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                                                                     EXHIBIT 4.3

                     EXCHANGEABLE SHARE SUPPORT AGREEMENT

     MEMORANDUM OF AGREEMENT made as of the 27th day of July, 2000.

AMONG:

                    SMTC CORPORATION,
                    a corporation existing under the laws of
                    the State of Delaware
                    (hereinafter referred to as "SMTC"),

                                                       OF THE FIRST PART,

                               - and -

                    SMTC NOVA SCOTIA COMPANY,
                    an unlimited company existing under the laws of
                    the Province of Nova Scotia
                    (hereinafter referred to as "SMTC Nova Scotia"),

                                                       OF THE SECOND PART,

                               - and -

                    SMTC MANUFACTURING CORPORATION
                    OF CANADA,
                    a corporation existing under the laws of
                    the Province of Ontario
                    (hereinafter referred to as "SMTC Canada"),

                                                      OF THE THIRD PART.

          WHEREAS, pursuant to an underwriting agreement dated as of July 20,
2000 and a prospectus dated July 20, 2000 filed with the securities regulatory
authorities in each of the provinces of Canada (the "Prospectus"), SMTC Canada
has agreed to issue 4,375,000 non-voting exchangeable shares of SMTC Canada
("Exchangeable Shares") to the public in an initial public offering (the
"Initial Public Offering") and may, from time to time, issue additional
Exchangeable Shares or securities exchangeable for or convertible into or
carrying rights to acquire Exchangeable Shares;

          AND WHEREAS SMTC Canada will, on the date of this agreement, issue
1,469,445 Exchangeable Shares to certain SMTC Canada shareholders on the
conversion of previously issued SMTC Canada Class L exchangeable shares;

          AND WHEREAS each Exchangeable Share is exchangeable at the holder's
option at any time, without further payment, for one share of common stock of
SMTC (the "SMTC Common Stock");
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          AND WHEREAS coincident with and as part of the issue of Exchangeable
Shares pursuant to the Initial Public Offering, SMTC, SMTC Nova Scotia and SMTC
Canada are to execute a support agreement substantially in the form of this
agreement;

          NOW THEREFORE in consideration of the respective covenants and
agreements provided in this agreement and for other good and valuable
consideration (the receipt and sufficiency of which are hereby acknowledged),
the parties hereto covenant and agree as follows:

                                   ARTICLE 1
                        DEFINITIONS AND INTERPRETATION

1.1  Definitions

     Each term denoted herein by initial capital letters and not otherwise
defined herein shall have the meaning ascribed thereto in the rights,
privileges, restrictions and conditions attaching to the Exchangeable Shares
(collectively, the "Exchangeable Share Provisions"), unless the context requires
otherwise.

1.2  Interpretation Not Affected by Headings

     The division of this agreement into Articles, Sections and other portions
and the insertion of headings are for convenience of reference only and shall
not affect the construction or interpretation of this agreement. Unless
otherwise indicated, all references to an "Article" or "Section" followed by a
number and/or letter refer to the specified Article or Section of this
agreement. The terms "this agreement", "hereof", "herein" and "hereunder" and
similar expressions refer to this agreement and not to any particular Article,
Section or other portion hereof, and include any agreement or instrument
supplementary or ancillary hereto.

1.3  Number, Gender

     In this agreement, unless the context otherwise requires, words importing
the singular number only shall include the plural and vice versa, and words
importing any gender shall include all genders.

1.4  Date for Any Action

     If any date on which any action is required to be taken under this
agreement is not a Business Day, such action shall be required to be taken on
the next succeeding Business Day.

