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                                                                  Exhibit 10(a)

                                MERCK & CO., INC.

                            2001 INCENTIVE STOCK PLAN

                           (effective January 1, 2001)

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                           2001 INCENTIVE STOCK PLAN

       The 2001 Incentive Stock Plan ("ISP"), effective January 1, 2001, is
established to encourage employees of Merck & Co., Inc. (the "Company"), its
subsidiaries, its affiliates and its joint ventures to acquire Common Stock in
the Company ("Common Stock"). It is believed that the ISP will stimulate
employees' efforts on the Company's behalf, will tend to maintain and strengthen
their desire to remain with the Company, will be in the interest of the Company
and its Stockholders and will encourage such employees to have a greater
personal financial investment in the Company through ownership of its Common
Stock.

1.     INCENTIVES

       Incentives under the ISP may be granted in any one or a combination of
(a) Incentive Stock Options (or other statutory stock options); (b) Nonqualified
Stock Options; (c) Stock Appreciation Rights; (d) Restricted Stock Grants and
(e) Performance Shares (collectively "Incentives"). All Incentives shall be
subject to the terms and conditions set forth herein and to such other terms and
conditions as may be established by the Compensation and Benefits Committee of
the Board of Directors (the "Committee").

2.     ELIGIBILITY

       Regular full-time and part-time employees of the Company, its
subsidiaries, its affiliates and its joint ventures, including officers, whether
or not directors of the Company, and employees of a joint venture partner or
affiliate of the Company who provide services to the joint venture with such
partner or affiliate, shall be eligible to participate in the ISP ("Eligible
Employees") if designated by the Committee. Directors of the Company who are not
regular employees are not eligible to participate in the ISP.

3.     ADMINISTRATION

       The ISP shall be administered by the Committee. The Committee shall be
responsible for the administration of the ISP including, without limitation,
determining which Eligible Employees receive Incentives, what kind of Incentives
are made under the ISP and for what number of shares, and the other terms and
conditions of such Incentives. Determinations by the Committee under the ISP
including, without limitation, determinations of the Eligible Employees, the
form, amount and timing of Incentives, the terms and provisions of Incentives
and the agreements evidencing Incentives, need not be uniform and may be made
selectively among Eligible Employees who receive, or are eligible to receive,
Incentives hereunder, whether or not such Eligible Employees are similarly
situated.

       The Committee shall have the responsibility of construing and
interpreting the ISP and of establishing and amending such rules and regulations
as it may deem necessary or desirable for the proper administration of the ISP.
Any decision or action taken or to be taken by the Committee, arising out of or
in connection with the construction, administration, interpretation and effect
of the ISP and of its rules and regulations, shall, to the maximum extent
permitted by applicable law, be within its absolute discretion (except as
otherwise specifically provided herein) and shall be conclusive and binding upon
the Company, all Eligible Employees and any person claiming under or through any
Eligible Employee.

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       The Committee may delegate some or all of its power and authority
hereunder to the Chief Executive Officer or other senior member of management as
the Committee deems appropriate; provided, however, that the Committee may not
delegate its authority with regard to any matter or action affecting an officer
subject to Section 16 of the Securities Exchange Act of 1934.

       For the purpose of this section and all subsequent sections, the ISP
shall be deemed to include this plan and any comparable sub-plans established by
subsidiaries which, in the aggregate, shall constitute one plan governed by the
terms set forth herein.

4.     SHARES AVAILABLE FOR INCENTIVES

       (a) SHARES SUBJECT TO ISSUANCE OR TRANSFER. Subject to adjustment as
provided in Section 4(c) hereof, there is hereby reserved for issuance under the
ISP 95 million shares of Common Stock. The shares available for granting awards
shall be increased by the number of shares as to which options or other benefits
granted under the ISP have lapsed, expired, terminated or been canceled. In
addition, any shares reserved for issuance under the Company's 1996 Incentive
Stock Plan and 1991 Incentive Stock Plan ("Prior Plans") in excess of the number
of shares as to which options or other benefits have been awarded thereunder,
plus any such shares as to which options or other benefits granted under the
Prior Plans may lapse, expire, terminate or be canceled, shall also be reserved
and available for issuance or reissuance under the ISP. Shares under this ISP
may be delivered by the Company from its authorized but unissued shares of
Common Stock or from Common Stock held in the Treasury.

