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                                                                     EXHIBIT 4.2

                          REGISTRATION RIGHTS AGREEMENT

     REGISTRATION RIGHTS AGREEMENT dated as of October 15, 1999 (this
"Agreement") by and between Boston Private Financial Holdings, Inc., a
Massachusetts corporation ("BPFH") and the several persons signatory hereto
(each a "Stockholder" and collectively the "Stockholders").

     BPFH, Boston Private Financial Planning, Inc., a Massachusetts corporation
and wholly-owned subsidiary of BPFH, RINET Company, Inc., a Massachusetts
corporation, and the Stockholders are parties to an Agreement and Plan of Merger
dated as of July 22, 1999 (the "Plan of Merger"), pursuant to which, among other
things, the Stockholders will have the right to receive shares (the "Shares") of
common stock, $1.00 par value per share ("Common Stock"), of BPFH, in exchange
for all the shares of Class A Common Stock (as defined in the Plan of Merger)
and Class B Common Stock (as defined in the Plan of Merger) of RINET Company,
Inc., a Massachusetts corporation, all as more fully set forth in the Plan of
Merger.

     This Agreement is being entered into to set forth certain rights and
obligations of BPFH and the Stockholders with respect to the registration under
the Securities Act of 1933, as amended, or any successor federal statute and the
rules and regulations of the Securities and Exchange Commission (the "SEC")
thereunder, and in the case of any reference to any such statute, rule or
regulation, any successor section (the "Securities Act"), of the offer and sale
of the Shares by the Stockholders, all as more fully set forth in this
Agreement.

     In consideration of the foregoing and the respective covenants and
agreements set forth herein, and for other good and valuable consideration, the
parties hereto agree as follows:

     Section 1.     EFFECTIVENESS OF REGISTRATION RIGHTS. The registration
rights granted pursuant to Sections 2 and 3 hereof shall be effective as of the
closing of the transactions contemplated by the Plan of Merger.

     Section 2.     DEMAND REGISTRATION.

          2.1       NOTICE AND REGISTRATION. At any time after January 1, 2000
and from time to time thereafter, subject to the terms and conditions set forth
herein, upon written notice by two or more Stockholders (as to any such notice
and the related registration of Covered Shares, "Requesting Stockholders")
requesting that BPFH effect the registration under the Securities Act of not
less than 100,000 Covered Shares in the aggregate held by them, which notice
shall specify the intended method or methods of disposition of such Covered
Shares, BPFH will promptly give written notice (the "BPFH Notice") of such
requested registration to all other Stockholders then holding Covered Shares.
Any such Stockholder who wishes to have Covered Shares included in such
registration shall give written notice delivered to BPFH within 20 days after
the date of the BPFH Notice indicating such intent, upon which such Stockholder
will become a Requesting Stockholder with respect to the related notice and
registration. BPFH will use its reasonable best efforts to promptly effect the
registration under the Securities Act of the Covered Shares requested to be
registered by the Requesting Stockholders on Form


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S-3 (or any successor form substantially equivalent thereto) or, if such forms
are not then available to BPFH, such other appropriate form as BPFH may elect,
for disposition in accordance with the intended method or methods of disposition
stated in such request, PROVIDED that:

                    (a)  BPFH shall not be required to effect more than one (1)
registration of Covered Shares pursuant to this Section 2 during any consecutive
twelve month period. No registration of Covered Shares under Section 2 which
shall not become effective shall be deemed to be a registration for the purposes
of this sentence;

                    (b)  in the event that as to any request for registration
pursuant to this Section 2, Requesting Stockholders request the registration of
more than an amount of Covered Shares equal to twenty percent (20%) of the total
aggregate number of shares of BPFH Common Stock received by the Stockholders
pursuant to the Plan of Merger (the "Initial Shares"), BPFH may in its sole
discretion by written notice to each Requesting Stockholder reduce the number of
Covered Shares of each Requesting Stockholder to be registered in response to
such request, pro rata based on the number of Covered Shares requested to be
registered, to the extent necessary to reduce the aggregate number of Covered
Shares to be registered in response to such request to not less than an amount
of Covered Shares equal to twenty percent (20%) of the Initial Shares;

                    (c)  if BPFH shall have previously effected a registration,
other than registrations incidental to any securities issued in connection with
mergers, acquisitions, exchange offers, dividend reinvestment plans or stock
option or other benefit plans, under the Securities Act with respect to Common
Stock (including without limitation, any registration of Common Stock pursuant
to the Westfield Merger Agreement (as defined in Section 7.3 hereof)), BPFH
shall not be required to effect a registration pursuant to this Section 2 until
a period of 120 days shall have elapsed from the effective date of the most
recent such previous registration;