                                   ARTICLE 2
                       COVENANTS OF SMTC AND SMTC CANADA

2.1  Covenants Regarding Exchangeable Shares

     So long as any Exchangeable Shares (other than Exchangeable Shares owned by
SMTC or its Affiliates) remain outstanding, SMTC will:

                                      -2-
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     (a)  not declare or pay any dividend on the shares of SMTC Common Stock
          unless (i) SMTC Canada shall (w) simultaneously declare or pay, as the
          case may be, an equivalent dividend (as provided for in the
          Exchangeable Share Provisions) on the Exchangeable Shares (an
          "Equivalent Dividend"), and (x) have sufficient money or other assets
          or authorized but unissued securities available to enable the due
          declaration and the due and punctual payment, in accordance with
          applicable law, of any Equivalent Dividend, or (ii) SMTC Canada shall
          (y) simultaneously subdivide the Exchangeable Shares in lieu of a
          stock dividend thereon (as provided for in the Exchangeable Share
          Provisions) (an "Equivalent Stock Subdivision"), and (z) have
          sufficient authorized but unissued securities available to enable the
          Equivalent Stock Subdivision;

     (b)  advise SMTC Canada sufficiently in advance of the declaration by SMTC
          of any dividend on the shares of SMTC Common Stock and take all such
          other actions as are reasonably necessary, in co-operation with SMTC
          Canada, to ensure that (i) the respective declaration date, record
          date and payment date for an Equivalent Dividend shall be the same as
          the declaration date, record date and payment date for the
          corresponding dividend on the shares of SMTC Common Stock or, (ii) the
          record date and effective date for an Equivalent Stock Subdivision
          shall be the same as the record date and payment date for the
          corresponding stock dividend on the shares of SMTC Common Stock;

     (c)  ensure that the record date for any dividend declared on the shares of
          SMTC Common Stock is not less than 10 Business Days after the
          declaration date of such dividend;

     (d)  take all such actions and do all such things as are reasonably
          necessary or desirable to enable and permit SMTC Canada, in accordance
          with applicable law, to pay and otherwise perform its obligations with
          respect to the satisfaction of the Company Liquidation Amount, the
          Retraction Price or the Redemption Price in respect of each issued and
          outstanding Exchangeable Share (other than Exchangeable Shares owned
          by SMTC or its Affiliates) upon the liquidation, dissolution or
          winding-up of SMTC Canada, the delivery of a Retraction Request by a
          holder of Exchangeable Shares or a redemption of Exchangeable Shares
          by SMTC Canada, as the case may be, including without limitation all
          such actions and all such things as are necessary or desirable to
          enable and permit SMTC Canada to cause to be delivered shares of SMTC
          Common Stock to the holders of Exchangeable Shares in accordance with
          the provisions of Articles 5, 6 or 7, as the case may be, of the
          Exchangeable Share Provisions;

     (e)  take all such actions and do all such things as are reasonably
          necessary or desirable to enable and permit SMTC Nova Scotia, in
          accordance with applicable law, to perform its obligations arising
          upon the exercise by it of the Liquidation Call Right, the Retraction
          Call Right or the Redemption Call Right, including without limitation
          all such actions and all such things as are necessary or desirable to
          enable and permit SMTC Nova Scotia to cause to be delivered shares of
          SMTC Common Stock to the holders of Exchangeable Shares in accordance
          with the

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          provisions of the Liquidation Call Right, the Retraction Call Right or
          the Redemption Call Right, as the case may be; and

     (f)  if it becomes a "specified financial institution" (as such term is
          defined in the Income Tax Act (Canada)) or does not deal at arm's
          length with such a person, take all such actions and do all such
          things as are reasonably necessary or desirable to cause SMTC Nova
          Scotia to exercise the Retraction Call Right if requested to do so by
          a holder of Exchangeable Shares making a Retraction Request.

2.2  Segregation of Funds

     SMTC will cause SMTC Canada or SMTC Nova Scotia, as the case may be, to
deposit a sufficient amount of funds in a separate account of SMTC Canada or
SMTC Nova Scotia and segregate a sufficient amount of such other assets and
property as is necessary to enable SMTC Canada to pay dividends when due and to
enable SMTC Canada or SMTC Nova Scotia to pay or otherwise satisfy their
respective obligations under Articles 5, 6 or 7 of the Exchangeable Share
Provisions, as applicable.

