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                                                                     Exhibit 2.1

                     PLAN OF REORGANIZATION AND ACQUISITION

                     PURSUANT TO SECTION 26B OF CHAPTER 172
                      OF THE GENERAL LAWS OF MASSACHUSETTS


         This Plan of Reorganization and Acquisition (the "Plan") is dated as of
July 29, 1997, and made between Medford Savings Bank, a Massachusetts guaranty
(stock) savings bank (the "Bank"), and Medford Bancorp, Inc., a Massachusetts
corporation ("Bancorp").

         The Bank is a stock savings bank, duly organized and validly existing
under the laws of the Commonwealth of Massachusetts, with its principal office
at 29 High Street, Medford, Massachusetts 02155. As of the date hereof, the
authorized capital stock of the Bank consists of (1) 15,000,000 shares of common
stock, par value $0.50 per share (the "Bank Common Stock"), of which 4,541,148
shares are issued and outstanding, 200,000 shares are reserved for issuance
under the Bank's 1993 Stock Option Plan (as the same may be renamed from time to
time), and, 736,000 shares are reserved for issuance under the Bank's 1986 Stock
Option Plan (the 1993 Stock Option Plan and the 1986 Stock Option Plan are
collectively referred to herein as the "Stock Option Plans"), and (2) 5,000,000
shares of preferred stock, par value $0.50 per share, none of which shares are
issued and outstanding.

         Bancorp is a corporation, duly organized and validly existing under the
laws of the Commonwealth of Massachusetts, with its principal office at 29 High
Street Medford, Massachusetts 02155. The articles of organization of Bancorp at
the Effective Time (as defined herein) will provide for authorized capital stock
consisting of 15,000,000 shares of common stock, par value $0.50 per share (the
"Bancorp Common Stock"), and 5,000,000 shares of preferred stock, par value
$0.50 per share. As of the date hereof, there are 100 shares of Bancorp Common
Stock issued and outstanding, all of which are held by the Bank.

         The Bank and Bancorp have agreed that Bancorp will acquire all of the
issued and outstanding shares of Bank Common Stock (together with associated
preferred stock purchase rights) in exchange for shares of Bancorp Common Stock
(together with associated preferred stock purchase rights) pursuant to the
provisions of Section 26B of Chapter 172 of the General Laws of Massachusetts
and of this Plan. The Plan has been adopted and approved by a vote of a majority
of all the members of the Board of Directors of the Bank, and by a vote of a
majority of all the members of the Board of Directors of Bancorp. The officers
of the Bank and of Bancorp whose respective signatures appear below have been
duly authorized to execute and deliver this Plan.

         Now, THEREFORE, in consideration of these premises, the Bank and
Bancorp agree as follows:
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SECTION 1 - APPROVAL AND FILING OF PLAN

         1.1. The Plan shall be submitted for approval by the holders of Bank
Common Stock at a meeting to be called and held in accordance with the
applicable provisions of law. Notice of such meeting shall be published at least
once a week for two successive weeks in a newspaper of general circulation in
the County of Suffolk, Commonwealth of Massachusetts. Both of said publications
shall be at least fifteen days prior to the date of the meeting.

         1.2. Upon approval of the Plan by the affirmative vote of the holders
of 66 2/3% of the outstanding shares of Bank Common Stock as required by law, 
the Bank and Bancorp shall submit the Plan to the Commissioner of Banks of the
Commonwealth of Massachusetts (the "Bank Commissioner") for his approval and
filing in accordance with the provisions of Section 26B of Chapter 172 of the
General Laws of Massachusetts. The Plan shall be accompanied by such
certificates of the respective officers of the Bank and Bancorp as may be
required by law and a written request from the Bank that the Plan not be filed
by the Bank Commissioner until such future time as the Bank Commissioner shall
have received from the Bank and Bancorp the written notice described in
Subsection 2.1.

         1.3. If the requisite approval of the Plan is obtained at the meeting
of holders of Bank Common Stock referred to in Subsection 1.1, thereafter and
until the Effective Time, as hereinafter defined, the Bank shall issue
certificates for Bank Common Stock, whether upon transfer or otherwise, only if
such certificates bear a legend indicating that the Plan has been approved and
that shares of Bank Common Stock evidenced by such certificates are subject to
acquisition by Bancorp pursuant to the Plan.

SECTION 2 - DEFINITION OF EFFECTIVE TIME

         2.1. The Plan shall become effective at 12:01 A.M. on the first
business day following the date on which the Bank and Bancorp advise the Bank
Commissioner in writing (i) that all the conditions precedent to the Plan
becoming effective specified in Section 5 have been satisfied and (ii) that the
Plan has not been abandoned by the Bank or Bancorp in accordance with the
provisions of Section 6, or at such other date and time as is specified in such
written notice to the Bank Commissioner. Such time is hereafter called the
"Effective Time."