                    (d)  if upon receipt of a registration request pursuant to
this Section 2 BPFH is engaged or has firm plans to engage within 90 days of the
time of the request in a registered public offering of securities (a "BPFH
Offering"), then BPFH may at its option direct that such request be delayed for
a period not in excess of 90 days from the commencement of such public offering,
PROVIDED, however, that in any twelve month period BPFH may only one time in the
aggregate exercise its right to either so delay a request or impose a
Transaction Blackout;

                    (e)  if, at the time of any request to register Covered
Shares pursuant to this Section 2 or after such request but prior to the filing
of the related registration statement, BPFH's Chief Executive Officer determines
in good faith that the filing of a registration statement would require the
disclosure of material information which BPFH has a bona fide business purpose
for preserving as confidential, BPFH may at its option direct that such request
be delayed until the earlier of (A) the date upon which such material
information is disclosed to the public or ceases to be material or (B) 90 days
after the date of the decision to so delay; PROVIDED, however, that BPFH may not
so delay a registration pursuant to this Section 2.1(e) or suspend sales
pursuant to a Transaction Blackout for more than 90 days in the aggregate during
any twelve consecutive month period without the approval of the Board of
Directors of BPFH; and


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                    (f)  the Stockholders' right to request registration
pursuant to this Section 2 shall terminate in the event that at anytime after
the seventh anniversary hereof BPFH offers to register all Covered Shares held
by Stockholders for sale in an underwritten public offering and either (i) no
Stockholder requests to have Covered Shares included in such offering or (ii)
such underwritten public offering is consummated and results in the opportunity
to sell all Covered Shares requested by Stockholders to be included in such
offering.

          2.2       REGISTRATION EXPENSES. BPFH (as between BPFH and the
Requesting Stockholders) shall bear all Registration Expenses in connection with
any registration pursuant to this Section 2, other than underwriting discounts
and commissions, stock transfer taxes or fees and expenses of legal, tax and
other counsel or advisors to the Requesting Stockholders, except that the
expenses of one counsel for the Requesting Stockholders are included in the
definition of Registration Expenses unless such registration is effected in
connection with registration of shares issued in the Westfield Merger, in which
case the Requesting Stockholders shall be represented jointly by a single
counsel representing the holders of shares issued in connection with the
Westfield Merger.

          2.3       THIRD PERSON AND COMPANY SHARES. BPFH shall have the right
to cause the registration of securities for sale for the account of any person
in any registration of Covered Shares requested pursuant to this Section 2;
PROVIDED, however, that in no event shall such inclusion result in the number of
Covered Shares to be included in such registration being reduced below an amount
of Covered Shares equal to twenty percent (20%) of the Initial Shares or such
lesser number of Covered Shares sought to be included therein by Requesting
Stockholders.

          2.4       FINANCIAL INFORMATION. Notwithstanding anything to the
contrary herein, in connection with any registration provided for in this
Section 2, BPFH will not be obligated to furnish any financial statements other
than the audited financial statements customarily prepared at the end of its
fiscal year and unaudited financial information customarily required by the SEC
under the Securities Act and the Securities Exchange Act of 1934, as amended or
that may be required by any successor federal statutes. In the event that
additional financial statements or other financial information or schedules is
so required and is not readily available to BPFH, then BPFH shall be entitled to
defer the performance of its obligations under this Section 2 until such time as
such additional financial statements will not be so required or will be readily
available, or, at its option, BPFH shall at the request of Requesting
Stockholders prepare such additional financial statements or other information,
and the costs and expenses of BPFH in connection therewith, including salary and
related overhead expenses of employees of BPFH and any subsidiary or affiliate
of BPFH for time expended by such employees in the preparation of such financial
or other information, will be reimbursed to BPFH by the Requesting Stockholders
so requesting such preparation.

          2.5       ADDITIONAL DEMAND RIGHT. In the event that in any two
consecutive twelve month periods BPFH delays a registration pursuant to Section
2.1(e) or suspends sales pursuant to Transaction Blackouts for 90 or more days
in the aggregate during each of such consecutive twelve month periods, upon a
written request by Requesting Stockholders pursuant to Section 2.1 hereof BPFH
will use its reasonable best efforts to effect within six months of such request
a registration for an underwritten public offering pursuant and subject to the
terms and conditions of Section 2 and this Agreement, provided that as applied
to any registration pursuant to this Section 2.5 (i) the references to "an
amount


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of Covered Shares equal to twenty percent (20%) of the Initial Shares" contained
in Section 2.1(b) and in Section 2.3 shall be deemed to be references to "an
amount of Covered Shares equal to forty percent (40%) of the Initial Shares,"
(ii) no registration pursuant to this Section 2.5 shall be counted toward the
limitation on registrations provided in Section 2.1(a) and (iii) Section 2.1(d)
and Section 4.3(a) as it applies to Transaction Blackouts shall be inapplicable.

