same extent that an Option would have been
                  exercisable in the event of the termination of employment of a
                  Participant.

          11.  Restricted Shares.

                    (a) Grant. Subject to the provisions of this Plan, the
         Committee shall have sole and complete authority to determine the
         Participants to whom Restricted Shares shall be granted, the number of
         Restricted Shares to be granted to each Participant, the duration of
         the period during which, and the conditions under which, the Restricted
         Shares may be forfeited to the Company, and the other terms and
         conditions of such Awards (including whether or not such Restricted
         Shares shall qualify as Performance Awards).

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                  (b) Transfer Restrictions. Restricted Shares may not be sold,
         assigned, transferred, pledged or otherwise encumbered, except as
         otherwise provided in an Award Agreement. Certificates issued in
         respect of Restricted Shares shall be registered in the name of the
         Participant and deposited by such Participant, together with a stock
         power endorsed in blank, with the Company. Upon the lapse of the
         restrictions applicable to such Restricted Shares, the Company shall
         deliver such certificates to the Participant or the Participant's legal
         representative.

                  (c) Dividends and Distributions. Dividends and other
         distributions paid on or in respect of Restricted Shares, if any, may
         be paid directly to the Participant, or may be reinvested in additional
         Restricted Shares, as determined by the Committee in its sole
         discretion.

                  (d) Acceleration of Benefits upon Death, Disability or
         Retirement of Participant or a Change in Control. If (i) a Participant
         shall die while employed by the Company or an Affiliate Corporation
         thereof, (ii) the Participant's employment shall terminate by reason of
         Disability or Retirement, or (iii) there is a Change in Control, then
         in any such case all Restricted Shares theretofore granted to such
         Participant shall become immediately vested and nonforfeitable.

          12.   Performance Awards.

                  (a) Grant. Subject to the provisions of this Plan, the
         Committee shall have sole and complete authority to determine the
         Participants to whom Performance Awards shall be granted, the number of
         shares of Common Stock subject to Performance Awards, the duration of
         the period during which, and the conditions under which, the
         Performance Awards may be forfeited to the Company, and the other terms
         and conditions of such Awards. Performance Awards may be (i)
         denominated in cash or Shares, (ii) valued, as determined by the
         Committee, in accordance with the achievement of such performance goals
         during such performance periods as the Committee shall establish, and
         (iii) payable at such time and in such form as the Committee shall
         determine.

                  (b) Terms and Conditions. Subject to the terms of the Plan and
         any applicable Award Agreement, the Committee shall determine the
         performance goals to be achieved during any performance period, the
         length of any performance period, the amount of any Performance Award
         and the amount and kind of any payment or transfer to be made pursuant
         to any Performance Award. Unless otherwise provided in an Award
         Agreement, Performance Awards may not be sold, assigned, transferred,
         pledged or otherwise encumbered.

                  (c) Payment of Performance Awards.  Performance Awards may be
         paid in a lump sum or in installments following the close of the
         performance period or, in accordance with procedures established by the
         Committee, on a deferred basis.

          13.   Provisions Applicable to Covered Officers.

         To the extent the Committee determines, all performance-based
Restricted Shares and Performance Awards granted to Covered Officers shall be
subject to the terms and provisions of this Section 13.

                  (a) Performance goals shall be limited to one or more of the
         following Company, subsidiary, operating unit or division financial
         performance measures:

                           (i)   earnings before interest, taxes, depreciation
                                 and/or amortization

                          (ii)   operating income or profit

                         (iii)   return on equity, assets, capital, capital
                                 employed, or investment

                          (iv)   after tax operating income

                           (v)   net income

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                          (vi)   earnings or book value per share

                         (vii)   cash flow(s)

                        (viii)   total sales or revenues or sales or revenues
                                 per employee

                          (ix)   stock price or total shareholder return

                           (x)   dividends

                          (xi)   strategic business objectives, consisting of
                  one or more objectives based on meeting specified cost
                  targets, business expansion goals, and goals relating to
                  acquisitions or divestitures or any combination thereof. Each
                  goal may be expressed on an absolute and/or relative basis,
                  may be based on or otherwise employ comparisons based on
                  internal targets, the past performance of the Company and/or
                  the past or current performance of other companies, and in the
                  case of earnings-based measures, may use or employ comparisons
                  relating to capital, shareholders' equity and/or shares
                  outstanding, or to assets or net assets.

                  (b) The maximum annual number of shares in respect of which
         performance-based Restricted Shares and Performance Awards may be
         granted to any Participant under the Plan is 200,000 and the maximum
         annual amount of any such Award settled per Participant in cash is $5
         million.

