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                                                                    EXHIBIT 10.1


                      PRAECIS PHARMACEUTICALS INCORPORATED

                   SECOND AMENDED AND RESTATED 1995 STOCK PLAN


1.       PURPOSE.  This Second Amended and Restated 1995 Stock Plan
         (the "Plan") is intended to benefit and provide incentives:

         (a)      to the employees of PRAECIS PHARMACEUTICALS INCORPORATED (the
                  "Company"), its parent (if any) and any present or future
                  subsidiaries of the Company (collectively, "Related
                  Corporations"), by providing them with opportunities to
                  purchase stock in the Company pursuant to options granted
                  hereunder which qualify as "incentive stock options" ("ISO" or
                  "ISOs") under Section 422(b) of the Internal Revenue Code of
                  1986, as amended (the "Code");

         (b)      to employees, directors and consultants of the Company and
                  Related Corporations by providing them with opportunities to
                  purchase stock in the Company pursuant to options granted
                  hereunder which do not qualify as ISOs ("Non-Qualified Option"
                  or "Non-Qualified Options"); and

         (c)      to employees, directors and consultants of the Company and
                  Related Corporations by providing them with awards, or
                  opportunities to make direct purchases, of stock in the
                  Company ("Awards").

                  Both ISOs and Non-Qualified Options are referred to
hereinafter individually as an "Option" and collectively as "Options." Options
and Awards are referred to hereinafter collectively as "Stock Rights." As used
herein, the terms "parent" and "subsidiary" mean "parent corporation" and
"subsidiary corporation," respectively, as those terms are defined in Section
424 of the Code.

2. ADMINISTRATION OF THE PLAN.

                  A.       BOARD OR COMMITTEE ADMINISTRATION. The Plan shall be
                           administered by a Committee of not less than two (2)
                           persons, each of whom shall be a "Non-Employee
                           Director" within the meaning of Rule 16b-3(b)(3)(i)
                           promulgated under the Securities Exchange Act of
                           1934, as amended (the "Exchange Act") and an "outside
                           director" within

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                           the meaning of Section 162(m) of the Code. The
                           members of the Committee shall be appointed by the
                           Company's Board of Directors (the "Board") and shall
                           serve at the pleasure of the Board. If no Committee
                           has been appointed to administer the Plan, the
                           functions of the Committee specified in the Plan
                           shall be carried out by the Board, except that at any
                           time after a registration of any of the Company's
                           stock under the Exchange Act or the Company
                           otherwise becomes subject to the reporting
                           requirements of the Exchange Act, administration by a
                           Committee is required. Subject to the terms of the
                           Plan, the Committee shall have the authority to:

                           (i)           determine the employees of the Company
                                         and Related Corporations (from among
                                         the class of employees eligible under
                                         paragraph 3 to receive ISOs) to whom
                                         ISOs may be granted, and to determine
                                         (from among the class of individuals
                                         and entities eligible under paragraph 3
                                         to receive Non-Qualified Options and
                                         Awards) to whom Non-Qualified Options
                                         and Awards may be granted;

                           (ii)          determine the time or times at which
                                         Options or Awards may be granted;

                           (iii)         determine the option price of shares
                                         subject to each Option, which price
                                         shall not be less than the minimum
                                         price specified in paragraph 6, and the
                                         purchase price (if any) of shares
                                         subject to each Award;

                           (iv)          determine whether each Option granted
                                         shall be an ISO or a Non-Qualified
                                         Option;

                           (v)           determine (subject to paragraph 7) the
                                         time or times when each Option shall
                                         become exercisable and the duration of
                                         the exercise period;

                           (vi)          determine whether restrictions such as
                                         repurchase rights and other vesting
                                         restrictions are to be imposed on
                                         shares subject to Options and Awards
                                         and the nature of such restrictions, if
                                         any, and


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                                         other terms and conditions of Options
                                         and Awards not inconsistent with the
                                         Plan; and

                           (vii)         interpret the Plan and prescribe and
                                         rescind rules and regulations relating
                                         to it.

