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                                                                     Exhibit 4.1


                                HADCO CORPORATION

                                 1998 STOCK PLAN

                             AS AMENDED AND RESTATED

                                  MARCH 3, 1999

         1. PURPOSE. The purpose of the Hadco Corporation 1998 Stock Plan (the
"Plan") is to encourage valuable employees of Hadco Corporation (the "Company")
and of any present or future parent or subsidiary of the Company (collectively,
"Related Corporations") and other individuals who render services to the Company
or a Related Corporation, by providing opportunities to participate in the
ownership of the Company and its future growth through (a) the grant of options
("Non-Qualified Options") which do not qualify as "incentive stock options"
("ISOs") under Section 422(b) of the Internal Revenue Code of 1986, as amended
(the "Code"); (b) awards of stock in the Company ("Awards"); and (c)
opportunities to make direct purchases of stock in the Company ("Purchases").
Non-Qualified Options are referred to hereafter individually as an "Option" and
collectively as "Options." Options, Awards and authorizations to make Purchases
are referred to hereafter 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 the Board of Directors of the Company (the "Board") or, subject
to paragraph 2(D) relating to compliance with Section 162(m) of the Code, by a
committee appointed by the Board (the "Committee"). Hereinafter, all references
in this Plan to the "Committee" shall mean the Board if no Committee has been
appointed. Subject to ratification of the grant or authorization of each Stock
Right by the Board (if so required by applicable state law), and subject to the
terms of the Plan, the Committee shall have the authority to (i) determine to
whom (from among the class of individuals eligible under paragraph 3 to receive
Stock Rights) Options, Awards and authorizations to make Purchases shall be
granted (each such individual who receives a Stock Right hereunder being
referred to as a "Participant"); (ii) determine the time or times at which
Options, Awards and authorizations to make Purchases shall be granted; (iii)
determine the purchase price of shares subject to each Option or Purchase, which
price shall not be less than the minimum price specified in paragraph 6; (iv)
determine (subject to paragraph 7) the time or times when each Option or
Purchase shall become exercisable and the duration of the exercise period; (v)
extend the period during which outstanding Options or


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Purchases may be exercised or made; (vi) determine whether restrictions
including, without limitation, repurchase options or forfeiture provisions are
to be imposed on shares subject to Options, Awards and Purchases and the nature
of such restrictions, if any; and (vii) interpret the Plan and any Stock Right
and prescribe, amend and rescind rules and regulations relating to the Plan. If
the Committee determines to issue an Option, it shall take whatever actions it
deems necessary, under Section 422 of the Code and the regulations promulgated
thereunder, to ensure that such Option is not treated as an Incentive Stock
Option. The interpretation and construction by the Committee of any provisions
of the Plan or of any Stock Right granted under the Plan shall be final unless
otherwise determined by the Board and shall be binding on all interested
parties. The Committee may from time to time adopt and amend such rules and
regulations for carrying out the Plan as it may deem advisable. No member of the
Board or the Committee shall be liable for any action or determination relating
to the Plan or any Stock Right granted under it.

                  B. COMMITTEE ACTIONS. The Committee may select one of its
members as its chairman, and shall hold meetings at such times and places as it
may determine. A majority of the Committee shall constitute a quorum and acts of
a majority of the members of the Committee at a meeting at which a quorum is
present, or acts reduced to or approved in writing by all the members of the
Committee (if consistent with applicable state law), shall be the valid acts of
the Committee. From time to time the Board may increase the size of the
Committee and appoint additional members thereof, remove members (with or
without cause) and appoint new members in substitution therefor, fill vacancies
however caused, or remove all members of the Committee and thereafter directly
administer the Plan.

                  C. GRANT OF STOCK RIGHTS TO BOARD MEMBERS. Stock Rights may be
granted to members of the Board. All grants of Stock Rights to members of the
Board shall in all respects be made in accordance with the provisions of this
Plan applicable to other eligible persons. Members of the Board who either (i)
are eligible to receive grants of Stock Rights pursuant to the Plan or (ii) have
been granted Stock Rights may vote on any matters affecting the administration
of the Plan or the grant of any Stock Rights pursuant to the Plan, except that
no such member shall act upon the granting to himself or herself of Stock
Rights, but any such member may be counted in determining the existence of a
quorum at any meeting of the Board during which action is taken with respect to
the granting to such member of Stock Rights.