                  (c) To the extent necessary to comply with Section 162(m), no
         later than 90 days following the commencement of each performance
         period (or such other time as may be required or permitted by Section
         162(m) of the Code), the Committee shall, in writing, (A) select the
         performance goal or goals applicable to the performance period, (B)
         establish the various targets and bonus amounts which may be earned for
         such performance period and (C) specify the relationship between
         performance goals and targets and the amounts to be earned by each
         Covered Officer for such performance period. Following the completion
         of each performance period, the Committee shall certify in writing
         whether the applicable performance targets have been achieved and the
         amounts, if any, payable to Covered Officers for such performance
         period. In determining the amount earned for a given performance
         period, subject to any applicable Award Agreement, the Committee shall
         have the right to reduce (but not increase) the amount payable at a
         given level of performance to take into account additional factors that
         the Committee may deem relevant to the assessment of individual or
         corporate performance for the performance period.

          14.   Effect of Certain Changes.

                  (a) If there is any change in the number of outstanding shares
         of Common Stock by reason of any stock dividend, stock split,
         recapitalization, combination, exchange of shares, merger,
         consolidation, liquidation, split-up, spin-off or other similar change
         in capitalization, any distribution to shareholders, including a rights
         offering, other than cash dividends, or any like change, then the
         number of shares of Common Stock available for Awards, the maximum
         number of shares of Common Stock that may be subject to Awards, the
         number of such shares of Common Stock covered by outstanding Awards,
         and the price per share of Options or the applicable market value of
         Rights, shall be proportionately adjusted by the Committee to reflect
         such change or distribution; provided, however, that any fractional
         shares resulting from such adjustment shall be eliminated.

                  (b) In the event of a change in the Common Stock as presently
         constituted, which is limited to a change of all of its authorized
         shares with par value into the same number of shares with a different
         par value or without par value, the shares resulting from any such
         change shall be deemed to be Common Stock within the meaning of this
         Plan.

                  (c) To the extent that the foregoing adjustments relate to
         stock or securities of the Company, such adjustments shall be made by
         the Committee, whose determination in that respect shall be final,
         binding and conclusive, provided that each Incentive Stock Option
         granted pursuant to this Plan shall not

                                       9

<PAGE>

         be adjusted in a manner that causes such option to fail to continue to
         qualify as an Incentive Stock Option within the meaning of Section 422
         of Code.

          15.   Agreement by Participant Regarding Withholding Taxes.

         If the Committee shall so require, as a condition of grant, exercise,
or settlement or otherwise, each Participant shall agree that:

                  (a) no later than the date a Participant recognizes taxable
         income in connection with an Award granted hereunder in connection with
         the exercise or settlement of such Award or otherwise, the Participant
         will pay to the Company or make arrangements satisfactory to the
         Committee regarding payment of any federal, state or local taxes of any
         kind required by law to be withheld upon the exercise or settlement of
         such Award (any such tax, a "Withholding Tax"); and

                  (b) the Company shall, to the extent permitted or required by
         law, have the right to deduct any Withholding Tax from any payment of
         any kind otherwise due to the Participant.