                           If the Committee determines to issue a Non-Qualified
         Option, it shall designate the Non-Qualified Option as such upon grant
         and in the agreement governing such Non-Qualified Option. The
         interpretation and construction by the Committee of any provisions of
         the Plan or of any Stock Right granted under it shall be final unless
         otherwise determined by the Board. The Committee may from time to time
         adopt such rules and regulations for carrying out the Plan as it may
         deem best. No member of the Board or the Committee shall be liable for
         any action or determination made in good faith with respect to the Plan
         or any Stock Right granted under the Plan.

                  B.       COMMITTEE ACTIONS.  The Committee may select one
                           of its members as its chairman, and shall hold
                           meetings at such time and place as it may deter
                           mine.  Acts by a majority of the Committee, or
                           acts reduced to or approved in writing by a
                           majority of the members of the Committee, shall
                           be the valid acts of the Committee.  All references
                           in this Plan to the Committee shall mean the Board
                           if no Committee has been appointed.

3.       ELIGIBLE EMPLOYEES AND OTHERS.  ISOs may be granted to any
         employee (including an employee who serves as an officer
         or director) of the Company or any Related Corporation.
         Non-Qualified Options and Awards may be granted to any
         employee (including an employee who serves as an officer
         or director), director or consultant (including a consultant
         who also serves as a director) of the Company or any
         Related Corporation.  The Committee may take into
         consideration a recipient's individual circumstances in
         determining whether to grant a Stock Right.  No participant
         in the Plan shall be granted Stock Rights which in
         the aggregate exceed 50% of the total number of shares of
         common stock, par value $.01 per share (the "Common
         Stock"), of the Company authorized to be issued with
         respect to such Stock Rights pursuant to the Plan.  The
         granting of any Stock Right to any individual or entity
         shall neither entitle that individual or entity to, nor
         disqualify him from, participation in any other grant of
         Stock Rights.


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4.       STOCK.  The stock subject to Options and Awards shall be
         authorized but unissued shares of Common Stock or shares
         of Common Stock reacquired by the Company in any manner.
         The aggregate number of shares which may be issued pursuant
         to the Plan is 11,375,000, subject to adjustment as
         provided in paragraph 13.  Any such shares may be issued
         pursuant to ISOs, Non-Qualified Options or Awards, so long
         as the number of shares so issued does not exceed such
         number, as adjusted.  If any Option granted under the Plan
         shall expire or terminate for any reason without having
         been exercised in full or shall cease for any reason to be
         exercisable in whole or in part, or if the Company shall
         reacquire any unvested shares issued pursuant to Awards,
         the unpurchased shares subject to such Options and any
         unvested shares so reacquired by the Company shall again
         be available for grants of Stock Rights under the Plan.

5.       GRANTING OF STOCK RIGHTS.  Stock Rights may be granted
         under the Plan at any time on or after January 5, 1995 and
         prior to the close of business on January 5, 2005.  The
         date of grant of a Stock Right under the Plan will be the
         date specified by the Committee at the time it grants the
         Stock Right; provided, however, that such date shall not
         be prior to the date on which the Committee acts to approve
         the grant. The Committee shall have the right, with
         the consent of the optionee, to convert an ISO granted
         under the Plan to a Non-Qualified Option pursuant to
         paragraph 16.

6.       MINIMUM OPTION PRICE; ISO LIMITATIONS.

                  A.       EXERCISE PRICE FOR NON-QUALIFIED OPTIONS. The
                           exercise price per share specified in the agreement
                           relating to each Non-Qualified Option granted under
                           the Plan shall in no event be less than the par value
                           per share of Common Stock as of the date of grant.

                  B.       EXERCISE PRICE FOR ISOs.  The exercise price per
                           share of Common Stock specified in the agreement
                           relating to each ISO granted under the Plan
                           shall not be less than the fair market value per
                           share of Common Stock on the date of such grant.
                           In the case of an ISO to be granted to an employee
                           owning stock possessing more than ten percent (10%)
                           of the total combined voting power of all classes of
                           stock of the Company or any Related Corporation, the
                           price per share specified in the agreement relating
                           to such ISO shall


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                           not be less than one hundred ten percent (110%) of
                           the fair market value per share of Common Stock on
                           the date of such grant.