       (b) LIMIT ON AN INDIVIDUAL'S INCENTIVES. In any given year, no Eligible
Employee may receive Incentives covering more than three (3) million shares of
the Company's Common Stock (such number of shares shall be adjusted in
accordance with Section 4(c)).

       (c) ADJUSTMENT OF SHARES. In the event of a reorganization,
recapitalization, stock split, stock dividend, combination of shares, merger,
consolidation, rights offering or other similar change in the capital structure
of the Company, then (i) the number of shares authorized for issuance under the
ISP, and (ii) the number of shares subject to outstanding Incentives and, in the
case of Stock Options, the option price, and in the case of stock appreciation
rights, the fair market value, will be proportionately adjusted, provided that
fractions of a share will be rounded down to the nearest whole share.

5.     STOCK OPTIONS

       The Committee may grant options qualifying as Incentive Stock Options
under the Internal Revenue Code of 1986, as amended, or any successor code
thereto (the "Code"), other statutory options under the Code and Nonqualified
Options (collectively "Stock Options"). Such Stock Options shall be subject to
the following terms and conditions and such other terms and conditions as the
Committee may prescribe:

              (a) OPTION PRICE. The option price per share with respect to each
       Stock Option shall be determined by the Committee, but shall not be less
       than 100% of the fair market value of the Common Stock on the date the
       Stock Option is granted, as determined by the Committee.

              (b) PERIOD OF OPTION. The period of each Stock Option shall be
       fixed by the Committee, but shall not exceed ten (10) years.

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              (c) PAYMENT. No shares shall be issued until full payment of the
       option price has been made. The option prices may be paid in cash or, if
       the Committee determines, in shares of Common Stock or a combination of
       cash and shares. If the Committee approves the use of shares of Common
       Stock as a payment method, the Committee shall establish such conditions
       as it deems appropriate for the use of Common Stock to exercise a stock
       option. Stock options awarded under the ISP shall be exercised through
       the Company's broker-assisted stock option exercise program, provided
       such program is available at the time of the option exercise, or by such
       other means as the Committee may determine from time to time. The
       Committee may establish rules and procedures to permit an optionholder to
       defer recognition of gain upon the exercise of a stock option.

              (d) EXERCISE OF OPTION. The Committee shall determine how and when
       shares covered by a Stock Option may be purchased. The Committee may
       establish waiting periods, the dates on which options become exercisable
       or "vested" and exercise periods, provided that in no event (including
       those specified in paragraphs (e), (f) and (g) of this section) shall any
       Stock Option be exercisable after its specified expiration period.

              (e) TERMINATION OF EMPLOYMENT. Upon the termination of a Stock
       Option grantee's employment (for any reason other than retirement, death
       or termination for deliberate, willful or gross misconduct), Stock Option
       privileges shall be limited to the shares which were immediately
       exercisable at the date of such termination. The Committee, however, in
       its discretion, may provide that any Stock Options outstanding but not
       yet exercisable upon the termination of a Stock Option grantee's
       employment may become exercisable in accordance with a schedule as may be
       determined by the Committee. Such Stock Option privileges shall expire
       unless exercised or surrendered under a Stock Appreciation Right within
       such period of time after the date of termination of employment as may be
       established by the Committee, but in no event later than the expiration
       date of the Stock Option.

              (f) RETIREMENT. Upon retirement of a Stock Option grantee, Stock
       Option privileges shall apply to those shares immediately exercisable at
       the date of retirement. The Committee, however, in its discretion, may
       provide that any Stock Options outstanding but not yet exercisable upon
       the retirement of a Stock Option grantee may become exercisable in
       accordance with a schedule as may be determined by the Committee. Stock
       Option privileges shall expire unless exercised within such period of
       time as may be established by the Committee, but in no event later than
       the expiration date of the Stock Option.

              (g) DEATH. Upon the death of a Stock Option grantee, Stock Option
       privileges shall apply to those shares which were immediately exercisable
       at the time of death. The Committee, however, in its discretion, may
       provide that any Stock Options outstanding but not yet exercisable upon
       the death of a Stock Option grantee may become exercisable in accordance
       with a schedule as may be determined by the Committee. Such privileges
       shall expire unless exercised by legal representative(s) within a period
       of time as determined by the Committee, but in no event later than the
       expiration date of the Stock Option.