2.3  Reservation of SMTC Common Stock

     SMTC hereby represents, warrants and covenants in favour of SMTC Canada and
SMTC Nova Scotia that SMTC has reserved for issuance and will, at all times
while any Exchangeable Shares (other than Exchangeable Shares held by SMTC or
its Affiliates) are outstanding, keep available, free from pre-emptive and other
rights, out of its authorized and unissued capital stock such number of shares
of SMTC Common Stock (or other shares or securities into which shares of SMTC
Common Stock may be reclassified or changed as contemplated by Section 2.7) (a)
as is equal to the sum of (i) the number of Exchangeable Shares issued and
outstanding from time to time, and (ii) the number of Exchangeable Shares
issuable upon the exercise of all rights, options or other entitlements to
acquire Exchangeable Shares outstanding from time to time, and (b) as are now
and may hereafter be required to enable and permit SMTC to meet its obligations
under the Voting and Exchange Trust Agreement and under any other security or
commitment pursuant to which SMTC may now or hereafter be required to issue
shares of SMTC Common Stock, to enable and permit SMTC Nova Scotia to meet its
obligations under each of the Liquidation Call Right, the Retraction Call Right
and the Redemption Call Right and to enable and permit SMTC Canada to meet its
obligations hereunder and under the Exchangeable Share Provisions.

2.4  Notification of Certain Events

     In order to assist SMTC in complying with its obligations hereunder and to
permit SMTC Nova Scotia to exercise the Liquidation Call Right, the Retraction
Call Right and the Redemption Call Right, SMTC Canada will notify SMTC and SMTC
Nova Scotia of each of the following events at the time set forth below:

                                      -4-
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     (a)  in the event of any determination by the Board of Directors to
          institute voluntary liquidation, dissolution or winding-up proceedings
          with respect to SMTC Canada or to effect any other distribution of the
          assets of SMTC Canada among its shareholders for the purpose of
          winding-up its affairs, at least 60 days prior to the proposed
          effective date of such liquidation, dissolution, winding-up or other
          distribution;

     (b)  promptly, upon the earlier of receipt by SMTC Canada of notice of and
          SMTC Canada otherwise becoming aware of any threatened or instituted
          claim, suit, petition or other proceedings with respect to the
          involuntary liquidation, dissolution or winding-up of SMTC Canada or
          to effect any other distribution of the assets of SMTC Canada among
          its shareholders for the purpose of winding-up its affairs;

     (c)  immediately, upon receipt by SMTC Canada of a Retraction Request;

     (d)  on the same date on which notice of redemption is given to holders of
          Exchangeable Shares, upon the determination of a Redemption Date in
          accordance with the Exchangeable Share Provisions; and

     (e)  as soon as practicable upon the issuance by SMTC Canada of any
          Exchangeable Shares, rights, options or warrants to acquire
          Exchangeable Shares or other securities exchangeable for or
          convertible into Exchangeable Shares.

2.5  Delivery of SMTC Common Stock to SMTC Canada and SMTC Nova Scotia

     In furtherance of its obligations under Sections 2.1(d) and (e), upon
notice from SMTC Canada or SMTC Nova Scotia of any event that requires SMTC
Canada or SMTC Nova Scotia to cause to be delivered shares of SMTC Common Stock
to any holder of Exchangeable Shares, SMTC shall forthwith issue and deliver or
cause to be delivered to SMTC Canada or SMTC Nova Scotia the requisite number of
shares of SMTC Common Stock to be received by, and issued to or to the order of,
the former holder of the surrendered Exchangeable Shares, as SMTC Canada or SMTC
Nova Scotia shall direct. All such shares of SMTC Common Stock shall be duly
authorized and validly issued as fully paid and non-assessable and shall be free
and clear of any lien, claim or encumbrance. In consideration of the issuance
and delivery of each such share of SMTC Common Stock, SMTC Canada or SMTC Nova
Scotia, as the case may be, shall issue to SMTC, or, as SMTC shall direct,
common shares of SMTC Canada or SMTC Nova Scotia, cash, securities or other
property having equivalent value.