                  C.       $100,000 ANNUAL LIMITATION ON ISOs.  Each eligible
                           employee may be granted ISOs only to the
                           extent that, in the aggregate under this Plan
                           and all incentive stock option plans of the
                           Company and any Related Corporation, such ISOs
                           do not become exercisable for the first time by
                           such employee during any calendar year in a
                           manner which would entitle the employee to purchase
                           more than $100,000 in fair market value (determined
                           at the time the ISOs were granted) of Common Stock
                           in that year. Any options granted to an employee in
                           excess of such amount will be granted as
                           Non-Qualified Options.

                  D.       DETERMINATION OF FAIR MARKET VALUE.  If, at the
                           time an Option is granted under the Plan, the
                           Company's Common Stock is publicly traded, "fair
                           market value" shall be determined as of the last
                           business day for which the prices or quotes
                           referred to in this sentence are available prior
                           to the date such Option is granted and shall
                           mean (i) the average (on that date) of the high
                           and low prices of the Common Stock on the principal
                           national securities exchange on which the
                           Common Stock is traded, if the Common Stock is
                           then traded on a national securities exchange;
                           or (ii) the last reported sale price (on that
                           date) of the Common Stock on the Nasdaq National
                           Market, if the Common Stock is not then traded
                           on a national securities exchange; or (iii) the
                           closing bid price (or average bid prices) last
                           quoted (on that date) by an established quotation
                           service for over-the-counter securities, if
                           the Common Stock is not then listed on the
                           Nasdaq National Market.  However, if the Common
                           Stock is not publicly traded at the time an
                           Option is granted under the Plan, "fair market
                           value" shall be deemed to be the fair value of
                           the Common Stock as determined by the Committee
                           after taking into consideration all factors
                           which it deems appropriate, including, without
                           limitation, recent sale and offer prices of the
                           Common Stock in private transactions negotiated
                           at arm's length.


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7.       OPTION DURATION. Subject to earlier termination as provided in
         paragraphs 9 and 10, each Option shall expire on the date specified by
         the Committee, but not more than (i) ten years from the date of grant
         in the case of ISOs generally (to the extent such Option is intended to
         be an ISO), and (ii) five years from the date of grant in the case of
         ISOs granted to an employee owning stock possessing more than ten
         percent (10%) of the total combined voting power of all classes of
         stock of the Company or any Related Corporation. Subject to earlier
         termination as provided in paragraphs 9 and 10, the term of each ISO
         shall be the term set forth in the original instrument granting such
         ISO, except with respect to any part of such ISO that is converted into
         a Non-Qualified Option pursuant to paragraph 16.

8.       EXERCISE OF OPTION. Subject to the provisions of paragraphs 9 through
         12, each Option granted under the Plan shall be exercisable as follows:

                  A.       VESTING.  The Option (or any portion thereof)
                           shall be fully exercisable on the date of grant
                           or shall become exercisable thereafter in such
                           installments as the Committee may specify.

                  B.       FULL VESTING OF INSTALLMENTS.  Once an installment
                           becomes exercisable, it shall remain exercisable
                           until expiration or termination of the Option,
                           unless otherwise specified by the Committee.

                  C.       PARTIAL EXERCISE.  Each Option or installment
                           may be exercised at any time or from time to
                           time, in whole or in part, for up to the total
                           number of shares with respect to which it is
                           then exercisable.

                  D.       ACCELERATION OF VESTING. The Committee shall have the
                           right to accelerate the date of exercise of any
                           installment of any Option; provided, that the
                           Committee shall not, without the consent of an
                           optionee, accelerate the exercise date of any
                           installment of any Option granted to any employee as
                           an ISO (and not previously converted into a
                           Non-Qualified Option pursuant to paragraph 16) if
                           such acceleration would violate the annual vesting
                           limitation contained in Section 422(d) of the Code,
                           as described in paragraph 6(C).