                  D. PERFORMANCE-BASED COMPENSATION. The Board, in its
discretion, may take such action as may be necessary to ensure that Stock Rights
granted under the Plan qualify as "qualified performance-based compensation"
within the meaning of Section 162(m) of the Code and applicable regulations
promulgated thereunder


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("Performance-Based Compensation"). Such action may include, in the Board's
discretion, each or both of the following: (i) if the Board determines that
Stock Rights granted under the Plan generally shall constitute Performance-Based
Compensation, the Plan shall be administered, to the extent required for such
Stock Rights to constitute Performance-Based Compensation, by a Committee
consisting solely of two or more "outside directors" (as defined in applicable
regulations promulgated under Section 162(m) of the Code), and (ii) Stock Rights
granted under the Plan may be subject to such other terms and conditions as are
necessary for compensation recognized in connection with the exercise or
disposition of such Stock Rights or the disposition of Common Stock acquired
pursuant to such Stock Rights, to constitute Performance-Based Compensation.

         3. ELIGIBLE EMPLOYEES AND OTHERS. Options, Awards and authorizations to
make Purchases may be granted to any employee, officer or director (whether or
not also an employee), consultant or advisor 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. The granting of any
Stock Right to any individual shall neither entitle that individual to, nor
disqualify such individual from, participation in any other grant of Stock
Rights.

         4. STOCK. The stock subject to Stock Rights shall be authorized but
unissued shares of Common Stock of the Company, par value $0.05 per share (the
"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 1,000,000, subject to adjustment as provided in paragraph 12. If any Stock
Right 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 any shares of Common Stock issued pursuant to a Stock
Right shall be forfeited for any reason, the unpurchased or forfeited shares of
Common Stock subject to such Stock Right shall again be available for grants of
Stock Rights under the Plan.

         No Participant may be granted Stock Rights to acquire, in the
aggregate, more than 500,000 shares of Common Stock, subject to adjustment as
provided in paragraph 12G, under the Plan during any fiscal year of the Company.
If any Stock Right 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 any shares of Common Stock issued pursuant
to a Stock Right shall be forfeited for any reason, the shares subject to such
Stock Right shall be included in the determination of the aggregate number of
shares of Common Stock deemed to have been granted to such Participant under the
Plan.



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         5. GRANTING OF STOCK RIGHTS. Stock Rights may be granted under the Plan
at any time on or after September 15, 1998 and prior to September 14, 2008. 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.

         6. MINIMUM PRICE.

                  A. PRICE FOR OPTIONS, AWARDS AND PURCHASES. The exercise price
per share specified in the agreement relating to each Option granted, and the
purchase price per share of stock granted in any Award or authorized as a
Purchase, under the Plan may not be less than the fair market value of the
Common Stock of the Company on the date of grant.

                  B. DETERMINATION OF FAIR MARKET VALUE. If the Company's Common
Stock is actively traded in an established over-the-counter market, the fair
market value of such Common Stock shall be the mean between the bid and ask
prices quoted in such over-the-counter market at the close of the market on the
trading day nearest preceding the date of grant. If such Common Stock is listed
on any national exchange, or traded in the Nasdaq National Market, the mean
between the high and low sale prices quoted on such exchange or market on the
trading day nearest preceding the date of the granting of the Stock Right shall
be taken as such fair market value. If the Common Stock is not publicly traded,
the fair market value shall be determined from time to time by the Board of
Directors.

         7. STOCK RIGHT DURATION. Subject to earlier termination as provided in
any Individual Stock Right Agreement, each Stock Right shall expire on the date
specified by the Committee, but no more than ten years from the date of grant.

