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                                                                   Exhibit 10.9

                  AMENDMENT NO. 1 DATED AS OF MARCH 13, 1998 TO

                          AGREEMENT AND PLAN OF MERGER

         WHEREAS, Hadco Corporation, a Massachusetts corporation ("Parent"),
Hadco Acquisition Corp. II, a Delaware corporation and a direct wholly-owned
subsidiary of Parent ("Sub"), and Continental Circuits Corp., a Delaware
corporation (the "Company") have entered into an Agreement and Plan of Merger,
dated as of February 16, 1998 (the "Agreement");

         WHEREAS, the parties to the Agreement desire to amend and supplement
the agreement in certain respects as set forth herein;

         NOW, THEREFORE, in consideration of the foregoing and the
representations, warranties, covenants and agreements herein contained, the
parties hereto, intending to be legally bound, hereby agree as follows:

         SECTION 1. DEFINITIONS. Capitalized terms used herein and not defined
shall have the respective meanings set forth in the Agreement.

         SECTION 2. AMENDMENT. Exhibit A of the Agreement shall be amended to
read in its entirety as follows: 
     
                                                                       Exhibit A

         The capitalized terms used in this Exhibit A shall have the respective
meanings given to such terms in the Agreement and Plan of Merger, dated as of
February 16, 1998, among Hadco Corporation, Hadco Acquisition Corp. II and
Continental Circuits Corp. (the "Merger Agreement") to which this Exhibit A is
attached.

                             CONDITIONS TO THE OFFER

         Notwithstanding any other provision of the Offer, Sub shall not be
required to accept for payment or, subject to any applicable rules and
regulations of the SEC, including Rule 14e-1(c) under the Exchange Act (relating
to Sub's obligation to pay for or return tendered Shares promptly after
expiration or termination of the Offer), to pay for any Shares tendered, and may
postpone the acceptance for payment or, subject to the restriction referred to
above, payment for any Shares tendered, and may amend (subject to Section 1.1(b)
of the Merger Agreement) or terminate the Offer (whether or not any Shares have
theretofore been purchased or paid for) if, (i) there has not been validly
tendered and not withdrawn prior to the time the Offer shall otherwise expire a
number of Shares which constitutes at least 90% of the Shares outstanding on a
fully-diluted basis on the date of purchase ("on a fully-diluted basis" having
the following meaning, as of any date: the number of Shares outstanding,
together with Shares the Company may be then required to issue pursuant to
obligations outstanding at that date under stock option, stock purchase or other
benefit plans or otherwise); (ii) all material regulatory and related approvals
have not been obtained prior to the


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expiration of the Offer or made on terms reasonably satisfactory to Sub; (iii)
any applicable waiting periods under the HSR Act shall not have expired or been
terminated prior to the expiration of the Offer; or (iv) at any time on or after
the date of the Merger Agreement and before the expiration of the Offer, such
Shares any of the following events shall occur:

         (A) There shall have been threatened, instituted or pending any action,
proceeding, application or counterclaim by or before any court or governmental,
regulatory or administrative agency, authority or tribunal, domestic, foreign or
supranational (other than actions, proceedings, applications or counterclaims
filed or initiated by Sub), which (i) seeks to challenge the acquisition by Sub
of the Shares, restrain, prohibit or delay the making or consummation of the
Offer or the Merger or any other merger or business combination involving Sub or
any of its affiliates and the Company or any of its subsidiaries, prohibit the
performance of any of the contracts or other agreements entered into by Sub or
any of its affiliates in connection with the acquisition of the Company or the
Shares, or obtain any material damages in connection with any of the foregoing,
(ii) seeks to make the purchase of or payment for, some or all of the Shares
pursuant to the Offer, the Merger or otherwise, illegal, (iii) seeks to impose
limitations on the ability of Sub or the Company or any of their respective
affiliates or subsidiaries effectively to acquire or hold, or requiring Sub, the
Company or any of their respective affiliates or subsidiaries to dispose of or
hold separate, any portion of the assets or the business of Sub or its
affiliates or the Company or its subsidiaries, or impose limitations on the
ability of Sub, the Company or any of their respective affiliates or
subsidiaries to continue to conduct, own or operate all or any portion of their
businesses and assets as heretofore conducted, owned or operated, (iv) seeks to
impose or may result in material limitations on the ability of Sub or any of its
affiliates to exercise full rights of ownership of the Shares purchased by them,
including, without limitation, the right to vote the Shares purchased by them on
all matters properly presented to the stockholders of the Company, or the right
to vote any shares of capital stock of any subsidiary directly or indirectly
owned by the Company, (v) is reasonably likely to result in a material
diminution in the benefits expected to be derived by Sub as a result of the
transactions contemplated by the Offer, including the Merger, (vi) seeks to
impose voting, procedural, price or other requirements in addition to those
under Delaware Law and federal securities laws (each as in effect on the date of
the Offer to Purchase) or any material condition to the Offer in any such case
which is unacceptable (in its reasonable judgment) to Sub or (vii) challenges or
adversely and materially affects the financing of the Offer;