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9.       TERMINATION OF EMPLOYMENT. If an ISO optionee ceases to be employed by
         the Company and all Related Corporations, except as provided in
         paragraph 10, no further installments of his ISOs shall become
         exercisable (unless other wise approved by the Committee), and his ISOs
         which are exercisable on the date of termination of his employment
         shall terminate after the passage of three months from the date of
         termination of his employment, but in no event later than on their
         specified expiration dates, except (i) in the case of termination for
         "Misconduct," as defined in the instrument granting such ISOs, in which
         case such ISOs shall terminate automatically on the date of such
         termination, and (ii) to the extent that such ISOs (or unexercised
         installments thereof) have been converted into Non-Qualified Options
         pursuant to paragraph 16. Employment shall be considered as continuing
         uninterrupted during any bona fide leave of absence (such as those
         attributable to illness, military obligations or governmental service);
         provided, that the period of such leave does not exceed three months
         or, if longer, any period during which such optionee's right to
         reemployment is guaranteed by statute. A bona fide leave of absence
         with the written approval of the Committee shall not be considered an
         interruption of employment under the Plan, provided, that such written
         approval contractually obligates the Company or any Related Corporation
         to continue the employment of the optionee after the approved period of
         absence. ISOs granted under the Plan shall not be affected by any
         change of employment within or among the Company and Related
         Corporations, so long as the optionee continues to be an employee of
         the Company or any Related Corporation. Nothing in the Plan shall be
         deemed to give any grantee of any Stock Right the right to be retained
         in employment or other service by the Company or any Related
         Corporation for any period of time.

10.      DEATH; DISABILITY.

                  A.       DEATH. If an ISO optionee ceases to be employed by
                           the Company and all Related Corporations by reason of
                           his death, any ISO of his may be exercised, to the
                           extent of the number of shares with respect to which
                           he could have exercised it on the date of his death,
                           by his estate, personal representative or beneficiary
                           who has acquired the ISO by will or by the laws of
                           descent and distribution, at any time prior to the
                           earlier of the specified expiration date of the ISO
                           or 180 days from the date of the optionee's


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                           death or such longer period not in excess of one
                           year as the Committee shall determine.

                  B.       DISABILITY. If an ISO optionee ceases to be employed
                           by the Company and all Related Corporations by reason
                           of his disability, he shall have the right to
                           exercise any ISO held by him on the date of
                           termination of employment, to the extent of the
                           number of shares with respect to which he could have
                           exercised it on that date, at any time prior to the
                           earlier of the specified expiration date of the ISO
                           or 180 days from the date of the termination of the
                           optionee's employment or such longer period not in
                           excess of one year as the Committee shall determine.
                           For the purposes of the Plan, the term "disability"
                           shall mean "permanent and total disability" as
                           defined in Section 22(e)(3) of the Code or successor
                           statute.

11.      ASSIGNABILITY. No Option shall be assignable or transferable by the
         optionee except by will or by the laws of descent and distribution or,
         in the sole discretion of the Committee at the time of the proposed
         assignment or transfer, pursuant to a qualified domestic relations
         order as defined under the Code or Title I of the Employee Retirement
         Income Security Act (or the rules thereunder), or as the Committee, in
         its sole discretion, shall otherwise permit. The Option shall be
         exercisable during the lifetime of the optionee only by such optionee
         or his guardian or legal representative, or by an assignee or
         transferee if the Option has been assigned or transferred in compliance
         with the immediately preceding sentence. Notwithstanding the
         foregoing, to the extent the instrument evidencing any Non-Qualified
         Option so provides, and subject to the conditions that the Committee
         may prescribe, an optionee may, upon providing written notice to the
         President of the Company, elect to transfer the Options granted to such
         optionee pursuant to such instrument, without consideration therefor.
         The terms of such Option shall be binding upon any recipient of such
         Option.

12.      TERMS AND CONDITIONS OF OPTIONS. Options shall be evidenced by
         instruments (which need not be identical) in such forms as the
         Committee may from time to time approve. Such instruments shall conform
         to the terms and conditions set forth in paragraphs 6 through 11 hereof
         and may contain such other provisions as the Committee deems advisable
         which are not inconsistent with the Plan, including restrictions
         applicable to shares of Common Stock issuable


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         upon exercise of Options (including, without limitation, rights of
         repurchase by the Company and, in the event of an underwritten public
         offering of the Company's securities, restrictions on any sale or
         distribution by the optionee of any of the Company's common equity for
         a period of time as the underwriters in such public offering shall
         determine). In granting any Non-Qualified Option, the Committee may
         specify that such Non-Qualified Option shall be subject to the
         restrictions set forth herein with respect to ISOs, or to such other
         termination, cancellation and other provisions not inconsistent with
         the Plan as the Committee may determine. The Committee may from time to
         time confer authority and responsibility on one or more of its own
         members or one or more officers of the Company to execute and deliver
         such instruments. The proper officers of the Company are authorized and
         directed to take any and all action necessary or advisable from time to
         time to carry out the terms of such instruments.