          16.   Gross-Up for Excise Tax.

         An Award Agreement may provide that in the event that a Participant
becomes entitled by reason of a Change of Control to the accelerated vesting of
an Award, if such Participant will be subject to excise tax (the "Excise Tax")
under Section 4999 of the Code, the Company shall pay to such Participant as
additional compensation an amount (the "Gross-Up Payment") which, after payment
by such Participant of all taxes (including any federal, state and local income
tax and excise tax upon the payment provided for by this Section 16) allows
Participant to retain an amount of the Gross-Up Payment equal to the Excise Tax.
For purposes of determining whether a Participant will be subject to the Excise
Tax and the amount of such Excise Tax, (i) any other payments or benefits
received or to be received by such Participant in connection with a Change in
Control of the Company or the Participant's termination of employment (whether
pursuant to the terms of the Award Agreement or any other plan, arrangement or
agreement with the Company, any entity whose actions result in a Change in
Control of the Company or any entity affiliated with the Company or such entity)
shall be treated as "parachute payments" within the meaning of Section
280G(b)(2) of the Code, and all "excess parachute payments" within the meaning
of Section 280G(b)(1) of the Code shall be treated as subject to the Excise Tax,
unless in the opinion of tax counsel selected by the Company's independent
auditors and reasonably acceptable to the Participant such other payments or
benefits (in whole or in part) do not constitute parachute payments, including
by reason of Section 280G(b)(4)(A) of the Code, or such excess parachute
payments (in whole or in part) represent reasonable compensation for services
actually rendered, within the meaning of Section 280G(b)(4)(B) of the Code, or
are otherwise not subject to the Excise Tax, (ii) the amount of payments or
benefits treated as subject to the Excise Tax shall be equal to the lesser of
(A) the total amount of payments or benefits conferred on such Participant by
reason of the Change of Control or (B) the amount of excess parachute payments
within the meaning of Section 280G(b)(1) of the Code (after applying clause (i),
above), and (iii) the value of any noncash benefits or any deferred payment or
benefit shall be determined by the Company's independent auditors in accordance
with the principles of Sections 280G(d)(3) and (4) of the Code. For purposes of
determining the amount of the Gross-Up Payment, the Participant shall be deemed
to pay federal income taxes at the highest marginal rate of federal income
taxation in the calendar year in which the Gross-Up Payment is to be made and
state and local income taxes at the highest marginal rate of taxation in the
state and locality of the Participant's residence on the date on which the
Excise Tax is incurred, net of the maximum reduction in federal income taxes
which could be obtained from deduction of such state and local taxes. In the
event that the Excise Tax is subsequently determined to be less than the amount
taken into account hereunder, the Participant shall repay to the Company, at the
time that the amount of such reduction in Excise Tax is finally determined, the
portion of the Gross-Up Payment attributable to such reduction (plus that
portion of the Gross-Up Payment attributable to the Excise Tax and federal,
state and local income tax deduction) plus interest on the amount of such
repayment at the rate provided in Section 1274(b)(2)(B) of the Code. In the
event that the Excise Tax is determined to exceed the amount taken into account
hereunder (including by reason of any payment the existence or amount of which
cannot be determined at the time of the Gross-Up Payment), the Company shall
make an additional Gross-Up Payment in respect of such excess (plus any
interest, penalties or additions payable by the Participant with respect to such
excess) at the time that the amount of such excess finally is determined. The
Participant and the

                                       10

<PAGE>

Company each shall reasonably cooperate with the other in connection with any
administrative or judicial proceedings concerning the existence or amount of
liability for Excise Tax.

          17.   Termination and Amendment.

         Unless terminated by action of the Board of Directors or the Committee,
no Awards may be granted under this Plan after May 4, 2010. This Plan may be
amended or terminated at any time by the Committee, except that no amendment may
be made without shareholder approval if the Committee determines that such
approval is necessary to comply with any tax or regulatory requirement,
including any approval requirement which is a prerequisite for exemptive relief
from Section 16 of the Exchange Act, for which or with which the Committee
determines that it is desirable to qualify or comply. The Committee may amend
the terms of any Award Agreement and any Award granted, retroactively or
prospectively, but no amendment may adversely affect any vested Award without
the holder's consent.

          18.   Effectiveness; Approval of Stockholders.

         Except as otherwise provided herein, this amended and restated Plan
shall take effect as of May 15, 2002 (the "Effective Date"), subject to the
approval of the holders of the majority of the voting shares of the Company at
the Company's 2002 annual meeting of Stockholders (the "2002 Annual Meeting").
If the Plan amendments to increase from 3.4 million to 7.4 million the number of
authorized shares for issuance under such plan and to increase from 1.5 million
to 3 million the number of shares of common stock as to which Restricted Shares
and/or Performance Awards may be granted under such plan are not approved by the
holders of the majority of the voting shares of the Company, this Plan will be
restated so that the number of shares of Common Stock authorized for issuance
shall be adjusted so that the limitations set forth therein shall revert to the
unamended Plan. The limitations established by the preceding sentence shall be
subject to adjustment as provided in Sections 14 hereof.

          19.   Effect of Headings.

         The section and subsection headings contained herein are for
convenience only and shall not affect the construction hereof.

          20.   Governing Law

         The validity, construction and effect of the Plan shall be determined
in accordance with the laws of the State of Delaware.

                                       11

<PAGE>

                         FORM OF STOCK OPTION AGREEMENT

THIS AGREEMENT dated as of the ___ day of __________, ____ between Laboratory
Corporation of America Holdings, a Delaware corporation (the "Company") and
((First_Name)) ((MI)) ((Last_Name)) (the "Employee").

                                   WITNESSETH

In consideration of the mutual promises and covenants made herein and the mutual
benefits to be derived herefrom, the parties hereto agree as follows:

1.   Grant of Options.

Subject to the provisions of this Agreement and to the provisions of the
Laboratory Corporation of America Holdings Amended and Restated 2000 Stock
Incentive Plan (the "Plan"), the Company hereby grants to the Employee the right
and option (the "Option") to purchase all or any part of the number of shares of
common stock, par value $0.10 per share ("Common Stock") of the Company, set
forth on Schedule A attached hereto at the price per share and on the other
terms set forth on Schedule A.