2.6  Qualification of SMTC Common Stock

     If any shares of SMTC Common Stock (or other shares or securities into
which shares of SMTC Common Stock may be reclassified or changed as contemplated
by Section 2.7) to be issued and delivered hereunder require registration or
qualification with or approval of or the filing of any document, including any
prospectus or similar document or the taking of any proceeding with or the
obtaining of any order, ruling or consent from any governmental or regulatory
authority under any Canadian or United States federal, provincial or state
securities or other law or regulation or pursuant to the rules and regulations
of any securities or other

                                      -5-
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regulatory authority or the fulfilment of any other Canadian or United States
legal requirement before such shares (or such other shares or securities) may be
issued by SMTC and delivered by SMTC at the direction of SMTC Nova Scotia or
SMTC Canada, if applicable, to the holder of surrendered Exchangeable Shares or
in order that such shares (or such other shares or securities) may be freely
traded thereafter (other than any restrictions of general application on
transfer of securities of an issuer that is not a "reporting issuer" or
equivalent within the meaning of Canadian provincial securities laws, or by
reason of a holder being a "control person" for purposes of Canadian provincial
securities law or an "affiliate" of SMTC for purposes of United States federal
or state securities law), SMTC will, in good faith, expeditiously take all such
actions and do all such things as are necessary or desirable to cause such
shares of SMTC Common Stock (or such other shares or securities) to be and
remain duly registered, qualified or approved under Canadian and/or United
States law, as the case may be. SMTC will, in good faith, expeditiously take all
such actions and do all such things as are reasonably necessary or desirable to
cause all shares of SMTC Common Stock (or such other shares or securities) to be
delivered hereunder to be listed, quoted or posted for trading on all stock
exchanges and quotation systems on which outstanding shares of SMTC Common Stock
(or such other shares or securities) have been listed by SMTC and remain listed
and are quoted or posted for trading at such time.

2.7 Economic Equivalence

     (a)  SMTC will not, without the prior approval of SMTC Canada and the prior
          approval of the holders of the Exchangeable Shares given in accordance
          with Section 10.2 of the Exchangeable Share Provisions:

          (i)   issue or distribute shares of SMTC Common Stock (or securities
                exchangeable for or convertible into or carrying rights to
                acquire shares of SMTC Common Stock) to the holders of all or
                substantially all of the then-outstanding shares of SMTC Common
                Stock by way of stock dividend or other distribution, other than
                an issue of shares of SMTC Common Stock (or securities
                exchangeable for or convertible into or carrying rights to
                acquire shares of SMTC Common Stock) to holders of shares of
                SMTC Common Stock who exercise an option to receive dividends in
                shares of SMTC Common Stock (or securities exchangeable for or
                convertible into or carrying rights to acquire shares of SMTC
                Common Stock) in lieu of receiving cash dividends; or

          (ii)  issue or distribute rights, options or warrants to the holders
                of all or substantially all of the then-outstanding shares of
                SMTC Common Stock entitling them to subscribe for or to purchase
                shares of SMTC Common Stock (or securities exchangeable for or
                convertible into or carrying rights to acquire shares of SMTC
                Common Stock); or

          (iii) issue or distribute to the holders of all or substantially all
                of the then-outstanding shares of SMTC Common Stock (A) shares
                or securities of SMTC of any class other than shares of SMTC
                Common Stock (other than shares convertible into or exchangeable
                for or carrying rights to

                                      -6-
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                acquire shares of SMTC Common Stock), (B) rights, options or
                warrants other than those referred to in Section 2.7(a)(ii), (C)
                evidences of indebtedness of SMTC or (D) assets of SMTC;

     unless the economic equivalent on a per share basis of such rights,
     options, securities, shares, evidences of indebtedness or other assets is
     issued or distributed simultaneously to holders of the Exchangeable Shares,
     in which case, for greater certainty, no approval of the holders of
     Exchangeable Shares is required.

(b)  SMTC will not, without the prior approval of SMTC Canada and the prior
     approval of the holders of the Exchangeable Shares given in accordance with
     Section 10.2 of the Exchangeable Share Provisions:

     (i)   subdivide, redivide or change the then-outstanding shares of SMTC
           Common Stock into a greater number of shares of SMTC Common Stock; or

     (ii)  reduce, combine, consolidate or change the then-outstanding shares of
           SMTC Common Stock into a lesser number of shares of SMTC Common
           Stock; or

     (iii) reclassify or otherwise change shares of SMTC Common Stock or effect
           an amalgamation, merger, reorganization or other transaction
           affecting shares of SMTC Common Stock;

     unless the same or an economically equivalent change shall simultaneously
     be made to, or in the rights of the holders of, the Exchangeable Shares, in
     which case, for greater certainty, no approval of the holders of
     Exchangeable Shares is required.