     Section 3.     PIGGYBACK REGISTRATION.

          3.1       NOTICE AND REGISTRATION. If at any time or from time to time
after the effectiveness of this Agreement BPFH proposes to register any Common
Stock ("Other Securities") for public sale under the Securities Act (whether
proposed to be offered for sale by BPFH or any other person) in an underwritten
public offering and on a form and in a manner which would permit registration of
Covered Shares for sale to the public under the Securities Act, it will give
written notice to the each Stockholder of its intention to do so, and upon the
written request of Stockholders (as to any such notice and the related
registration of Covered Shares, "Requesting Stockholders") delivered to BPFH
within 10 business days after the giving of any such notice (which request shall
specify the Covered Shares intended to be disposed of by the Requesting
Stockholder) requesting that BPFH include in such registered underwritten public
offering any number of Covered Shares owned by such Requesting Stockholders,
BPFH will use its reasonable best efforts to effect, in connection with the
registration of the Other Securities, the registration under the Securities Act
of all Covered Shares which BPFH has been so requested to register by such
Requesting Stockholders, to the extent required to permit the disposition of
Covered Shares so to be registered; PROVIDED that:

                    (a)  if, at any time after giving such written notice of its
intention to register any Other Securities and prior to the effective date of
the registration statement filed in connection with such registration, BPFH
shall determine for any reason not to register the Other Securities, BPFH shall
give written notice of such determination to the Requesting Stockholders and
BPFH may, at its election, be relieved of its obligation to register such
Covered Shares in connection with the registration of such Other Securities (but
not from its obligation to pay Registration Expenses to the extent incurred in
connection therewith as provided in Section 3.2), without prejudice, however, to
the rights (if any) of the Requesting Stockholders immediately to request that
such registration be effected as a registration under Section 2 to the extent
that such request would comply with all of the terms and conditions of Section
2;

                    (b)  if BPFH shall have been advised in writing (with a copy
to each Requesting Stockholder) by a nationally recognized independent
investment banking firm selected by BPFH (who is then acting as the managing
underwriter for any such offering) that, in such firm's opinion, the inclusion
of all or any portion of the Covered Shares then intended to be disposed of by
Requesting Stockholders in the proposed registration at that time would
adversely affect in a significant manner the registration and offering of the
Other Securities, the number of Covered Shares requested to be included in the
proposed registration shall be reduced on a pro rata basis among all Requesting
Stockholders based on the number of such Covered Shares requested to be included
by each such Requesting Stockholder or, as the case may be, shall all be
excluded from such registration in their entirety, to the extent necessary as
determined by such investment banking firm to prevent the proposed registration
of Other Securities from being so effected; PROVIDED, however, that if as a
result of the provisions of this Section 3.1(b), BPFH is unable to include in
such registration all of the Covered Shares requested by the Requesting


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Stockholders for inclusion in such registration, BPFH shall so notify each
Requesting Stockholder and give each Requesting Stockholder the right to
withdraw all Covered Shares requested by the Requesting Stockholder for
inclusion in such registration from such registration by notice to BPFH within 5
days after receipt of BPFH's notice;

                    (c)  BPFH shall not be required to effect any registration
of Covered Shares under this Section 3 incidental to the registration of any of
its securities in connection with mergers, acquisitions, exchange offers,
subscription offers, dividend reinvestment plans or stock option or other
employee benefit or similar plans; and

                    (d)  the Stockholders have requested that at least 100,000
Covered Shares, in the aggregate, be included in such registration of Other
Securities; provided, however, that Requesting Shareholders may request
registration of less than 100,000 Covered Shares in connection with registration
rights granted pursuant to the Westfield Merger Agreement provided that the
number of shares of BPFH Common Stock to be so requested total 100,000 or more.

          3.2       REGISTRATION EXPENSES. BPFH (as between BPFH and the
Requesting Stockholders) shall bear all Registration Expenses in connection with
any registration pursuant to this Section 3, other than underwriting discounts
and commissions, stock transfer taxes or fees and expenses of legal, tax and
other counsel or advisors to the Requesting Stockholders, except that the
expenses of one counsel for the Requesting Stockholders are included in the
definition of Registration Expenses. In no event, however, shall the Company be
required to pay for the expenses of more than one counsel in connection with any
registration pursuant to this Section 3.

     Section 4.     REGISTRATION PROCEDURES.