SECTION 3 - ACTIONS AT THE EFFECTIVE TIME

         3.1. At the Effective Time, Bancorp shall, without any further action
on its part or on the part of the holders of Bank Common Stock, automatically
and by operation of law acquire and become the owner for all purposes of all the
then issued and outstanding shares of Bank Common Stock (together with
associated preferred stock purchase rights) and shall be entitled to have issued
to it by the Bank a certificate or certificates representing such shares.
Thereafter, Bancorp shall have full and exclusive power to vote such shares of
Bank Common Stock, to receive dividends thereon and to exercise all rights of an
owner thereof.


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         3.2. At the Effective Time, the shares of Bancorp Common Stock which
are outstanding immediately prior to the Effective Time shall be canceled.

         3.3. At the Effective Time, the holders of the then issued and
outstanding shares of Bank Common Stock (together with associated preferred
stock purchase rights) shall, without any further action on their part or on the
part of Bancorp, automatically and by operation of law cease to own such shares
and shall instead become owners of one share of Bancorp Common Stock (together
with associated preferred stock purchase rights) for each share of Bank Common
Stock held by them immediately prior to the Effective Time. Thereafter, such
persons shall have full and exclusive power to vote such shares of Bancorp
Common Stock, to receive dividends thereon, except as otherwise provided herein,
and to exercise all rights of an owner thereof.

         3.4. At the Effective Time, all previously issued and outstanding
certificates representing shares of Bank Common Stock (the "Old Certificates")
shall automatically and by operation of law cease to represent shares of Bank
Common Stock or any interest therein and each Old Certificate shall instead
represent the ownership by the holder thereof of an equal number of shares of
Bancorp Common Stock. No holder of an Old Certificate shall be entitled to vote
the shares of Bank Common Stock formerly represented by such certificate, or to
receive dividends thereon, or to exercise any other rights of ownership in
respect thereof.

         3.5. Notwithstanding any of the foregoing, any Dissenting Stockholder,
as defined in Subsection 8.1, shall have such rights as are provided by
Subsection 8.2 and by the laws of the Commonwealth of Massachusetts.

SECTION 4 - ACTIONS AFTER THE EFFECTIVE TIME

         As soon as practicable and in any event not more than thirty days after
the Effective Time:

         4.1. Bancorp shall deliver to the transfer agent for the Bank and
Bancorp (the "Transfer Agent"), as agent for the then holders of the Old
Certificates (other than Old Certificates representing shares of Bank Common
Stock as to which dissenters' appraisal rights shall have been exercised), a
certificate or certificates for the aggregate number of shares of Bancorp Common
Stock (the "New Certificates"), to which said holders shall be entitled. Each
such holder may surrender his Old Certificate to the Transfer Agent and receive
in exchange therefor a New Certificate for an equal number of shares of Bancorp
Common Stock. However, holders of Old Certificates need not surrender Old
Certificates to the transfer Agent in exchange for a New Certificate. The
Transfer Agent shall treat Old Certificates as representing for all purposes an
equal number of shares of Bancorp Common Stock.

         4.2. Bancorp may publish a notice to the holders of all Old
Certificates, specifying the Effective Time of the Plan and notifying such
holders that they may present their Old Certificates to the Transfer Agent for
exchange for a New Certificate representing an equal number of shares of Bancorp
Common Stock. Such notice may likewise be given by mail to such holders at their
addresses on the Bank's records.

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SECTION 5 - CONDITIONS PRECEDENT

         The Plan and the acquisition provided for herein shall not become
effective unless all of the following first shall have occurred:

         5.1. The Plan shall have been approved by the affirmative vote of the
holders of two-thirds of the outstanding Bank Common Stock at a meeting of such
stockholders called for such purpose.

         5.2. The Plan shall have been approved by the Bank Commissioner and a
copy of the Plan with his approval endorsed thereon shall have been filed in his
office, all as provided in Section 26B of Chapter 172 of the General Laws of
Massachusetts.

         5.3. Any approval, consent, or waiver required by the Board of
Governors of the Federal Reserve System shall have been received, and any
waiting period imposed by applicable law shall have expired.

         5.4. The Bank shall have received a favorable opinion from its counsel,
satisfactory in form and substance to the Bank, with respect to the federal
income tax consequences of the Plan and the acquisition contemplated thereby.

         5.5. The shares of Bancorp Common Stock (together with associated
preferred stock purchase rights) to be issued to the holders of Bank Common
Stock pursuant to the Plan shall have been registered or qualified for such
issuance to the extent required under all applicable state securities laws.

         5.6. The Bank and Bancorp shall have obtained all other consents,
permissions and approvals and taken all actions required by law or agreement, or
deemed necessary by the Bank or Bancorp, prior to the consummation of the
acquisition provided for by the Plan and to Bancorp's having and exercising all
rights of ownership with respect to all of the outstanding shares of Bank Common
Stock acquired by it thereunder.

SECTION 6 - ABANDONMENT OF PLAN

         6.1. The Plan may be abandoned by either the Bank or Bancorp at any
time before the Effective Time in the event that:

                  (a) Necessary regulatory approvals cannot be obtained, or the
conditions or obligations associated with such regulatory approvals make
consummation of the acquisition contemplated by the Plan inadvisable in the
opinion of Bank or Bancorp;

                  (b) The number of shares of Bank Common Stock owned by
Dissenting Stockholders, as defined in Subsection 8.1, shall make consummation
of the acquisition contemplated by the Plan inadvisable in the opinion of the
Bank or Bancorp;

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                  (c) Any action, suit, proceeding or claim has been instituted,
made or threatened relating to the Plan which shall make consummation of the
acquisition contemplated by the Plan inadvisable in the opinion of the Bank or
Bancorp; or

                  (d) For any other reason consummation of the acquisition
contemplated by the Plan is inadvisable in the opinion of the Bank or Bancorp.