(c)  SMTC will ensure that the record date for any event referred to in Sections
     2.7(a) or 2.7(b) above, or (if no record date is applicable for such event)
     the effective date for any such event, is not less than five Business Days
     after the date on which such event is declared or announced by SMTC (with
     contemporaneous notification thereof by SMTC to SMTC Canada).

(d)  The Board of Directors shall determine, in good faith and in its sole
     discretion, economic equivalence for the purposes of any event referred to
     in Sections 2.7(a) or 2.7(b) and each such determination shall be
     conclusive and binding on SMTC. In making each such determination, the
     following factors shall, without excluding other factors determined by the
     Board of Directors to be relevant, be considered by the Board of Directors:

     (i)  in the case of any stock dividend or other distribution payable in
          shares of SMTC Common Stock, the number of such shares issued in
          proportion to the number of shares of SMTC Common Stock previously
          outstanding;

                                      -7-
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     (ii)  in the case of the issuance or distribution of any rights, options or
           warrants to subscribe for or purchase shares of SMTC Common Stock (or
           securities exchangeable for or convertible into or carrying rights to
           acquire shares of SMTC Common Stock), the relationship between the
           exercise price of each such right, option or warrant and the Current
           Market Price of a share of SMTC Common Stock;

     (iii) in the case of the issuance or distribution of any other form of
           property (including, without limitation, any shares or securities of
           SMTC of any class other than shares of SMTC Common Stock, any rights,
           options or warrants other than those referred to in Section
           2.7(d)(ii), any evidences of indebtedness of SMTC or any assets of
           SMTC), the relationship between the fair market value (as determined
           by the Board of Directors) of such property to be issued or
           distributed with respect to each outstanding share of SMTC Common
           Stock and the Current Market Price of a share of SMTC Common Stock;

     (iv)  in the case of any subdivision, redivision or change of the then-
           outstanding shares of SMTC Common Stock into a greater number of
           shares of SMTC Common Stock or the reduction, combination,
           consolidation or change of the then-outstanding shares of SMTC Common
           Stock into a lesser number of shares of SMTC Common Stock or any
           amalgamation, merger, reorganization or other transaction affecting
           shares of SMTC Common Stock, the effect thereof upon the then-
           outstanding shares of SMTC Common Stock; and

     (v)   in all such cases, the general taxation consequences of the relevant
           event to holders of Exchangeable Shares to the extent that such
           consequences may differ from the taxation consequences to holders of
           shares of SMTC Common Stock as a result of differences between
           taxation laws of Canada and the United States (except for any
           differing consequences arising as a result of differing marginal
           taxation rates and without regard to the individual circumstances of
           holders of Exchangeable Shares).

(e)  SMTC Canada agrees that, to the extent required, upon due notice from SMTC,
     SMTC Canada will use its best efforts to take or cause to be taken such
     steps as may be necessary for the purposes of ensuring that appropriate
     dividends are paid or other distributions are made by SMTC Canada, or
     subdivisions, redivisions or changes are made to the Exchangeable Shares,
     in order to implement the required economic equivalence with respect to the
     shares of SMTC Common Stock and Exchangeable Shares as provided for in this
     Section 2.7.

2.8 Tender Offers

     In the event that a tender offer, share exchange offer, issuer bid, take-
over bid or similar transaction with respect to shares of SMTC Common Stock
(each, an "Offer") is proposed by SMTC or is proposed to SMTC or its
shareholders and is recommended by the board of directors

                                      -8-
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of SMTC, or is otherwise effected or to be effected with the consent or approval
of the board of directors of SMTC, and the Exchangeable Shares are not redeemed
by SMTC Canada or purchased by SMTC Nova Scotia pursuant to the Redemption Call
Right, SMTC will use its reasonable efforts, expeditiously and in good faith, to
take all such actions and do all such things as are necessary or desirable to
enable and permit holders of Exchangeable Shares to participate in such Offer to
the same extent and on an economically equivalent basis as the holders of shares
of SMTC Common Stock, without discrimination. Without limiting the generality of
the foregoing, SMTC will use its reasonable efforts expeditiously and in good
faith to ensure that holders of Exchangeable Shares may participate in all such
Offers without being required to exercise their right to retract Exchangeable
Shares as against SMTC Canada (or, if so required, to ensure that any such
retraction shall be effective only upon, and shall be conditional upon, the
closing of the Offer and only to the extent necessary to tender to or deposit
under the Offer). Nothing herein shall affect the rights of SMTC Canada to
redeem (or SMTC Nova Scotia to purchase pursuant to the Redemption Call Right)
Exchangeable Shares, as applicable, in the event of an SMTC Control Transaction.