13.      ADJUSTMENTS. Upon the occurrence of any of the following events, an
         optionee's rights with respect to Options granted to him hereunder
         shall be adjusted as and to the extent hereinafter required, unless
         otherwise specifically provided in the written agreement between the
         optionee and the Company relating to such Option:

                  A.       STOCK DIVIDENDS AND STOCK SPLITS.  If the shares
                           of Common Stock shall be subdivided or combined
                           into a greater or smaller number of shares or if
                           the Company shall issue any shares of Common
                           Stock as a stock dividend on its outstanding
                           Common Stock, the number of shares of Common
                           Stock deliverable upon the exercise of Options
                           shall be appropriately increased or decreased
                           proportionately and appropriate adjustments
                           shall be made in the purchase price per share to
                           reflect such subdivision, combination or stock
                           dividend.

                  B.       CONSOLIDATIONS OR MERGERS. If the Company is to be
                           consolidated with or acquired by another entity in a
                           merger, sale of all or substantially all of the
                           Company's assets or otherwise (an "Acquisition"), the
                           committee or the board of directors of any entity
                           assuming the obligations of the Company hereunder
                           (the "Successor Board"), shall, as to outstanding
                           Options, either (i) make appropriate provision for
                           the continuation of such Options by substitution on
                           an equitable basis for the shares then subject


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                           to such Options the consideration payable with
                           respect to the outstanding shares of Common Stock in
                           connection with the Acquisition; (ii) upon written
                           notice to the optionees, provide that all Options
                           must be exercised, to the extent then exercisable
                           (or in the discretion of the Committee or the
                           Successor Board, also provide that all unvested
                           Options shall be, or become at the time which the
                           Committee shall determine, immediately exercisable),
                           within a specified number of days of the date of such
                           notice, at the end of which period the Options shall
                           terminate; or (iii) terminate all Options in exchange
                           for a cash payment or other consideration equal to
                           the excess of the fair market value of the shares
                           subject to such Options (to the extent then
                           exercisable, or in the discretion of the Committee or
                           the Successor Board, whether or not then exercisable)
                           over the exercise price thereof.

                  C.       RECAPITALIZATION OR REORGANIZATION. In the event of a
                           recapitalization or reorganization of the Company
                           (other than a transaction described in subparagraph B
                           above) pursuant to which securities of the Company or
                           of another corporation are issued with respect to the
                           outstanding shares of Common Stock, an optionee upon
                           exercising an Option shall be entitled to receive for
                           the purchase price paid upon such exercise, the
                           securities he would have received if he had exercised
                           his Option immediately prior to such recapitalization
                           or reorganization.

                  D.       MODIFICATION OF ISOs. Notwithstanding the foregoing,
                           any adjustments made pursuant to subparagraphs A, B
                           or C with respect to ISOs shall be made only after
                           the Committee, after consulting with counsel for the
                           Company, determines whether such adjustments would
                           constitute a "modification" of such ISOs (as that
                           term is defined in Section 424 of the Code) or would
                           cause any adverse tax consequences for the holders of
                           such ISOs. If the Committee determines that such
                           adjustments made with respect to ISOs would
                           constitute a modification of such ISOs, it may
                           refrain from making such adjustments.

                  E.       DISSOLUTION OR LIQUIDATION. In the event of the
                           proposed dissolution or liquidation of the Com-


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                           pany, each Option will terminate immediately prior to
                           the consummation of such proposed action or at such
                           other time and subject to such other conditions as
                           shall be determined by the Committee.

                  F.       ISSUANCES OF SECURITIES. Except as expressly provided
                           herein, no issuance by the Company of shares of stock
                           of any class, or securities convertible into shares
                           of stock of any class, shall affect, and no
                           adjustment by reason thereof shall be made with
                           respect to, the number or price of shares subject to
                           Options. No adjustments shall be made for dividends
                           paid in cash or in property other than securities of
                           the Company.