2.   Exercisability of Options.

One-third (1/3) of the shares subject to the Options may be purchased by the
Employee pursuant to exercise of the Options on or after ________________, an
additional one-third (1/3) of such shares on or after ________________, and all
of such shares on or after ________________, in each case subject to the prior
expiration or sooner termination of the Options; provided, however, that Options
may not be exercised at any one time as to fewer than 100 shares (or such number
of shares as to which the Options are then exercisable if such number of shares
is less than 100).

3.   Method of Exercise of the Options.

     (a) The Options as to which the Employee is vested shall be exercisable by
delivery to the Company of a written notice stating the number of shares to be
purchased pursuant to this Agreement and accompanied by payment for the full
purchase price of the shares to be purchased. Fractional share interests shall
be disregarded except that they may be accumulated.

     (b) The exercise price shall be paid in cash or by certified check or bank
draft payable to the order of the Company, or by exchange of Common Stock of the
Company having an aggregate fair market value equal to the aggregate exercise
price, or by a combination of the foregoing.

4.   Termination of Employment.

Except as provided in Paragraph 4 and in Paragraph 5 hereof, Options may not be
exercised unless the Employee is then in the employ of (i) the Company, (ii) an
affiliated corporation or (iii) a corporation issuing or assuming the Options in
a transaction to which Section 424 and/or 425(a) of the Internal Revenue Code of
1986 applies or a parent corporation or subsidiary corporation of the
corporation described in the clause (iii), and unless the Employee has remained
continuously so employed since the date of grant of the Options. In the event
that the employment of the Employee shall terminate (other than by reason of
death, disability or retirement), all Options of such Employee that are
exercisable at the time of such termination may, unless earlier terminated in
accordance with their terms, be exercised within three (3) months after such
termination, subject to the restrictions on sales of securities imposed by the
LabCorp Insider Trading Policy including, without limitation, any applicable
mandatory "black-out periods."

Nothing in this Agreement or the Plan shall confer upon the Employee any right
to continue in the employ of the Company or any of its affiliate corporations or
interfere in any way with the right of the Company or any such affiliate
corporation to terminate such employment at any time.

5.   Acceleration of Benefits Upon Death, Disability or Retirement of Employee
     or Change in Control.

If (i) Employee shall die while employed by the Company or an affiliate
corporation thereof, (ii) the Employee shall die within three (3) months after
the termination of the Employee's employment, (iii) the Employee's employment
shall terminate by reason of Disability or Retirement (as defined in the Plan)
or (iv) there is a termination as a result of a Change in Control (as defined in
the Plan), all Options granted pursuant to this Agreement which are vested and
which have not been exercised may, unless earlier terminated in accordance with
their terms, be exercised by the

<PAGE>

Employee or by the Employee's estate or by a person who acquired the right to
exercise such Options by bequest or inheritance or otherwise by reason of the
death or disability of the Employee, at any time within one (1) year after the
date of Death, Disability or Retirement of the Employee or the Change in
Control, subject to the restrictions on sales of securities imposed by the
LabCorp Insider Trading Policy including, without limitation, any applicable
mandatory "black-out periods."

6.   Nontransferability of Options.

The Options are non-transferable by the Employee other than by will or the laws
of descent and distribution, and Options may be exercised during the lifetime of
the Employee only by the Employee or by his guardian or legal representative.

7.   Effect of Certain Changes.

     (a) If there is any change in the number of outstanding shares of Common
Stock by reason of any stock dividend, stock split, recapitalization,
combination, exchange of shares, merger, consolidation, liquidation, split-up,
spin-off or other similar change in capitalization, any distribution to common
shareholders, including a rights offering, other than cash in dividends, or any
like change, the number of shares covered by outstanding Options granted
pursuant to this Agreement, and the price per share of such Options, shall be
proportionately adjusted by the Committee (as defined in the Plan) to reflect
any such change or distributing provided, however, that any fractional shares
resulting form such adjustment shall be eliminated.

     (b) In the event of a change in the Common Stock of the Company as
presently constituted, which is limited to a change of all of its authorized
shares with par value into the same number of shares with different par value or
without par value, the shares resulting from any such change shall be deemed to
be Common Stock within the meaning of this Agreement and the Plan.

     (c) To the extent that the foregoing adjustments relate to stock or
securities of the Company, such adjustments shall be made by the Committee,
whose determination in that respect shall be final, binding and conclusive.