2.9  Ownership of Outstanding Shares

     Without the prior approval of SMTC Canada and the prior approval of the
holders of Exchangeable Shares given in accordance with Section 10.2 of the
Exchangeable Share Provisions, SMTC covenants and agrees in favour of SMTC
Canada that, as long as any outstanding Exchangeable Shares are owned by any
person or entity other than SMTC or any of its Affiliates, SMTC will be and
remain the direct or indirect beneficial owner of all issued and outstanding
voting shares in the capital of SMTC Canada and SMTC Nova Scotia.

2.10 SMTC and Affiliates Not to Vote Exchangeable Shares

     SMTC covenants and agrees that it will appoint and cause to be appointed
proxyholders with respect to all Exchangeable Shares held by it and its
Affiliates for the sole purpose of attending each meeting of holders of
Exchangeable Shares in order to be counted as part of the quorum for each such
meeting. SMTC further covenants and agrees that it will not, and will cause its
Affiliates not to, exercise any voting rights which may be exercisable by
holders of Exchangeable Shares from time to time pursuant to the Exchangeable
Share Provisions or pursuant to the provisions of the Business Corporations Act
(Ontario) (or any successor or other corporate statute by which SMTC Canada may
in the future be governed) with respect to any Exchangeable Shares held by it or
by its Affiliates in respect of any matter considered at any meeting of holders
of Exchangeable Shares.

2.11 Rule 10b-18 Purchases

     For greater certainty, nothing contained in this agreement, including
without limitation the obligations of SMTC contained in Section 2.8, shall limit
the ability of SMTC or SMTC Canada to make a "Rule l0b-18 Purchase" of shares of
SMTC Common Stock pursuant to Rule l0b-18 of the U.S. Securities Exchange Act of
1934, as amended, or any successor provisions thereof.

                                      -9-
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2.12 Stock Exchange Listing

     SMTC covenants and agrees in favour of SMTC Canada that, as long as any
outstanding Exchangeable Shares are owned by any person or entity other than
SMTC or any of its Affiliates, SMTC will use its reasonable best efforts to
maintain a listing for such Exchangeable Shares on a Canadian stock exchange.

                                  ARTICLE 3
                                SMTC SUCCESSORS

3.1  Certain Requirements in Respect of Combination

     SMTC shall not consummate any transaction (whether by way of
reconstruction, reorganization, consolidation, merger, transfer, sale, lease or
otherwise) whereby all or substantially all of its undertaking, property and
assets would become the property of any other Person or, in the case of a
merger, of the continuing corporation resulting therefrom unless, but may do so
if:

     (a)  such other Person or continuing corporation (the "SMTC Successor"), by
          operation of law, becomes, without more, bound by the terms and
          provisions of this agreement or, if not so bound, executes, prior to
          or contemporaneously with the consummation of such transaction, an
          agreement supplemental hereto and such other instruments (if any) as
          are reasonably necessary or advisable to evidence the assumption by
          the SMTC Successor of liability for all moneys payable and property
          deliverable hereunder and the covenant of such SMTC Successor to pay
          and deliver or cause to be delivered the same and its agreement to
          observe and perform all the covenants and obligations of SMTC under
          this agreement; and

     (b)  such transaction shall be upon such terms and conditions as
          substantially to preserve and not to impair in any material respect
          any of the rights, duties, powers and authorities of the other parties
          hereunder or the holders of Exchangeable Shares.