         8. EXERCISE OF OPTION. Subject to the provisions of paragraphs 9
through 11, each Option granted under the Plan shall be exercisable as follows:

                  A. VESTING. The Option shall either 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.



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                  C. PARTIAL EXERCISE.Each Option or installment may be
exercised at any time or from time to time, in whole or in part, for a minimum
of one hundred (100) shares 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 that any installment of any Option becomes exercisable.

         9. TERMINATION OF STOCK RIGHTS. A Stock Right shall be subject to such
termination provisions as specified in any Individual Stock Right Agreement but
in no event later than the specified expiration date of the Stock Right.

         10. TRANSFERABILITY. Any Option or right to make a Purchase granted
pursuant to this Plan shall not be assignable or transferable except by will or
by the laws of descent and distribution or pursuant to a valid domestic
relations order. During the lifetime of the Participant, any Stock Right shall
be exercisable only by the Participant to whom the Stock Right is granted; any
Stock Right granted hereunder shall be null and void and without effect upon the
bankruptcy of the Participant to whom the Stock Right is granted, or upon any
attempted assignment or transfer, including without limitation, any purported
assignment, whether voluntary or by operation of law, sale, pledge,
hypothecation or other disposition, attachment, trustee process or similar
process, whether legal or equitable, upon such Stock Right.

         11. TERMS AND CONDITIONS OF STOCK RIGHTS. Stock Rights shall be
evidenced by written 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 this Plan 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 upon
exercise of Stock Rights or grant of Awards. The Committee may from time to time
confer authority and responsibility on one or more of its own members and/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.

         12. ADJUSTMENTS. Upon the occurrence of any of the following events, a
Participant's rights with respect to Stock Rights granted to such Participant
hereunder shall be adjusted as hereinafter provided, unless otherwise
specifically provided in the Individual Stock Right Agreement between the
Participant and the Company.

                  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



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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 Stock Rights 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. Upon any sale of all or
substantially all of the assets of the Company, or upon any merger,
consolidation or tender offer in respect of which the stockholders holding all
of the Company's outstanding voting securities immediately prior to the
consummation thereof hold less than 50% of all of the Company's outstanding
voting securities immediately after such consummation (each of the foregoing
sale, merger, consolidation or tender offer hereinafter called an
"Acquisition"), then: (i) the date upon which all then outstanding Stock Rights
granted under this Plan become fully vested and exercisable shall be
automatically accelerated to occur immediately prior to the consummation of such
Acquisition; provided, however, that any such then outstanding Stock Rights
which are not thereupon exercised in full immediately prior to the consummation
of such Acquisition shall thereupon terminate, and (ii) the date(s) upon which
all then outstanding repurchase, forfeiture or other similar restrictions, if
any, (but not any securities law restrictions which may apply to such stock or
its disposition) on shares of stock subject to Stock Rights or granted pursuant
to an Award shall lapse shall be automatically accelerated to occur immediately
prior to the consummation of such Acquisition.

                  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, a Participant upon exercising a Stock Right shall be entitled to
receive for the purchase price paid upon such exercise the securities as
determined under the terms of the recapitalization or reorganization he or she
would have then received if he or she had exercised such Stock Right prior to
such recapitalization or reorganization.

                  D. DISSOLUTION OR LIQUIDATION. In the event of the proposed
dissolution or liquidation of the Company, each Stock Right 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.

                  E. 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 Stock Rights. No



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adjustments shall be made for dividends paid in cash or in property other than
securities of the Company.

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

                  G. ADJUSTMENTS. Upon the happening of any of the events
described in subparagraphs A 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 as well as
the per-Participant grant limit set forth in paragraph 4 shall also be
appropriately adjusted to reflect the events described in such subparagraphs.
The Committee or the Successor Board shall determine the specific adjustments to
be made under this paragraph 12 and, subject to paragraph 2, its determination
shall be conclusive and shall be binding on all interested parties.