         Such abandonment shall be effected by written notice by either the Bank
or Bancorp to the other of them, and shall be authorized or approved by the
Board of Directors of the party giving such notice. Upon the giving of such
notice, the Plan shall be terminated and there shall be no liability hereunder
or on account of such on the part of the Bank or Bancorp or the Directors,
officers, employees, agents or stockholders of either of them. In the event of
abandonment of the Plan, the Bank shall pay the fees and expenses incurred by
itself and Bancorp in connection with the Plan and the proposed acquisition. If
either party hereto gives written notice of termination to the other party
pursuant to this section, the party giving such written notice shall
simultaneously furnish a copy thereof to the Bank Commissioner.

SECTION 7 - AMENDMENT OF PLAN

         7.1. The Plan may be amended or modified at any time by mutual
agreement of the Boards of Directors of Bancorp and the Bank (i) prior to its
approval by the stockholders of the Bank, in any respect, and (ii) subsequent to
such approval, in any respect, provided that the Bank Commissioner shall approve
of such amendment or modification.

SECTION 8 - RIGHTS OF DISSENTING STOCKHOLDERS

         8.1. "Dissenting Stockholders" shall mean those holders of Bank Common
Stock who file with the Bank before the taking of the vote on the Plan, written
objection to the Plan, pursuant to Section 86 of Chapter 156B of the General
Laws of Massachusetts, stating that they intend to demand payment for their
shares of Bank Common Stock if the Plan is consummated and whose shares are not
voted in favor of the Plan.

         8.2. Dissenting Stockholders who comply with the provisions of Sections
86 to 98, inclusive, of Chapter 156B of the General Laws of Massachusetts and
all other applicable provisions of law shall be entitled to receive from the
Bank payment of the fair value of their shares of Bank Common Stock upon
surrender by such holders of the certificates which previously represented
shares of Bank Common Stock. Certificates so obtained by the Bank, upon payment
of the fair value of such shares as provided by law, shall be canceled. Shares
of Bancorp Common Stock, to which Dissenting Stockholders would have been
entitled had they not dissented, shall be deemed to constitute authorized but
unissued shares of Bancorp Common Stock and may be sold or otherwise disposed of
by Bancorp at the discretion of, and on such terms as may be fixed by, its Board
of Directors.


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SECTION 9 - STOCK OPTIONS

         By voting in favor of the Plan and by consummation of the acquisition
contemplated by the Plan, Bancorp shall have approved adoption by Bancorp of the
Stock Option Plans of the Bank as the Stock Option Plans of Bancorp and shall
have agreed to issue Bancorp Common Stock in lieu of Bank Common Stock pursuant
to stock options then outstanding under the Stock Option Plans. As of the
Effective Time, the unexercised portion of the options outstanding under the
existing Stock Option Plans shall be assumed by Bancorp and thereafter shall be
exercisable only for shares of Bancorp Common Stock, with each such option being
exercisable for a number of shares of Bancorp Common Stock equal to the number
of shares of Bank Common Stock that were available thereunder immediately prior
to the Effective Time, and with no change in the exercise price or any other
term or condition of such option. Bancorp and the Bank shall make appropriate
amendments to the Stock Option Plans to reflect the adoption of such plans as
the Stock Option Plans of Bancorp without adverse effect upon the options
outstanding under the Stock Option Plans.

SECTION 10 - GOVERNING LAW

         The Plan shall take effect as a sealed instrument and shall be governed
by and construed in accordance with the laws of the Commonwealth of
Massachusetts.

SECTION 11 - COUNTERPARTS

         The Plan may be executed in several identical counterparts, each of
which when executed and delivered by the parties hereto shall be an original,
but all of which together shall constitute a single instrument. In making proof
of the Plan, it shall not be necessary to produce or account for more than one
such counterpart.


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                                MEDFORD SAVINGS BANK


                                By:    /s/ Arthur H. Meehan
                                      ----------------------------------------
                                      Arthur H. Meehan
                                      Chairman, President and Chief Executive
                                      Officer
ATTEST:

/s/ Eugene R. Murray
- - - ------------------------------
Eugene R. Murray
Clerk

                                MEDFORD BANCORP, INC.


                                By:    /s/ Arthur H. Meehan
                                      ----------------------------------------
                                      Arthur H. Meehan
                                      Chairman, President and Chief Executive
                                      Officer
ATTEST:

/s/ Eugene R. Murray
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Eugene R. Murray
Clerk

        I hereby approve this Plan of Reorganization and Acquisition.

             October 30, 1997                /s/ Thomas J. Curry
             ----------------                -------------------
                   Date                      Thomas J. Curry
                                             Commissioner of Banks       
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