                  G.       FRACTIONAL SHARES.  No fractional shares shall
                           be issued under the Plan and the optionee shall
                           receive from the Company cash in lieu of such
                           fractional shares.

                  H.       ADJUSTMENTS. Upon the happening of any of the events
                           described in subparagraphs A, B or C above, the class
                           and aggregate number of shares set forth in paragraph
                           4 hereof that are subject to Stock Rights which
                           previously have been or subsequently may be granted
                           under the Plan shall also be appropriately adjusted
                           to reflect the events described in such
                           subparagraphs. If changes in the capitalization of
                           the Company shall occur other than those referred to
                           above in this Paragraph 13, the Committee shall make
                           such adjustments, if any, in the number of shares
                           covered by each Option and in the per share purchase
                           price as the Committee in its discretion may consider
                           appropriate. The Committee or, if applicable, the
                           Successor Board, shall determine the specific
                           adjustments to be made under this paragraph 13 and
                           its determination shall be conclusive.

                  If any person or entity owning restricted Common Stock
obtained by exercise of a Stock Right made hereunder receives shares or
securities or cash in connection with a corporate transaction described in
subparagraphs A, B or C above as a result of owning such restricted Common
Stock, such shares or securities or cash shall be subject to all of the
conditions and restrictions applicable to the restricted Common Stock with
respect to which such shares or securities or cash


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were issued, unless otherwise determined by the Committee or the Successor
Board.

14.      MEANS OF EXERCISING OPTIONS. An Option (or any part or installment
         thereof) shall be exercised by giving written notice to the Company at
         its principal executive office or to the transfer agent as the Company
         shall designate. Such notice shall identify the Option being exercised
         and specify the number of shares as to which such Option is being
         exercised, accompanied by full payment of the purchase price therefor
         (a) in United States dollars in cash or by check, (b) at the discretion
         of the Committee, by delivery of shares of Common Stock (the value of
         which for this purpose shall be determined by the Committee), (c) at
         the discretion of the Committee, by delivery of the grantee's personal
         recourse note bearing interest payable not less than annually at no
         less than 100% of the lowest applicable Federal rate, as defined in
         Section 1274(d) of the Code or (d) subject to clauses (b) and (c), by
         any combination of (a), (b) or (c) above. In connection with any
         payment pursuant to clause (c) above, the Committee may require the
         optionee to concurrently execute and deliver to the Company a pledge
         agreement in a form reasonably satisfactory to the Company, together
         with a stock certificate or certificates representing shares of the
         Company's Common Stock (having an aggregate fair market value, as
         determined by the Committee), equal as of the date of exercise to at
         least the value of the principal amount of the note), duly endorsed or
         accompanied by a stock power or powers duly endorsed, to secure the
         optionee's obligations under such personal recourse note. The holder of
         an Option shall not have the rights of a shareholder with respect to
         the shares covered by his Option until the date of issuance of a stock
         certificate to him for such shares. Except as expressly provided above
         in paragraph 13 with respect to changes in capitalization and stock
         dividends, no adjustment shall be made for dividends or similar rights
         for which the record date is before the date such stock certificate is
         issued.

15.      TERM AND AMENDMENT OF PLAN.  The Company's 1995 Stock Plan
         was originally adopted on January 5, 1995.  The Plan as
         currently in effect was adopted by the Board on February 2, 2000,
         approved by the stockholders of the Company on February 28, 2000,
         and shall be effective automatically upon consummation of the
         Company's initial public offering. The Plan shall expire at the end
         of the day on January 5, 2005 (except as to Stock Rights outstanding
         on that date).  The Board may terminate or amend the Plan in any
         respect at any time; provided, that no such amendment or termination
         shall adversely affect any Plan participant's rights under
         any Stock Right previously granted, without such participant's written
         consent. If the scope of any amendment is


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         such as to require stockholder approval in order to comply with Section
         162(m) of the Code or any other law, regulation or stock exchange
         requirement, then such amendment shall not be effective unless and
         until such stockholder approval is obtained.