              (h) TERMINATION DUE TO MISCONDUCT. If a Stock Option grantee's
       employment is terminated for deliberate, willful or gross misconduct, as
       determined by the Company, all rights under the Stock Option shall expire
       upon receipt of the notice of such termination.

              (i) LIMITS ON INCENTIVE STOCK OPTIONS. Except as may otherwise be
       permitted by the Code, the Committee shall not grant to an Eligible
       Employee Incentive Stock Options that, in the aggregate, are first
       exercisable during any one calendar year to the extent that the aggregate
       fair market value of the Common Stock, at the time the Incentive Stock
       Options are granted, exceeds $100,000, or such other amount as the
       Internal Revenue Service may decide from time to time.

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6.     STOCK APPRECIATION RIGHTS

       The Committee may, in its discretion, grant a right to receive the
appreciation in the fair market value of shares of Common Stock ("Stock
Appreciation Right") either singly or in combination with an underlying Stock
Option granted hereunder or under the Prior Plans. Such Stock Appreciation
Rights shall be subject to the following terms and conditions and such other
terms and conditions as the Committee may prescribe:

              (a) TIME AND PERIOD OF GRANT. If a Stock Appreciation Right is
       granted with respect to an underlying Stock Option, it may be granted at
       the time of the Stock Option grant or at any time thereafter but prior to
       the expiration of the Stock Option grant. If a Stock Appreciation Right
       is granted with respect to an underlying Stock Option, at the time the
       Stock Appreciation Right is granted the Committee may limit the exercise
       period for such Stock Appreciation Right, before and after which period
       no Stock Appreciation Right shall attach to the underlying Stock Option.
       In no event shall the exercise period for a Stock Appreciation Right
       granted with respect to an underlying Stock Option exceed the exercise
       period for such Stock Option. If a Stock Appreciation Right is granted
       without an underlying Stock Option, the period for exercise of the Stock
       Appreciation Right shall be set by the Committee.

              (b) VALUE OF STOCK APPRECIATION RIGHT. If a Stock Appreciation
       Right is granted with respect to an underlying Stock Option, the grantee
       will be entitled to surrender the Stock Option which is then exercisable
       and receive in exchange therefor an amount equal to the excess of the
       fair market value of the Common Stock on the date the election to
       surrender is received by the Company over the Stock Option price
       multiplied by the number of shares covered by the Stock Option which is
       surrendered. If a Stock Appreciation Right is granted without an
       underlying Stock Option, the grantee will receive upon exercise of the
       Stock Appreciation Right an amount equal to the excess of the fair market
       value of the Common Stock on the date the election to surrender such
       Stock Appreciation Right is received by the Company over the fair market
       value of the Common Stock on the date of grant multiplied by the number
       of shares covered by the grant of the Stock Appreciation Right.

              (c) PAYMENT OF STOCK APPRECIATION RIGHT. Payment of a Stock
       Appreciation Right shall be in the form of shares of Common Stock, cash
       or any combination of shares and cash. The form of payment upon exercise
       of such a right shall be determined by the Committee either at the time
       of grant of the Stock Appreciation Right or at the time of exercise of
       the Stock Appreciation Right.

7.     PERFORMANCE SHARE AWARDS

       The Committee may grant awards under which payment may be made in shares
of Common Stock, cash or any combination of shares and cash if the performance
of the Company or any subsidiary, division, affiliate or joint venture of the
Company selected by the Committee during the Award Period meets certain goals
established by the Committee ("Performance Share Awards"). Such Performance
Share Awards shall be subject to the following terms and conditions and such
other terms and conditions as the Committee may prescribe:

              (a) AWARD PERIOD AND PERFORMANCE GOALS. The Committee shall
       determine and include in a Performance Share Award grant the period of
       time for which a Performance Share Award is made ( "Award Period "). The
       Committee shall also establish performance objectives ( "Performance
       Goals ") to be met by the Company, subsidiary, division or joint venture
       during the Award Period as a condition to payment of the Performance
       Share Award. The Performance Goals may include

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       earnings per share, return on stockholders' equity, return on assets, net
       income or any other financial or other measurement established by the
       Committee. The Performance Goals may include minimum and optimum
       objectives or a single set of objectives.