         13. EXERCISE OF STOCK RIGHT. Subject to the terms and conditions of
this Plan and any Individual Stock Right Agreement, a Stock Right granted
hereunder shall be exercisable in whole or in part by giving written notice to
the Company by mail or in person addressed to Treasurer, Hadco Corporation, 12A
Manor Parkway, Salem, New Hampshire 03079, stating the number of shares with
respect to which the Stock Right is being exercised, accompanied by payment in
full for such shares, which payment may be made (a) in United States dollars in
cash or by check, or (b) at the discretion of the Committee, through delivery of
shares of Common Stock having a fair market value equal as of the date of the
exercise to the cash exercise price of the Stock Right, or (c) at the discretion
of the Committee and consistent with applicable law, through the delivery of an
assignment to the Company of a sufficient amount of the proceeds from the sale
of the Common Stock acquired upon exercise of the Stock Right and an
authorization to the broker or selling agent to pay that amount to the Company,
which sale shall be at the Participant's direction at the time of exercise, or
(d) at the discretion of the Committee, by any combination of (a), (b) and (c)
above. There shall be no such exercise at any one time as to fewer than one
hundred (100) shares or all of the shares then purchasable by the person or
persons exercising the Stock Right, if fewer than one hundred (100) shares. A
copy of such notice shall be provided to Hamilton & Dahmen, LLP, 73 Tremont
Street, Boston, Massachusetts 02108, or to such other counsel as the Company may
hereafter designate, and to the Bank of Boston, Shareholder Services Division,
Post Office Box 644, Boston, Massachusetts 02102, or to such other Stock
Transfer Agent as the Company may hereafter designate. The Transfer Agent shall,
on behalf of the Company, prepare a certificate or certificates representing
such shares acquired pursuant to exercise of the Stock Right, shall register the
Participant as the owner of such shares on the books of the Company and shall
cause the fully executed certificate(s) representing such shares



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to be delivered to the Participant as soon as practicable after payment of the
purchase price in full. The holder of a Stock Right shall not have any rights as
a shareholder with respect to the shares covered by the Stock Right, except to
the extent that one or more certificates for such shares shall be issued upon
the due exercise of the Stock Right or the grant of an Award.

         14. RESTRICTIONS ON ISSUANCE OF SHARES. Notwithstanding the provisions
of Section 13 of the Plan, the Company shall have no obligation to issue or
deliver any certificate or certificates upon exercise of a Stock Right or the
grant of an Award or to remove restrictions from shares previously delivered
under the Plan until the following applicable conditions shall be satisfied in
the judgment of the Company:

                  (i) the shares with respect to which the Stock Right has been
         exercised or the grant of an Award has been made are at the time of the
         issue of such shares effectively registered under applicable Federal
         and State securities acts as now in force or hereafter amended;

                  (ii) Counsel for the Company shall have given an opinion that
         such shares are exempt from registration under Federal and State
         securities acts as now in force or hereafter amended;

                  (iii) all conditions of the Stock Right have been met or
         removed to the satisfaction of the Company; or

                  (iv) the Participant has executed and delivered to the Company
         such representations or agreements as the Company may consider
         appropriate to satisfy the requirements of any applicable laws, rules
         or regulations;

and until the Company has complied with all applicable laws and regulations,
including without limitation all regulations required by any stock exchange upon
which the Company's outstanding Common Stock is then listed. The Company may
place appropriate legends on shares of stock subject to Stock Rights in
accordance with applicable securities law rules and regulations and to evidence
any restrictions placed on such stock.

         The Company shall use its best efforts to bring about compliance with
the above conditions within a reasonable time, except that the Company shall be
under no obligation to cause a registration statement or a post-effective
amendment to any registration statement to be prepared at its expense solely for
the purpose of covering the issue of shares in respect of which any Stock Right
may be exercised or Award made.



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         Any stock purchased or granted under the Plan prior to shareholder
approval of the Plan, in addition to any restrictions set forth in the
Individual Stock Right Agreement, may not be sold, assigned, mortgaged,
transferred, pledged, hypothecated or encumbered in any way and will be held in
escrow by the Company until shareholder approval for the Plan is obtained, and
if such shareholder approval is not obtained by June 12, 1999, the purchase or
grant of such stock, any Stock Right granted hereunder and this Plan will be
automatically rescinded and the purchase price returned to purchasing
Participants without interest.