          4.1       REGISTRATION AND QUALIFICATION. If and whenever BPFH is
required to use its reasonable best efforts to effect the registration of any
Covered Shares under the Securities Act as provided in Section 2 or Section 3,
BPFH will as promptly as is practicable:

                    (a)  in the case of a request pursuant to Section 2,
prepare, file and use its reasonable best efforts to cause to become effective a
registration statement under the Securities Act regarding the Covered Shares to
be offered on such appropriate registration form of the SEC as shall be selected
by BPFH;

                    (b)  in the case of a request pursuant to Section 2, prepare
and file with the SEC such amendments and supplements to such registration
statement and the prospectus used in connection therewith as may be necessary to
keep such registration statement effective and to comply with the provisions of
the Securities Act with respect to the disposition of all Covered Shares until
the later of (i) such time as all of such Covered Shares have been disposed of
in accordance with the intended methods of disposition by the Requesting
Stockholders set forth in such registration statement (but in no event beyond
the date that a subsequent registration statement filed pursuant to a request
under Section 2 becomes effective) or (ii) the expiration of the time when a
prospectus relating to any sale made within the period contemplated by phrase
(i) of this paragraph is required to be delivered under the Securities Act;


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                    (c)  furnish to each Requesting Stockholder and to any
underwriter of such Covered Shares such number of conformed copies of such
registration statement and of each such amendment and supplement thereto (in
each case including all exhibits), such number of copies of the prospectus or
prospectus supplement included in such registration statement (including each
preliminary prospectus and any summary prospectus) and, in conformity with the
requirements of the Securities Act, such documents incorporated by reference in
such registration statement or prospectus as the Requesting Stockholder or such
underwriter may reasonably request in order to facilitate the public sale or
other disposition of the Covered Shares;

                    (d)  use its reasonable best efforts to register or qualify
all Covered Shares covered by such registration statement under such other
securities or blue sky laws of such United States jurisdictions as the
Requesting Stockholders or any underwriter of such Covered Shares shall
reasonably request, except that BPFH shall not for any such purpose be required
to qualify generally to do business as a foreign corporation in any jurisdiction
where it is not so qualified, or to subject itself to taxation in any such
jurisdiction or to consent to general service of process in any such
jurisdiction;

                    (e)  immediately notify each Requesting Stockholder (i) of
the time any registration statement filed hereunder becomes effective or when
any amendment or supplement or prospectus forming a part of such registration
statement has been filed, (ii) of any request by the SEC for an amendment or
supplement to such registration statement or prospectus or for additional
information, (iii) after BPFH shall have received notice or otherwise obtained
knowledge thereof, of the issuance of any order by the SEC suspending the
effectiveness of such registration statement or any amendment thereto or of the
initiation or threatening of any proceeding for that purpose (and BPFH will use
its reasonable best efforts to prevent the issuance of any such stop order or to
obtain its withdrawal promptly if such stop order should be issued) and (iv) at
any time when a prospectus relating to a registration pursuant to Section 2 or
Section 3 is required to be delivered under the Securities Act, of the happening
of an event as a result of which the prospectus included in such registration
statement, as then in effect, includes an untrue statement of a material fact or
omits to state any material fact required to be stated therein or necessary to
make the statements therein, in light of the circumstances under which they were
made, not misleading, and, subject to Section 4.3, at the request of any
Requesting Stockholder prepare and furnish to such Requesting Stockholder a
reasonable number of copies of a supplement to or an amendment of such
prospectus as may be necessary so that, as thereafter delivered to the
purchasers of such Covered Shares, such prospectus shall not include an untrue
statement of a material fact or omit to state a material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances under which they are made, not misleading; PROVIDED that the time
period set forth in Section 4.1(b)(ii) hereof shall be extended for a number of
days equal to the number of days in the period from and including the date BPFH
gave the notice required by this Section 4.1(e) through the date when BPFH
delivers such supplement or amendment.

BPFH may require each Requesting Stockholder to furnish BPFH with such
information regarding such Requesting Stockholder and the distribution of such
securities as BPFH may from time to time reasonably request in writing or as
shall be required by law or by the SEC or the National Association of Securities
Dealers, Inc. ("NASD") or any underwriter in connection with any registration.


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Each Stockholder hereby agrees to promptly notify BPFH of any changes in the
information provided to BPFH; and

                    (f)  BPFH agrees in the case of an underwritten offering
under Section 2 or Section 3 hereof to refrain, without the consent of the
managing underwriter, for a period from 15 days before the effective date of the
registration statement until 90 days after such effective date, from publicly
selling, offering to sell, publicly selling any option for the sale of any
common equity or securities convertible into common equity other than pursuant
to BPFH employee equity plans.