              (b) PAYMENT OF PERFORMANCE SHARE AWARDS. The Committee shall
       establish the method of calculating the amount of payment to be made
       under a Performance Share Award if the Performance Goals are met,
       including the fixing of a maximum payment. The Performance Share Award
       shall be expressed in terms of shares of Common Stock and referred to as
       "Performance Shares." After the completion of an Award Period, the
       performance of the Company, subsidiary, division or joint venture shall
       be measured against the Performance Goals, and the Committee shall
       determine whether all, none or any portion of a Performance Share Award
       shall be paid. The Committee, in its discretion, may elect to make
       payment in shares of Common Stock, cash or a combination of shares and
       cash. Any cash payment shall be based on the fair market value of
       Performance Shares on, or as soon as practicable prior to, the date of
       payment.

              (c) REVISION OF PERFORMANCE GOALS. At any time prior to the end of
       an Award Period, the Committee may revise the Performance Goals and the
       computation of payment if unforeseen events occur which have a
       substantial effect on the performance of the Company, subsidiary,
       division or joint venture and which, in the judgment of the Committee,
       make the application of the Performance Goals unfair unless a revision is
       made.

              (d) REQUIREMENT OF EMPLOYMENT. A grantee of a Performance Share
       Award must remain in the employ of the Company until the completion of
       the Award Period in order to be entitled to payment under the Performance
       Share Award; provided that the Committee may, in its discretion, provide
       for a full or partial payment where such an exception is deemed
       equitable.

              (e) DIVIDENDS. The Committee may, in its discretion, at the time
       of the granting of a Performance Share Award, provide that any dividends
       declared on the Common Stock during the Award Period, and which would
       have been paid with respect to Performance Shares had they been owned by
       a grantee, be (i) paid to the grantee, or (ii) accumulated for the
       benefit of the grantee and used to increase the number of Performance
       Shares of the grantee.

              (f) LIMIT ON PERFORMANCE SHARE AWARDS. Incentives granted as
       Performance Share Awards under this section and Restricted Stock Grants
       under Section 8 shall not exceed, in the aggregate, six (6) million
       shares of Common Stock (such number of shares shall be adjusted in
       accordance with Section 4(c)).

8.     RESTRICTED STOCK GRANTS

       The Committee may award shares of Common Stock to a grantee, which shares
shall be subject to the following terms and conditions and such other terms and
conditions as the Committee may prescribe ("Restricted Stock Grant"):

              (a) REQUIREMENT OF EMPLOYMENT. A grantee of a Restricted Stock
       Grant must remain in the employment of the Company during a period
       designated by the Committee ("Restriction Period") in order to retain the
       shares under the Restricted Stock Grant. If the grantee leaves the
       employment of the Company prior to the end of the Restriction Period, the
       Restricted Stock Grant shall terminate and the shares of Common Stock
       shall be returned immediately to the Company provided that the Committee
       may, at the time of the grant, provide for the employment restriction to
       lapse with respect to a portion or portions of the Restricted Stock Grant
       at different times during the Restriction Period. The Committee may, in
       its discretion, also provide for such complete or partial exceptions to
       the employment restriction as it deems equitable.

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              (b) RESTRICTIONS ON TRANSFER AND LEGEND ON STOCK CERTIFICATES.
       During the Restriction Period, the grantee may not sell, assign,
       transfer, pledge or otherwise dispose of the shares of Common Stock. Each
       certificate for shares of Common Stock issued hereunder shall contain a
       legend giving appropriate notice of the restrictions in the grant.

              (c) ESCROW AGREEMENT. The Committee may require the grantee to
       enter into an escrow agreement providing that the certificates
       representing the Restricted Stock Grant will remain in the physical
       custody of an escrow holder until all restrictions are removed or expire.

              (d) LAPSE OF RESTRICTIONS. All restrictions imposed under the
       Restricted Stock Grant shall lapse upon the expiration of the Restriction
       Period if the conditions as to employment set forth above have been met.
       The grantee shall then be entitled to have the legend removed from the
       certificates.

              (e) DIVIDENDS. The Committee shall, in its discretion, at the time
       of the Restricted Stock Grant, provide that any dividends declared on the
       Common Stock during the Restriction Period shall either be (i) paid to
       the grantee, or (ii) accumulated for the benefit of the grantee and paid
       to the grantee only after the expiration of the Restriction Period.

              (f) LIMIT ON RESTRICTED STOCK GRANT. Incentives granted as
       Restricted Stock Grants under this section and Performance Share Awards
       under Section 7 shall not exceed, in the aggregate, six (6) million
       shares of Common Stock (such number of shares shall be adjusted in
       accordance with Section 4(c)).