3.2  Vesting of Powers in Successor

     Whenever the conditions of Section 3.1 have been duly observed and
performed, the parties, if required by Section 3.1, shall execute and deliver a
supplemental agreement hereto and thereupon the SMTC Successor shall possess and
from time to time may exercise each and every right and power and shall be
subject to each and every obligation of SMTC under this agreement in the name of
SMTC or otherwise and any act or proceeding under any provision of this
agreement required to be done or performed by the board of directors of SMTC or
any officers of SMTC may be done and performed with like force and effect by the
directors or officers of such SMTC Successor.

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3.3  Wholly-Owned Subsidiaries

     Nothing herein shall be construed as preventing the amalgamation or merger
of any wholly-owned direct or indirect subsidiary of SMTC with or into SMTC or
the winding-up, liquidation or dissolution of any wholly-owned subsidiary of
SMTC provided that all of the assets of such subsidiary are transferred to SMTC
or another wholly-owned direct or indirect subsidiary of SMTC and any such
transactions are expressly permitted by this Article 3.

                                  ARTICLE 4
                                   GENERAL

4.1  Term

     This agreement shall come into force and be effective as of the date hereof
and shall terminate and be of no further force and effect at such time as no
Exchangeable Shares (or securities or rights convertible into or exchangeable
for or carrying rights to acquire Exchangeable Shares) are held by any person or
entity other than SMTC and any of its Affiliates.

4.2  Amendments, Modifications

     This agreement may not be amended or modified except by an agreement in
writing executed by SMTC Canada, SMTC Nova Scotia and SMTC and approved by the
holders of the Exchangeable Shares in accordance with Section 10.2 of the
Exchangeable Share Provisions.

4.3  Ministerial Amendments

     Notwithstanding the provisions of Section 4.2, the parties to this
agreement may in writing, at any time and from time to time, without the
approval of the holders of the Exchangeable Shares, amend or modify this
agreement for the purposes of:

     (a)  adding to the covenants of any or all parties, provided that the board
          of directors of each of SMTC Canada, SMTC Nova Scotia and SMTC shall
          be of the good faith opinion that such additions will not be
          prejudicial to the rights or interests of the holders of the
          Exchangeable Shares;

     (b)  making such amendments or modifications not inconsistent with this
          agreement as may be necessary or desirable with respect to matters or
          questions which, in the good faith opinion of the board of directors
          of each of SMTC Canada, SMTC Nova Scotia and SMTC, it may be expedient
          to make, provided that each such board of directors shall be of the
          good faith opinion that such amendments or modifications will not be
          prejudicial to the rights or interests of the holders of the
          Exchangeable Shares; or

     (c)  making such changes or corrections which, on the advice of counsel to
          SMTC Canada, SMTC Nova Scotia and SMTC, are required for the purpose
          of curing or correcting any ambiguity or defect or inconsistent
          provision or clerical omission or mistake or manifest error, provided
          that the board of directors of each

                                      -11-
<PAGE>

          of SMTC Canada, SMTC Nova Scotia and SMTC shall be of the good faith
          opinion that such changes or corrections will not be prejudicial to
          the rights or interests of the holders of the Exchangeable Shares.

4.4  Meeting to Consider Amendments

     SMTC Canada, at the request of SMTC or SMTC Nova Scotia, shall call a
meeting or meetings of the holders of the Exchangeable Shares for the purpose of
considering any proposed amendment or modification requiring approval pursuant
to Section 4.2. Any such meeting or meetings shall be called and held in
accordance with the bylaws of SMTC Canada, the Exchangeable Share Provisions and
all applicable laws.

4.5  Changes in Capital of SMTC and SMTC Canada

     At all times after the occurrence of any event contemplated pursuant to
Sections 2.7 and 2.8 or otherwise, as a result of which either the shares of
SMTC Common Stock or the Exchangeable Shares or both are in any way changed,
this agreement shall forthwith be amended and modified as necessary in order
that it shall apply with full force and effect, with the appropriate changes, to
all new securities into which shares of SMTC Common Stock or the Exchangeable
Shares or both are so changed and the parties hereto shall execute and deliver
an agreement in writing giving effect to and evidencing such necessary
amendments and modifications.

4.6  Amendments Only in Writing

     No amendment to or modification or waiver of any of the provisions of this
agreement otherwise permitted hereunder shall be effective unless made in
writing and signed by all of the parties hereto.