          4.2       UNDERWRITING.

                    (a)  If a registration pursuant to Section 3 involves an
underwritten offering, BPFH shall have the right to select the managing
underwriter. If a registration pursuant to Section 2 involves an underwritten
offering, BPFH shall consult with the Requesting Stockholders as to the
selection of the managing underwriter(s) for such underwritten offering. BPFH
shall have the right after such consultation to select the managing
underwriter(s) for any such underwritten public offering subject to the approval
of Requesting Stockholders holding a majority of the Covered Shares requested to
be registered in such underwritten offering, which approval may not be
unreasonably withheld. Stockholders agree not to discuss the possible engagement
of any managing underwriter with such underwriter without the prior written
consent of BPFH.

                    (b)  If requested by the underwriters for any underwritten
offering of Covered Shares pursuant to a registration requested hereunder, BPFH
will enter into an underwriting agreement with such underwriters for such
offering, such agreement to contain such representations and warranties by BPFH
and such other terms and provisions as are customarily contained in underwriting
agreements with respect to secondary distributions, including, without
limitation, indemnities and contribution to the effect and to the extent
provided in Section 6 and the provision to such underwriters and the Requesting
Stockholders of opinions of counsel and accountants' letters to the effect and
to the extent provided in Section 4.2(c). The representations and warranties by,
and the other agreements on the part of, BPFH to and for the benefit of such
underwriters shall also be made to and for the benefit of Requesting
Stockholders. As a condition to each Requesting Stockholder's rights under
Section 2 and Section 3, such Requesting Stockholder shall become a party to any
such underwriting agreement, such agreement to contain such representations and
warranties by such Requesting Stockholders and such other terms and provisions
as the underwriters may reasonably request, including without limitation,
indemnities and contributions to the effect and to the extent provided in
Section 6.

                    (c)  In the case of an underwritten offering of Covered
Shares, BPFH shall use its reasonable best efforts to obtain and furnish copies
to each Requesting Stockholder of (i) an opinion of counsel for BPFH which is
also addressed or confirmed to the Requesting Stockholders, dated the date of
the closing under the underwriting agreement, and (ii) a "cold comfort" letter
signed by the independent public accountants who have certified BPFH's financial
statements included in such registration statement, each covering substantially
the same matters with respect to such registration statement (and the prospectus
included therein) and, in the case of such accountants' letter, with respect to
events subsequent to the date of such financial statements, as are customarily
covered in opinions of issuer's counsel and in accountants' letters in
underwritten public offerings of securities.


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                    (d)  In the event of any registration pursuant to Section 3
hereof, BPFH may require Requesting Stockholders requesting that Covered Shares
be registered pursuant to Section 3 to participate in such underwriting on the
same terms and conditions, and pursuant to the same Underwriting Agreement as
shall be applicable to persons seeking the Other Securities to be sold through
underwriters under such registration.

          4.3       BLACKOUT PERIODS.

                    (a)  At any time when a registration statement effected
pursuant to Section 2 or 3 hereunder relating to Covered Shares is effective,
upon written notice from BPFH to the Requesting Stockholders that either:

                         (i)  BPFH has firm plans to engage within 90 days in a
     BPFH Offering and has been advised in writing (with a copy to the
     Requesting Stockholders) by a nationally recognized independent investment
     banking firm selected by BPFH that, in such firm's opinion, the Requesting
     Stockholders' sale of Covered Shares pursuant to the registration statement
     would adversely affect in a significant manner such immediately planned
     BPFH Offering (a "Transaction Blackout"); or

                         (ii) BPFH determines, based on the good faith advice of
     outside corporate counsel to BPFH, that the Requesting Stockholders' sale
     of Covered Shares pursuant to the registration statement would require
     disclosure of material information which, in the good faith judgment of the
     Chief Executive Officer of BPFH, BPFH has a bona fide business purpose for
     preserving as confidential (an "Information Blackout"),

the Requesting Stockholders shall suspend sales of Covered Shares pursuant to
such registration statement until the earlier of:

          (X)  (i)  in the case of a Transaction Blackout, the earliest of (A)
     90 days after the effectiveness of the registration statement relating to
     such BPFH Offering, (B) the termination of any "blackout" period required
     by the underwriters to be applicable to BPFH or the Stockholders, if any,
     in connection with such BPFH Offering or (C) promptly after abandonment of
     such BPFH Offering, or (ii) in the case of an Information Blackout, the
     earlier of (A) the date upon which such material information is disclosed
     to the public or ceases to be material or (B) 90 days after the date of
     suspension of sales; or

          (Y)  such time as BPFH notifies the Requesting Stockholders that sales
     pursuant to such registration statement may be resumed (the number of days
     from such suspension of sales of the Requesting Stockholders until the day
     when such sales may be resumed hereunder is hereinafter called a "Sales
     Blackout Period");

PROVIDED that BPFH may not impose a Transaction Blackout during any underwritten
public offering.