9.     TRANSFERABILITY

       Each Incentive Stock Option granted under the ISP shall not be
transferable other than by will or the laws of descent and distribution; each
other Incentive granted under the ISP will not be transferable or assignable by
the recipient, and may not be made subject to execution, attachment or similar
procedures, other than by will or the laws of descent and distribution or as
determined by the Committee in accordance with regulations promulgated under the
Securities Exchange Act of 1934, or any other applicable law or regulation.

10.    DISCONTINUANCE OR AMENDMENT OF THE PLAN

       The Board of Directors may discontinue the ISP at any time and may from
time to time amend or revise the terms of the ISP as permitted by applicable
statutes, except that it may not revoke or alter, in a manner unfavorable to the
grantees of any Incentives hereunder, any Incentives then outstanding, nor may
the Board amend the ISP without stockholder approval where the absence of such
approval would cause the Plan to fail to comply with Rule 16b-3 under the
Securities Exchange Act of 1934, or any other requirement of applicable law or
regulation. Unless approved by the Company's stockholders, no adjustments or
reduction of the exercise price of any outstanding Incentives shall be made by
cancellation of outstanding Incentives and the subsequent regranting of
Incentives at a lower price to the same individual. No Incentive shall be
granted under the ISP after December 31, 2003, but Incentives granted
theretofore may extend beyond that date.

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11.    NO RIGHT OF EMPLOYMENT OR PARTICIPATION

       The ISP and the Incentives granted hereunder shall not confer upon any
Eligible Employee the right to continued employment with the Company, its
subsidiaries, its affiliates or its joint ventures or affect in any way the
right of such entities to terminate the employment of an Eligible Employee at
any time and for any reason. No individual shall have a right to be granted an
Incentive, or having been granted an Incentive, to receive any future
Incentives.

12.    NO LIMITATION ON COMPENSATION

       Nothing in the ISP shall be construed to limit the right of the Company
to establish other plans or to pay compensation to its employees, in cash or
property, in a manner which is not expressly authorized under the ISP.

13.    NO IMPACT ON BENEFITS

       Except as may otherwise be specifically stated under any employee benefit
plan, policy or program, no amount payable in respect of any Incentive shall be
treated as compensation for purposes of calculating an employee's right under
any such plan, policy or program.

14.    NO CONSTRAINT ON CORPORATE ACTION

            Nothing in the ISP shall be construed (i) to limit, impair or
otherwise affect the Company's right or power to make adjustments,
reclassifications, reorganizations or changes of its capital or business
structure, or to merge or consolidate, or dissolve, liquidate, sell or transfer
all or any part of its business or assets, or (ii) except as provided in Section
10, to limit the right or power of the Company or any subsidiary to take any
action which such entity deems to be necessary or appropriate.

15.    WITHHOLDING TAXES

       The Company shall be entitled to deduct from any payment under the ISP,
regardless of the form of such payment, the amount of all applicable income and
employment taxes required by law to be withheld with respect to such payment or
may require the Eligible Employee to pay to it such tax prior to and as a
condition of the making of such payment. In accordance with any applicable
administrative guidelines it establishes, the Committee may allow an Eligible
Employee to pay the amount of taxes required by law to be withheld from an
Incentive by withholding from any payment of Common Stock due as a result of
such Incentive, or by permitting the Eligible Employee to deliver to the
Company, shares of Common Stock having a fair market value, as determined by the
Committee, equal to the amount of such required withholding taxes.

16.    GOVERNING LAW

       The ISP, and all agreements hereunder, shall be construed in accordance
with and governed by the laws of the State of New Jersey.

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                                                                   EXHIBIT 10(a)

                               SEVERANCE AGREEMENT

This Severance Agreement is by and between Professionals Group, Inc., a Michigan
corporation ("Professionals Group") and Victor T. Adamo ("Adamo").

         WITNESSETH:

         WHEREAS, pursuant to an Assumption Agreement dated August 30, 1996 (the
"Assumption Agreement"), Professionals Group assumed and agreed to perform all
of the obligations of PICOM Insurance Company pursuant to the Key Employee
Retention Plan dated July 1, 1996 (the "Plan"); and,

         WHEREAS, Adamo is the CEO of Professionals Group and a designated key
executive covered by the Plan; and,

         WHEREAS, the Compensation Committee of Professionals Group resolved on
March 2, 2000, as follows: "The two year severance arrangement now applicable to
the CEO under the Key Employee Retention Plan only in the event of a change of
control shall be amended to apply to the CEO whether or not there is a change of
control."