16.      CONVERSION OF ISOs INTO NON-QUALIFIED OPTIONS; TERMINATION OF ISOs. The
         Committee, at the written request of any optionee, may in its
         discretion, take such actions as may be necessary to convert such
         optionee's ISOs (or any installments or portions of installments
         thereof) that have not been exercised on the date of conversion into
         Non-Qualified Options at any time prior to the expiration of such ISOs,
         regardless of whether the optionee is an employee of the Company or a
         Related Corporation at the time of such conversion. Such actions may
         include, but not be limited to, extending the exercise period or
         reducing the exercise price of the appropriate installments of such
         ISOs. At the time of such conversion, the Committee (with the consent
         of the optionee) may impose such conditions on the exercise of the
         resulting Non-Qualified Options as the Committee in its discretion may
         determine; provided, that such conditions shall not be inconsistent
         with this Plan. Nothing in the Plan shall be deemed to give any
         optionee the right to have such optionee's ISOs converted into
         Non-Qualified Options, and no such conversion shall occur until and
         unless the Committee takes appropriate action. The Committee, with the
         consent of the optionee, may also terminate any portion of any ISO that
         has not been exercised at the time of such conversion.

17.      GOVERNMENTAL REGULATION. The Company's obligation to sell and deliver
         shares of the Common Stock under this Plan is subject to the approval
         of any governmental authority required in connection with the
         authorization, issuance or sale of such shares.

18.      TAX WITHHOLDING. Upon the exercise of a Non-Qualified Option, the grant
         of an Award or the making of a purchase of Common Stock for less than
         its fair market value pursuant to an Award, the making of a
         Disqualifying Disposition (as defined in paragraph 19) or the vesting
         of Restricted Stock (as defined in paragraph 20), the Company, in
         accordance with Section 3402(a) of the Code, may require the optionee
         or Award recipient to pay withholding taxes in respect of the amount
         that is considered compensation required to be included in such
         person's gross income. The Committee, in its discretion, may condition
         (i) the exercise of an Option, (ii) the grant of an Award, (iii)


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<PAGE>

         the making of a purchase of Common Stock for less than its fair market
         value pursuant to an Award or (iv) the vesting of Restricted Stock on
         the grantee's payment of such withholding taxes. The Committee shall
         have the sole discretion to determine the form in which payment of such
         withholding taxes will be made (I.E., cash, securities or a combination
         thereof).

19.      NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION.  Each
         employee who receives an ISO must agree to notify the
         Company in writing immediately after the employee makes a
         Disqualifying Disposition of any Common Stock acquired
         pursuant to the exercise of an ISO.  A Disqualifying
         Disposition is any disposition (including any sale) of
         such Common Stock before the later of (a) two years after
         the date the employee was granted the ISO or (b) one year
         after the date the employee acquired Common Stock by
         exercising the ISO.  If the employee has died before such
         stock is sold, these holding period requirements do not
         apply and no Disqualifying Disposition can occur thereafter.

20.      PROVISIONS RELATED TO RESTRICTED STOCK AND OTHER AWARDS.

                  A.       Awards of shares of Common Stock may be granted
                           either alone, in addition to or in tandem with other
                           awards granted under the Plan or cash awards made
                           outside the Plan, and such shares may be subject to
                           repurchase by the Company upon such terms and
                           conditions as the Committee may determine (such
                           shares subject to such repurchase being referred to
                           as "Restricted Stock"). The Committee shall determine
                           the eligible persons to whom, and the time or times
                           at which, Awards will be made, the number of shares
                           to be awarded, the price (if any) to be paid by the
                           Award recipient, in the case of Restricted Stock, the
                           time or times within which such shares of Restricted
                           Stock may be subject to forfeiture and all other
                           terms and conditions of any such Award. The Committee
                           may condition an Award or the vesting of Restricted
                           Stock upon the attainment of specified performance
                           goals or such other factors as the Committee may
                           determine in its sole discretion. The terms and
                           conditions of Awards need not be the same for each
                           recipient.

                  B.       The prospective recipient of an Award shall not
                           have any rights with respect to such Award,


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<PAGE>

                           unless and until such recipient has executed an
                           agreement evidencing the Award and has delivered a
                           fully executed copy thereof to the Company, and has
                           otherwise complied with the applicable terms and
                           conditions of such Award.

                           (i)           The consideration for shares issued
                                         pursuant to an Award shall be equal to
                                         or greater than their par value.