4.7  Assignment

     This agreement shall not be assignable by any party hereto.

4.8  Time

     Time shall be of the essence of this agreement.

4.9  Governing Law

     This agreement and the rights and obligations of the parties hereto shall
be governed by and construed and interpreted in accordance with the laws of the
Province of Ontario and the federal laws of Canada applicable therein.

4.10 Severability

     If any term or other provision of this agreement is invalid, illegal or
incapable of being enforced by any rule or law, or public policy, all other
conditions and provisions of this agreement shall nevertheless remain in full
force and effect so long as the economic or legal

                                      -12-
<PAGE>

substance of the transactions contemplated hereby is not affected in any manner
materially adverse to any party. Upon such determination that any term or other
provision is invalid, illegal or incapable of being enforced, the parties hereto
shall negotiate in good faith to modify this agreement so as to effect the
original intent of the parties as closely as possible in an acceptable manner to
the end that the transactions contemplated hereby are fulfilled to the fullest
extent possible.

4.11 Enurement

     This agreement shall be binding upon and enure to the benefit of the
parties hereto and their respective successors and assigns.

4.12 Notices to Parties

     All notices and other communications hereunder shall be in writing and
shall be given and shall be deemed to have been duly given at the time of
receipt, if delivered in person or sent by facsimile transmission on a Business
Day at the place of receipt (or, if given on a non-Business Day at the place of
receipt, shall be deemed to have been duly given on the next succeeding Business
Day at such place) to the parties as follows:

(a)   if to SMTC:

      SMTC Corporation
      635 Hood Road
      Markham, Ontario
      Canada L3R 4N6

      Attention:  Richard J. Smith, C.A.
                  Vice-President, Finance and Administration
      Fax:        (905) 479-5326

      with a copy to:

      Ropes & Gray
      One International Place
      Boston, Massachusetts
      U.S.A. 02110-2624

      Attention:  Alfred Rose
      Fax:        (617) 951-7050

                                      -13-
<PAGE>

     (b)  if to SMTC Canada or SMTC Nova Scotia:

          SMTC Manufacturing Corporation of Canada
          635 Hood Road
          Markham, Ontario
          Canada L3R 4N6

          Attention:  Richard J. Smith, C.A.
                      Vice-President, Finance and Administration
          Fax:        (905) 479-5326

          with a copy to:

          McMillan Binch
          Suite 3800, South Tower
          Royal Bank Plaza
          Toronto, Ontario
          Canada M5J 2J7

          Attention:  Stephen C.E. Rigby
          Fax:        (416) 865-7048

or to such other address as a party may have furnished to the others in writing
in accordance herewith, except that notices of change of address shall be
effective only upon receipt.

4.13 Counterparts

     This agreement may be executed in counterparts, each of which shall be
deemed an original, and all of which taken together shall constitute one and the
same document.

4.14 Attornment

     Each of SMTC and SMTC Nova Scotia agrees that any action or proceeding
arising out of or relating to this agreement may be instituted in the courts of
Ontario, waives any objection which it may have now or hereafter to the venue of
any such action or proceeding, irrevocably submits to the jurisdiction of the
said courts in any such action or proceeding, agrees to be bound by any judgment
of the said courts and agrees not to seek, and hereby waives, any review of the
merits of any such judgment by the court of any other jurisdiction and hereby
appoints SMTC Canada at its registered office in the Province of Ontario as its
attorney for service of process.

                                      -14-
<PAGE>

     IN WITNESS WHEREOF the parties hereto have caused this agreement to be duly
executed as of the date first above written.



                                 SMTC CORPORATION


                                 By: /s/ Paul Walker
                                     ------------------------------
                                     Name:  Paul Walker
                                     Title: President


                                 SMTC NOVA SCOTIA COMPANY


                                 By: /s/ Paul Walker
                                     ------------------------------
                                     Name:  Paul Walker
                                     Title: President


                                 SMTC MANUFACTURING CORPORATION OF CANADA


                                 By: /s/ Paul Walker
                                     ------------------------------
                                     Name:  Paul Walker
                                     Title: President

                                      -15-