                    (b)  If there is a Transaction Blackout or an Information
Blackout, the time period set forth in Section 4.1(b)(ii) shall be extended for
a number of days equal to the number of days in the Sales Blackout Period.


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          4.4       LISTING. In connection with the registration of any offering
of Covered Shares pursuant to this Agreement, BPFH agrees to use its reasonable
best efforts, at BPFH's expense, to effect the listing of such shares on any
securities exchange on which any shares of the Common Stock are then listed.

     Section 5.     PREPARATION; REASONABLE INVESTIGATION. In connection with
the preparation and filing of each registration statement registering Covered
Shares under the Securities Act, BPFH will give each Requesting Stockholder and
the underwriters, if any, and their respective counsel and accountants, such
reasonable and customary access to its books and records and such opportunities
to discuss the business of BPFH with its officers and other appropriate
personnel and the independent public accountants who have certified its
financial statements as shall be reasonably necessary to conduct a reasonable
investigation within the meaning of the Securities Act.

     Section 6.     INDEMNIFICATION AND CONTRIBUTION.

                    (a)  In the event of any registration of any Covered Shares
hereunder, BPFH will enter into customary indemnification arrangements to
indemnify and hold harmless the Requesting Stockholders, each person who
participates as an underwriter in the offering or sale of such securities, each
officer and director of each underwriter, and each person, if any, who controls
any such underwriter within the meaning of the Securities Act against any
losses, claims, damages, liabilities or expenses to which such person may be
subject under the Securities Act or otherwise insofar as such losses, claims,
damages, liabilities or expenses (or actions or proceedings in respect thereof)
arise out of are based upon (i) any untrue statement or alleged untrue statement
of any material fact contained in any registration statement under which such
securities were registered under the Securities Act, any preliminary prospectus
or final prospectus included therein, any amendment or supplement thereto or any
document incorporated by reference therein or (ii) any omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, and BPFH will reimburse
each such person for any legal or other expenses reasonably incurred by such
person in connection with investigating or defending any such loss, claim,
damage or liability (or action or proceeding in respect thereof); PROVIDED that
BPFH shall not be liable in any such case to the extent that any such loss,
claim, damage or liability (or action or proceeding in respect thereof) or
expense arises out of or is based upon an untrue statement or alleged untrue
statement or omission or alleged omission made in such registration statement,
any such preliminary prospectus or final prospectus, amendment or supplement (A)
in reliance upon and in conformity with written information furnished to BPFH by
any Requesting Stockholder or such underwriter specifically for use in the
preparation thereof or (B) and corrected in any prospectus or amendment or
supplement thereto that was delivered to the Requesting Stockholder or
underwriter prior to the sale or sales of Covered Shares in question. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of the Requesting Stockholders or any such person and shall
survive the transfer of such securities by the Requesting Stockholder. BPFH also
shall agree to provide for contribution as shall reasonably be requested by the
Requesting Stockholders or any underwriters in circumstances where such
indemnity is held unenforceable.

                    (b)  Each Requesting Stockholder, by virtue of exercising
its registration rights hereunder, agrees and undertakes to enter into customary
indemnification arrangements to indemnify and


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hold harmless (in the same manner and to the same extent as set forth in Section
6(a)) BPFH, each director of BPFH, each officer of BPFH who shall sign such
registration statement, each person who participates as an underwriter or a
selling stockholder in the offering or sale of such securities, each officer and
director of each underwriter and selling stockholder, and each person, if any,
who controls BPFH or any such underwriter or selling stockholder within the
meaning of the Securities Act, with respect to any statement in or omission from
such registration statement, any preliminary prospectus or final prospectus
included therein, or any amendment or supplement thereto, if such statement or
omission was made in reliance upon and in conformity with written information
furnished by the Requesting Stockholder to BPFH specifically for inclusion in
such registration statement or prospectus. Such indemnity shall remain in full
force and effect regardless of any investigation made by or on behalf of BPFH or
any such director, officer or controlling person and shall survive the transfer
of the registered securities by the Requesting Stockholder. Each Requesting
Stockholder also shall agree to provide for contribution as shall reasonably be
requested by BPFH or any underwriters or selling stockholder in circumstances
where such indemnity is held unenforceable.

                    (c)  Indemnification and contribution similar to that
specified in the preceding subdivisions of this Section 6 (with appropriate
modifications) shall be given by BPFH and each Requesting Stockholder with
respect to any required registration or other qualification of such Covered
Shares under any federal or state law or regulation of governmental authority
other than the Securities Act.