                           (ii)          Awards must be accepted within a period
                                         of sixty (60) days (or such shorter
                                         period as the Committee may specify at
                                         grant) after the Award date, by
                                         executing an Award agreement and
                                         paying whatever price (if any) is
                                         required under the Award.

                           (iii)         A stock certificate in respect of
                                         shares of Common Stock which are the
                                         subject of an Award shall be issued in
                                         the name of the participant receiving
                                         such Award, and shall bear an
                                         appropriate legend referring to the
                                         terms, conditions and restrictions
                                         applicable to such Award.

                           (iv)          The Committee may require that the
                                         stock certificates evidencing
                                         shares of Restricted Stock be held
                                         in custody by the Company until the
                                         restrictions thereon shall have
                                         lapsed, and that, as a condition of
                                         any Restricted Stock Award, the
                                         participant shall have delivered a
                                         stock power, endorsed in blank,
                                         relating to the shares of
                                         Restricted Stock covered by such
                                         Award.

                  C.       Awards of shares of Restricted Stock under the Plan
                           shall be subject to the following restrictions and
                           conditions (in addition to other restrictions and
                           conditions set forth in the Award agreement with
                           respect to such shares not inconsistent with this
                           Plan which the Committee shall determine in its sole
                           discretion):

                           (i)           Subject to the provisions of the Plan
                                         and the Award agreement, during a
                                         period set by the Committee commencing
                                         with the date of such Award (the
                                         "Restricted


                                       15
<PAGE>

                                         Period"), the participant shall not be
                                         permitted to sell, transfer, pledge or
                                         assign shares of Restricted Stock
                                         issued pursuant to an Award. The
                                         Committee, in its sole discretion, may
                                         provide for the lapse of such
                                         restrictions in installments and may
                                         accelerate or waive such restrictions
                                         in whole or in part, based on service,
                                         performance or such other factors or
                                         criteria as the Committee may
                                         determine, in its sole discretion. The
                                         Award agreement may contain other
                                         restrictions and conditions not
                                         inconsistent with the Plan as the
                                         Committee shall deem appropriate,
                                         including without limitation, rights
                                         of repurchase by the Company and, in
                                         the event of an underwritten public
                                         offering of the Company's securities,
                                         restrictions on any sale or
                                         distribution by the Award recipient of
                                         any of the Company's common equity for
                                         a period of time as the underwriters
                                         in such public offering shall
                                         determine.

                           (ii)          Except as provided herein, the
                                         recipient shall have, with respect to
                                         shares of Restricted Stock issued
                                         pursuant to an Award, all of the rights
                                         of a stock holder of the Company,
                                         including the right to vote the shares,
                                         and the right to receive any cash
                                         dividends. The Committee may, in its
                                         sole discretion, at the time of the
                                         grant of an Award of Restricted Stock,
                                         permit or require the payment of cash
                                         dividends with respect to such
                                         Restricted Stock to be deferred and, if
                                         the Committee so determines,
                                         reinvested, in additional shares of
                                         Restricted Stock to the extent shares
                                         are available under the Plan, or other
                                         wise reinvested. Stock dividends issued
                                         with respect to Restricted Stock shall
                                         be treated as additional shares of
                                         Restricted Stock that are subject to
                                         the same restrictions and other terms
                                         and conditions that apply to the shares
                                         with respect to which such dividends
                                         are issued.


                                       16
<PAGE>

                           (iii)         Subject to the applicable provisions of
                                         the Award agreement, if and when the
                                         Restricted Period expires without a
                                         prior forfeiture of the Restricted
                                         Stock subject to such Restricted
                                         Period, certificates for an appropriate
                                         number of unrestricted shares (without
                                         any legend referred to in subparagraph
                                         (iii) of subsection B of Section 20)
                                         shall be delivered to the participant
                                         promptly upon the surrender and
                                         cancellation of the previously issued
                                         certificate(s) representing such
                                         shares.

21.      GOVERNING LAW; CONSTRUCTION. The validity and construction of the Plan
         and the instruments evidencing Stock Rights shall be governed by the
         laws of the Commonwealth of Massachusetts, or the laws of any
         jurisdiction in which the Company or its successors in interest may be
         organized. In construing this Plan, the singular shall include the
         plural and the masculine gender shall include the feminine and neuter,
         unless the contest otherwise requires.


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