         WHEREAS, the actions of the Compensation Committee were adopted and
ratified by the Board of Directors of Professionals Group on March 4, 2000; and,

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         WHEREAS, this Severance Agreement is made and entered into pursuant to
the authorization of the Compensation Committee and Board of Directors as set
forth above.

         NOW THEREFORE, for valuable consideration, the receipt of which is
hereby acknowledged including, but not limited to, Adamo's continuing service as
CEO of Professionals Group, the parties agree as follows:

         1. A copy of the Plan and Assumption Agreement are attached to this
Severance Agreement as Exhibit A; and, the terms and conditions of the Plan and
Assumption Agreement are incorporated into this Severance Agreement by
reference.

         2. This Severance Agreement supplements the Plan with respect to Adamo
in the event of a Qualifying Termination where there is no Change in Control.
The Plan remains in effect with respect to Adamo in the event that there is a
Qualifying Termination following a Change in Control.

         3. For the purposes of this Severance Agreement, the following language
shall be added to section 5.1:

         5.1 NO CHANGE IN CONTROL: Adamo shall be entitled to receive from the
         Company Severance Benefits as described in Section 5.3 herein, if
         Adamo's employment with the Company shall end for any reason specified
         in Section 5.2 herein as being a Qualifying Termination. Adamo shall
         not be entitled to receive Severance Benefits if employment with the
         Company ends due to death, Disability, retirement, or to a voluntary
         termination without Good Reason - No Change of Control or due to an
         involuntary termination by the Company for Cause.

         4. For the purposes of this Severance Agreement, the following language
shall be added to section 5.2:

         5.2 NO CHANGE IN CONTROL: The occurrence of any one or more of the
         following events shall be considered a Qualifying Termination, for
         purposes of triggering the payment of Severance Benefits, as provided

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         in Section 5.1 herein:

                  (a)      A successor company fails or refuses to assume the
                           Company's obligations under this Severance Agreement;

                  (b)      The Company or any successor company breaches any of
                           the provisions of this Severance Agreement;

                  (c)      A termination of Adamo's employment with the Company
                           for reasons other then (i) death, Disability, or
                           retirement, or (ii) an involuntary termination by the
                           Company for cause; or

                  (d)      A voluntary termination of employment with the
                           Company by Adamo for Good Reason - No Change of
                           Control.

         5. For the purposes of this Severance Agreement, a new definition "Good
Reason - No Change of Control" shall be added as follows:

         "GOOD REASON - NO CHANGE IN CONTROL" means, without Adamo's express
         written consent, the occurrence of any one or more of the following:

                  (i)      The assignment of Adamo to duties inconsistent with
                           his authority, duties, responsibilities, and status
                           (including offices, titles, and reporting
                           requirements) as President and CEO of the Company, or
                           a substantial reduction or significant alteration in
                           the nature or status of Adamo's authority, duties, or
                           responsibilities from those in effect as of the date
                           of this Severance Agreement, other than an
                           insubstantial and inadvertent act that is remedied by
                           the Company promptly after receipt of notice thereof
                           given by Adamo;

                  (ii)     The Company's requiring Adamo to be based at a
                           location in excess of fifty (50) miles from Okemos,
                           Michigan;

                  (iii)    A reduction by the Company in Adamo's Base Salary as
                           in effect on the date hereof or as the same shall be

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                           increased from time to time;

                  (iv)     The failure of the Company to provide to Adamo, at a
                           level commensurate with Adamo's position, all
                           incentive compensation opportunities and employee
                           benefits that are provided to other senior executives
                           of the Company; and

                  (v)      Any purported termination by the Company of Adamo's
                           employment that is not effected pursuant to a Notice
                           of Termination satisfying the requirements of Section
                           5.7 herein, and for purposes of this Plan, no such
                           purported termination shall be effective.