     Section 7.     BENEFITS AND TERMINATION OF REGISTRATION RIGHTS.

          7.1       EXERCISE. Registration rights granted hereunder may only be
exercised by the Stockholders or their permitted assigns.

          7.2       TERMINATION. The registration rights of any Stockholder
hereunder shall cease to apply to Covered Shares held by such Stockholder when
(a) a registration statement with respect to the sale of such Covered Shares
shall have become effective under the Securities Act and such shares shall have
been disposed of in accordance with such registration statement or (b) all such
Covered Shares are eligible to be sold pursuant to Rule 144 under the Securities
Act (or any successor provision) during any two (2) successive three (3) month
periods.

          7.3       OTHER AGREEMENTS. BPFH is party to that certain Agreement
and Plan of Merger dated August 13, 1997 by and among BPFH, Boston Private
Investment Management, Inc., Westfield Capital Management Company, Inc.
("Westfield"), and certain stockholders of Westfield named therein (the
"Westfield Merger Agreement"), that certain Stock Purchase Agreement, dated
December 2, 1996, by and between BPFH and the investors named therein and that
certain Asset Purchase Agreement, dated as of June 16, 1995, by and among BPFH,
Boston Private Bank & Trust Company, Cunningham, Henderson and Papin
Incorporated and the stockholders of Cunningham, Henderson and Papin
Incorporated, each of which agreements provide certain registration rights with
respect to shares of Common Stock held by certain parties thereto (the "Other
Registration Rights"). The rights of the Stockholders hereunder and the
obligations of BPFH hereunder are expressly subject to and, to the extent
inconsistent therewith, limited by such Other Registration Rights.


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<PAGE>   11


     Section 8. CERTAIN DEFINITIONS.

          8.1   REGISTRATION EXPENSES. As used in this Agreement, the term
"Registration Expenses" means all expenses incident to BPFH's performance of or
compliance with the registration requirements set forth in this Agreement,
including, without limitation, the following: (i) the fees, disbursements and
expenses of BPFH's counsel and accountants in connection with the registration
of Covered Shares to be disposed of under the Securities Act; (ii) all expenses
in connection with the preparation, printing and filing of the registration
statement, any preliminary prospectus or final prospectus, any other offering
document and amendments and supplements thereto and the mailing and delivering
of copies thereof to the underwriters and dealers; (iii) the cost of printing
and producing any agreements among underwriters, underwriting agreements, and
blue sky or legal investment memoranda, any selling agreements and any
amendments thereto or other documents in connection with the offering, sale or
delivery of Covered Shares to be disposed of; (iv) all expenses in connection
with the qualification of Covered Shares to be disposed of for offering and sale
under state securities laws, including the fees and disbursements of counsel for
the underwriters in connection with such qualification and in connection with
any blue sky and legal investment surveys; (v) the filing fees incident to
securing any required review by the NASD of the terms of the sale of Covered
Shares to be disposed of; (vi) the costs of preparing stock certificates; (vii)
the costs and charges of BPFH's transfer agent and registrar; and (viii) the
reasonable fees and disbursements of one counsel for the Requesting
Stockholders.

          8.2       COVERED SHARES. "Covered Shares" means the Shares and any
stock dividends or distributions made on the Shares from BPFH (including,
without limitation, as a result of a stock split) or any securities which become
convertible into or exchanged for BPFH shares in the event there is a sale of
all or substantially all of the assets of BPFH, or a merger or a reorganization
of BPFH.

     Section 9.     LEGEND. Each certificate representing the Covered Shares
shall be stamped or otherwise imprinted with a legend substantially in the
following form:

          "The securities represented by this certificate have not been
          registered under the Securities Act of 1933, as amended, and may not
          be transferred or otherwise disposed of unless they have been
          registered under said Act or an exemption from registration is
          available."

The foregoing legend shall be removed at such time as the restrictions referred
to therein cease to be applicable.

     Section 10.    TERMINATION. This Agreement shall terminate on the earlier
of the date that no Stockholder owns any Covered Shares or the date that all
Covered Shares held by all Stockholders are freely saleable without restriction
under the Securities Act.

     Section 11.    MISCELLANEOUS.

          11.1      ASSIGNMENT. This Agreement shall be binding upon and inure
to the benefit of and be enforceable by the parties hereto and (a) with respect
to BPFH, its successors and assigns and (b) with respect to the Stockholders,
its successors and permitted assigns. No Stockholder may assign any of its
rights and obligations hereunder without the prior written consent of BPFH,
PROVIDED that a


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<PAGE>   12


Stockholder may assign its rights and obligations hereunder to any trust,
limited partnership or other estate planning vehicle the sole beneficiaries or
equity holders of which shall be such Stockholder and/or one or more of a
spouse, parent, sibling, child or grandchild of such Stockholder or any
charitable trust or foundation or, without compensation, to any charitable trust
or foundation.