         (B) There shall have been formally proposed, sought, promulgated,
enacted, entered or made applicable to the Offer or the Merger or enforced by
any domestic, foreign or supranational government or any governmental,
administrative or regulatory authority or agency or by any court or tribunal,
domestic, foreign or supranational, any statute, rule, regulation, judgment,
decree, order or injunction that might result in any of the consequences
referred to in clauses (i) through (vii) of paragraph (A) above;

         (C) There shall have occurred any of the following which, in the good
faith judgment of the Parent and Sub, make it inadvisable to proceed with the
Offer and acceptance for payment of, and payment for, the Shares (1) any general
suspension of trading in, or limitation on prices for, securities on any
national securities exchange or in the over-the-counter market in the United
States, (2) the declaration of a banking moratorium or any suspension of
payments in respect of banks in


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the United States, (3) the commencement of a war, armed hostilities or other
international or national calamity, directly or indirectly involving the United
States, (4) any limitations (whether or not mandatory) imposed by any
governmental authority on, or any event which might have material adverse
significance with respect to, the nature or extension of credit or further
extension of credit by banks or other lending institutions, (5) any significant
adverse change in the equity or debt markets in the United States which shall be
continuing as of the expiration of the Offer, or (6) in the case of any of the
foregoing, a material acceleration or worsening thereof;

         (D) The representations and warranties of the Company contained in the
Merger Agreement (without giving effect to any "Material Adverse Effect",
"materiality" or similar qualifications contained therein) shall not be true and
correct in all material respects (for purpose of this clause, a failure of the
representations and warranties to be true and correct in all material respects
shall mean a failure or series of failures the result of which impairs the value
of the Company or could reasonably be expected to impair the value of the
Company by more than $3,000,000 as of the date of the consummation of the Offer
as though made on and as of such date except (1) for changes specifically
permitted by the Merger Agreement and (2) that those representations and
warranties which address matters only as of a particular date shall remain true
and correct as of such date;

         (E) The obligations of the Company contained in the Merger Agreement
(without giving effect to any "Material Adverse Effect", "materiality" or
similar qualifications contained therein) shall not have been performed or
complied with in all material respects by the Company;

         (F) The Merger Agreement shall have been terminated in accordance with
its terms;

         (G) Prior to the purchase of Shares pursuant to the Offer, an
Acquisition Proposal for the Company exists and the Board shall have withdrawn
or materially modified or changed (including by amendment of the Schedule 14D-9)
in a manner adverse to Sub its recommendation of the Offer, the Merger Agreement
or the Merger;

         (H) Any person or group (other than Parent and Sub) shall have entered
into a definitive agreement or agreement in principle with the Company with
respect to a merger, consolidation or other business combination with the
Company; or

         (I) The Company shall have suffered a material adverse change in its
business, operations, assets or condition (financial or otherwise).

         The foregoing conditions are for the sole benefit of Sub and its
affiliates and may be asserted by Sub regardless of the circumstances (other
than any action or inaction by Parent, Sub or any of their affiliates) giving
rise to any such condition or may be waived by Sub, in whole or in part, from
time to time in its sole discretion, except as otherwise provided in the
Agreement. The failure by Sub at any time to exercise any of the foregoing
rights shall not be deemed a waiver of any such right and each such right shall
be deemed an ongoing right and may be asserted at any time and from time to
time. Any reasonable determination by Sub concerning any of the events described
herein shall be final and binding.


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
signed by their respective officers thereunto duly authorized, all as of the
date first written above.

                                    HADCO CORPORATION

                                    By:      /s/ Timothy P. Losik
                                           -------------------------------------
                                    Name:    Timothy P. Losik
                                           -------------------------------------
                                    Title:   Senior Vice President
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                                    HADCO ACQUISITION CORP. II

                                    By:    /s/ Timothy P. Losik
                                           -------------------------------------
                                    Name:  Timothy P. Losik
                                           -------------------------------------
                                    Title: Vice President, Treasurer & Secretary
                                           -------------------------------------

                                    CONTINENTAL CIRCUITS CORP.

                                    By:    /s/ Frederick G. McNamee III
                                           -------------------------------------
                                    Name:  Frederick G. McNamee III
                                           -------------------------------------
                                    Title: President and Chief Executive Officer
                                           -------------------------------------


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