8.   Rights as a Stockholder.

An Employee or a transferee of Options shall have no rights as a stockholder
with respect to any shares covered by such Options until the date of the
issuance of a stock certificate to such individual for such shares. No
adjustment shall be made for dividends (ordinary or extraordinary, whether in
cash, securities or other property) or distribution of other rights for which
the record date is prior to the date a stock certificate is issued, except as
provided in Paragraph 7 of this Agreement.

9.   Payment of Transfer Taxes, Fees, and Other Expenses.

The Company agrees to pay any and all original issue taxes and stock transfer
taxes that may be imposed on the issuance of shares acquired pursuant to the
exercise of the Options, together with any and all the fees and expenses
necessarily incurred by the Company in connection therewith.

10.  Other Restrictions.

The exercise of each Option shall be subject to the requirement that, if at any
time the Committee shall determine that (i) the listing, registration or
qualification of the shares of Common Stock subject or related thereto upon any
securities, exchange or under any state or federal law, or (ii) the consent or
approval of any government regulatory body, or (iii) an agreement by the
Employee with respect to the disposition of shares of Common Stock, is necessary
or desirable as a condition of, or in connection with, such exercise or the
delivery or purchase of shares pursuant thereto, then in any such event, such
exercise shall not be effective unless such listing, registration,
qualification, consent, approval or agreement shall have been effected or
obtained free of any conditions not acceptable to the Committee.

11.  Taxes and Withholding.

No later than the date of exercise of any Options granted hereunder, the
Employee shall pay to the Company or make arrangements satisfactory to the
Committee regarding payment of any federal, state or local taxes of any kind
required by law to be withheld upon the exercise of such Options and the Company
shall, to the extent permitted or required by law, have the right to deduct from
any payment of any kind otherwise due to the Employee, federal, state and local
taxes of any kind required by law to be withheld upon the exercise of such
Options.

                                       2

<PAGE>

12.  Notices.

Any notices to be given under the terms of this Agreement shall be in writing
and addressed to the Company at 430 South Spring Street, Burlington, North
Carolina 27215, Attention: Corporate Secretary and to the Employee at the
address set forth on Schedule A, or at such address as either party may
hereafter designate in writing to the other.

13.  Effect of Agreement.

Except as otherwise provided hereunder, this Agreement shall be binding upon and
shall inure to the benefit of any successor or successors of the Company.

14.  Law Applicable to Construction.

The Options have been granted, executed and delivered in the State of New York,
and the interpretation, performance and enforcement of this Agreement shall be
governed by the laws of the State of New York, as applied to contracts executed
in and performed wholly within the State of New York.

15.  Conflicts and Interpretation.

If there is any conflict between this Agreement and the Plan, or if there is any
ambiguity in this Agreement, any term which is not defined in this Agreement, or
any matter as to which this Agreement is silent, in any such case, the Plan
shall govern including, without limitation, the provisions thereof pursuant to
which the Committee has the power, among others, to (i) interpret the Plan, (ii)
prescribe, amend and rescind rules and regulations relating to the Plan and
(iii) make all other determinations deemed necessary or advisable for the
administration of the Plan.

16.  Headings.

The headings of paragraphs herein are included solely for convenience of
reference and shall not affect the meaning or interpretation of any of the
provisions of this Agreement.

17.  Amendment.

This Agreement may not be modified, amended or waved in any manner except by an
instrument in writing signed by both parties hereto. The waiver by either party
of compliance with any provision of this Agreement shall not operate or be
construed as a waiver of any other provision of this Agreement, or of any
subsequent breach by such party of a provision of this Agreement.

IN WITNESS WHEREOF, the Company has caused this Agreement to be executed on its
behalf by a duly authorized officer and the Employee has hereunto set his/her
hand, effective as of the day and year first above written.

                                LABORATORY CORPORATION OF AMERICA HOLDINGS

                                By: ____________________________________________
                                        Thomas P. MacMahon, Chairman and CEO


                                                EMPLOYEE

                                By: __________________________________________
                                        First Name, Middle Initial, Last Name

                                       3

<PAGE>

                      Schedule A to Stock Option Agreement

Employee Name and Address:
((First_Name)) ((MI)) ((Last_Name))
((Address))
((City)), ((State)) ((Zip))


Employee Social Security Number:

((SSN))

Number and Type of Options:
((Options)) non-qualified options


Exercise Price:
$_______ per share

Vesting:

1/3 on or after ________________________
1/3 on or after ________________________
100% on or after _______________________


Expiration of Options:
                                  __________________

                                       4