         Adamo must provide the Company with written notice no later than 45
         calendar days after Adamo knows or should have known that any of the
         Good Reason - No Change in Control events as set forth in subsections
         (i) - (v) of this definition has occurred. Following the notice, the
         Company shall have 45 calendar days to rectify the circumstances
         causing the event. If the Company fails to rectify the event within the
         45 day period, or if the Company delivers to Adamo written notice
         stating that the circumstances cannot, or will not, be rectified, Adamo
         shall then have 45 days to proceed under section 5.1 and 5.2 as amended
         by this Severance Agreement. Should Adamo fail to provide the required
         notice in a timely manner, Good Reason - No Change in Control shall not
         be deemed to have occurred as a result of that event.

         Adamo's right to terminate employment for Good Reason - No Change in
         Control shall not be affected by Adamo's incapacity due to physical or
         mental illness. Except as set forth in the preceding paragraph, Adamo's
         continued employment shall not constitute consent to, or a waiver of
         rights with respect to, any circumstance constituting Good Reason - No
         Change in Control herein.

         6. In the event that Severance Benefits become payable to Adamo
pursuant to this Severance Agreement, as a condition of receiving the Severance
Benefits, Adamo agrees to provide to the Company with a signed release in the
form attached as Exhibit B to this Agreement.

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         To signify their Agreement to the terms of this Severance Agreement,
the parties have executed it as of May 4, 2000.

                                                     -------------------------
                                                     Victor T. Adamo

                                                     Professionals Group, Inc.

                                                     By:
                                                        ----------------------
                                                     William H. Woodhams, M.D.,
                                                     Chairman

                                                     And acknowledged by:

                                                     -------------------------
                                                     Annette E. Flood, Secretary

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                                    Exhibit B

                                     RELEASE

         Victor T. Adamo ("Adamo") waives, releases, and forever discharges
         Professionals Group, Inc.(the "Company") and its direct or indirect
         parents, subsidiaries, affiliates and related entities, any
         partnerships, joint ventures or other entities involving or related to
         the Company or its affiliates, and all present or former employees,
         officer, agents, directors, successors, assigns and attorneys of any of
         these corporations, persons or entities (all collectively referred to
         herein as the "Releasees"); from any and all claims, charges, suits,
         causes of action, demands, expenses and compensation whatsoever, known
         or unknown, direct or indirect, on account of or growing out of Adamo's
         employment with and termination from the Company, or relationship or
         termination of such relationship with any of the Releasees; or arising
         out of related events occurring through the date that this Release is
         executed. This includes, but is not limited to, claims for breach of
         any employment contract, handbook or manual; any express or implied
         contract; wrongful discharge; any tort; continued employment; loss of
         wages or benefits; attorney fees; discrimination arising under any
         federal, state, or local civil rights or antidiscrimination statute,
         including specifically any claims Adamo may have under the federal Age
         Discrimination in Employment Act, as amended, 29 USC ss.ss. 621, et
         seq; attorney fees; emotional distress, harassment, defamation,
         slander, and all other types of claims or causes of action whatsoever
         arising under any other state or federal statute or common law of the
         United States.

         Adamo does not waive or release any rights or claims (i) that may arise
         under the federal Age Discrimination in Employment Act, as amended,
         after the date this Release is executed by Adamo; and (ii) that relate
         to receipt of Severance Benefits payable to Adamo in connection with
         Adamo's termination of employment with the Company.

6

<PAGE>   7

         Adamo acknowledges that he received this Agreement on             ,
         2   , that he was advised that this was the company's FINAL OFFER and
         that he has been given adequate time to consider the terms of this
         Agreement and consult with an attorney if he desires. The Company
         agrees that this Agreement will remain available until the close of
         business until the earlier of: (1) his rejection of this Agreement; or
         (2) twenty-two calendar days following his receipt of this Agreement.
         At that time, if Adamo has not yet executed the Agreement, the
         Agreement will be revoked. If Adamo executes this Agreement, he shall
         have no fewer than eight calendar days following his execution of the
         Agreement to revoke it. Any revocation shall be made in writing and
         shall be received by the Company's Corporate Counsel, at 2600
         Professionals Drive, Box 150, Okemos, Michigan, 48805-0150 on or before
         4:30 p.m. on the eighth calendar day after Adamo executed it. This
         Agreement shall not become effective or enforceable until the
         expiration of the revocation period.

         ----------------------                      -------------------
         Date Agreement Accepted                     Victor T. Adamo

         --------------------                        -------------------
         Date Agreement Accepted                     By:  Professionals Group,
                                                     Inc.

7

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