         15. REPRESENTATIONS OF PARTICIPANT. The Company may require the
Participant to deliver such written warranties and representations upon exercise
of the Stock Right or the grant of an Award that the Company deems reasonable or
necessary, including without limitation a representation that a purchase of
shares under the Stock Right is made for investment and not with a view to their
distribution (as that term is used in the Securities Act of 1933).

         16. MODIFICATION OF OUTSTANDING STOCK RIGHTS. The Committee or the
Board of Directors may accelerate the exercisability of any outstanding Stock
Right, may accelerate the lapse of, or terminate, some or all restrictions on
Common Stock subject to a Stock Right, and may authorize changes to any
outstanding Stock Right with the consent of the Participant (including, without
limitation, to extend the term of a Stock Right upon termination of employment
to a date not later than ten (10) years from the original grant date) when and
subject to such conditions as are deemed to be in the best interests of the
Company and in accordance with the purposes of the Plan.

         17. APPROVAL OF STOCKHOLDERS. The Plan shall be subject to approval by
the affirmative vote of stockholders holding at least a majority of the voting
stock of the Company voting in person or by proxy at or by June 12, 1999, and
the Plan shall take effect as of the date of adoption immediately upon such
approval.

         18. TERM, TERMINATION AND AMENDMENT OF PLAN. The Plan shall expire at
the end of the business day on September 14, 2008 (except as to Stock Rights
outstanding on that date). The Board may at any time terminate the Plan or make
such modification or amendment thereof as it deems advisable; provided, however,
that except as provided in Section 12 the Board may not, without approval of the
stockholders of the Company obtained in the manner stated in Section 17 (i)
increase the maximum number of shares for which Stock Rights may be granted
under the Plan, or (ii) extend the expiration date of the Plan. Termination or
any modification or amendment of the Plan shall not, without consent of a
Participant, alter or impair his or her rights under a Stock Right previously
granted to him or her.



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         19. APPLICATION OF FUNDS. The proceeds received by the Company from the
sale of shares pursuant to Stock Rights authorized under the Plan shall be used
for general corporate purposes.

         20. WITHHOLDING OF ADDITIONAL INCOME TAXES. Upon any exercise of any
Stock Right or the vesting or transfer of restricted stock or securities
acquired on the exercise of a Stock Right hereunder, or the making of a
distribution or other payment with respect to such stock or securities, or the
purchase or award of any stock, the Company may withhold taxes in respect of
amounts that constitute compensation includable in gross income. The Committee
in its discretion may condition (i) the exercise or grant of a Stock Right, or
(ii) the vesting or transferability of restricted stock or securities acquired
by the grant of or the exercise of a Stock Right, on the Participant's making
satisfactory arrangement for such withholding. Such arrangement may include
payment by the Participant in cash or by check of the amount of the withholding
taxes or, at the discretion of the Committee, by the Participant's delivery of
previously held shares of Common Stock or the withholding of shares from the
shares of Common Stock otherwise deliverable upon exercise or grant of a Stock
Right, with such shares in each case having an aggregate fair market value (as
determined by the Board) equal to the amount of such withholding taxes. The
Company may, to the extent permitted by law, deduct any such tax obligations
from any payment of any kind otherwise due to the Participant.

         21. NO RIGHT TO EMPLOYMENT OR OTHER STATUS. Nothing in the Plan nor any
grant of any Stock Right shall be deemed or construed to give any Participant
the right to be retained in employment or the service of the Company or any
Related Corporation for any period of time. The Company expressly reserves the
right at any time to dismiss or otherwise terminate its relationship with a
Participant free from any liability or claim under the Plan or any Stock Right.

         22. 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.

         23. GOVERNING LAW. 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 then be organized.


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         24. REPRICING. Without the prior approval of the Company's stockholders
obtained in the manner stated in section 17, Options issued under the plan will
not be repriced, replaced or regranted through cancellation or by lowering the
Option exercise price of a previously granted Option.