          11.2      GOVERNING LAW; JURISDICTION. This Agreement shall be
construed, performed and enforced in accordance with, and governed by, the laws
of the Commonwealth of Massachusetts (without giving effect to the principles of
conflicts of laws thereof).

          11.3      SEVERABILITY. In the event that any part of this Agreement
is declared by any court or other judicial or administrative body to be null,
void or unenforceable, said provision shall survive to the extent it is not so
declared, and all of the other provisions of this Agreement shall remain in full
force and effect.

          11.4      NOTICES. All notices, requests, demands and other
communications hereunder shall be in writing and shall be sent by hand delivery,
receipt acknowledged, or by telegram, telex or facsimile transmission, to the
respective parties at the following addresses:

     If to BPFH:

              Ten Post Office Square
              Boston, Massachusetts 02109

              Attention: Timothy L. Vaill
              Facsimile: (617) 912-4557

     with a copy to

              Goodwin, Procter & Hoar,  LLP
              Exchange Place
              52 State Street
              Boston, Massachusetts 02109

              Attention: Richard E. Floor, P.C. or William P. Mayer, Esq.
              Facsimile: (617) 523-1231

     If to the Stockholder, at the address of record reflected upon the books of
BPFH,

     with a copy to

              Nutter, McClennan & Fish, LLP
              One International Place
              Boston, MA 02109

              Attention:  Michael Mooney, Esq. or Gene A. Blumenreich, Esq.
              Facsimile: (617) 973-9748


                                     Page 12
<PAGE>   13



     Any party may change its address or facsimile number for receiving notice
by written notice given to the other party. All notices, requests, demands and
other communications hereunder shall be deemed to have been duly given as of the
earlier of (a) the date received or (b) the date receipt is acknowledged.

          11.5      RULE 144 INFORMATION. With a view to making available to the
Stockholders the benefits of Rule 144 promulgated under the Securities Act
("Rule 144") and any other rule or regulation of the SEC that may at any time
permit a Stockholder to sell Covered Shares to the public without registration,
BPFH agrees to:

                    (a)  use its reasonable best efforts to file with the SEC
all reports and other documents required of BPFH to be filed pursuant to the
Securities Act or the Securities Exchange Act of 1934; and

                    (b)  furnish to any Stockholder forthwith upon request (1) a
written statement by BPFH as to its compliance with the reporting requirements
of paragraph (c)(1) Rule 144, (2) a copy of the most recent annual or quarterly
report of BPFH and (3) at the Stockholder's expense, such other public,
non-confidential information as may be reasonably requested in availing any
Stockholder of any rule or regulation of the SEC which permits the selling of
any such securities without registration or pursuant to such form.

          11.6      CONFIDENTIALITY. Stockholder agrees to treat as confidential
and not to disclose to any other person any information provided to Stockholder
by BPFH pursuant to this Agreement that BPFH notifies Stockholder is
confidential.

          11.7      AMENDMENTS; WAIVERS. This Agreement may be amended or
modified, and any of the terms, covenants or conditions hereof may be waived,
only by a written instrument executed by the parties hereto, or in the case of a
waiver, by the party waiving compliance. Any waiver by any party of any
condition, or of the breach of any provision, term or covenant contained in this
Agreement, in any one or more instances, shall not be deemed to be nor construed
as a furthering or continuing waiver of any such condition, or of the breach of
any other provision, term or covenant of this Agreement.

          11.8      SECTION AND PARAGRAPH HEADINGS. The section and paragraph
headings in this Agreement are for reference purposes only and shall not affect
the meaning or interpretation of this Agreement.

          11.9      COUNTERPARTS. This Agreement may be executed in
counterparts, each of which shall be deemed an original, but all of which shall
constitute the same instrument.


                                     Page 13
<PAGE>   14


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

                                          BOSTON PRIVATE FINANCIAL
                                          HOLDINGS, INC.

                                          By: /s/ Timothy L. Vaill
                                              -------------------------------
                                              Name: Timothy L. Vaill
                                              Title: Chairman, President and CEO


STOCKHOLDERS:

By: /s/ Richard N. Thielen
    -----------------------------------
    Name: Richard N. Thielen

By: /s/ Patrick B. Maraghy
    -----------------------------------
    Name: Patrick B. Maraghy

By: /s/ Valerio Iannolfo
    -----------------------------------
    Name: Valerio Iannolfo

By: /s/ Mary Ann Rodrigue
    -----------------------------------
    Name: Mary Ann Rodrigue


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