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                                                                    Exhibit 10.5



                           CHANGE OF CONTROL AGREEMENT


     AGREEMENT by and between United Asset Management Corporation, a Delaware
corporation (the "COMPANY") and James F. Orr III (the "EXECUTIVE"), dated as of
the 15th day of May, 2000.

     The Board of Directors of the Company (the "BOARD"), has determined that it
is in the best interests of the Company and its shareholders to assure that the
Company will have the continued dedication of the Executive, notwithstanding the
possibility, threat or occurrence of a Change of Control (as defined below) of
the Company. The Board believes it is imperative to diminish the inevitable
distraction of the Executive by virtue of the personal uncertainties and risks
created by a pending or threatened Change of Control and to encourage the
Executive's full attention and dedication to the Company currently and in the
event of any threatened or pending Change of Control, and to provide the
Executive with compensation and benefits arrangements upon a Change of Control
which ensure that the compensation and benefits expectations of the Executive
will be satisfied and which are competitive with those of other corporations.
Therefore, in order to accomplish these objectives, the Board has caused the
Company to enter into this Agreement.

     NOW, THEREFORE, IT IS HEREBY AGREED AS FOLLOWS:

     1.   CERTAIN DEFINITIONS. (a) The "EFFECTIVE DATE" shall mean the first
date during the Change of Control Period (as defined in Section 1(b)) on which a
Change of Control (as defined in Section 2) occurs. Anything in this Agreement
to the contrary notwithstanding, if a Change of Control occurs and if the
Executive's employment with the Company is terminated prior to the date on which
the Change of Control occurs, and if it is reasonably demonstrated by the
Executive that such termination of employment (i) was at the request of a third
party who has taken steps reasonably calculated to effect a Change of Control or
(ii) otherwise arose in connection with or anticipation of a Change of Control,
then for all purposes of this Agreement the "EFFECTIVE DATE" shall mean the date
immediately prior to the date of such termination of employment.

     (b)  The "CHANGE OF CONTROL PERIOD" shall mean the period commencing on the
date hereof and ending on the second anniversary of the date hereof; provided,
however, that commencing on the date one year after the date hereof, and on each
annual anniversary of such date (such date and each annual anniversary thereof
shall be hereinafter referred to as the "Renewal Date"), unless previously
terminated, the Change of Control Period shall be automatically extended so as
to terminate two years from such Renewal Date, unless at least 60 days prior to
the Renewal Date the Company shall give notice to the Executive that the Change
of Control Period shall not be so extended.


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     2.   CHANGE OF CONTROL. For the purpose of this Agreement, a "CHANGE OF
CONTROL" shall mean:

     (a)  The acquisition by any individual, entity or group (within the meaning
of Section 13(d)(3) or 14(d)(2) of the Securities Exchange Act of 1934, as
amended (the "EXCHANGE ACT")) (a "PERSON") of beneficial ownership (within the
meaning of Rule 13d-3 promulgated under the Exchange Act) of 30% or more of
either (i) the then outstanding shares of common stock of the Company (the
"OUTSTANDING COMPANY COMMON STOCK") or (ii) the combined voting power of the
then outstanding voting securities of the Company entitled to vote generally in
the election of directors (the "OUTSTANDING COMPANY VOTING SECURITIES");
provided, however, that for purposes of this subsection (a), the following
acquisitions shall not constitute a Change of Control: (i) any acquisition
directly from the Company, (ii) any acquisition by the Company, (iii) any
acquisition by any employee benefit plan (or related trust) sponsored or
maintained by the Company or any corporation controlled by the Company or (iv)
any acquisition by any corporation pursuant to a transaction which complies with
clauses (i), (ii) and (iii) of subsection (c) of this Section 2; or

     (b)  Individuals who, as of the date hereof, constitute the Board (the
"INCUMBENT BOARD") cease for any reason to constitute at least a majority of the
Board; provided, however, that any individual becoming a director subsequent to
the date hereof whose election, or nomination for election by the Company's
shareholders, was approved by a vote of at least a majority of the directors
then comprising the Incumbent Board shall be considered as though such
individual were a member of the Incumbent Board, but excluding, for this
purpose, any such individual whose initial assumption of office occurs as a
result of an actual or threatened election contest with respect to the election
or removal of directors or other actual or threatened solicitation of proxies or
consents by or on behalf of a Person other than the Board; or

     (c)  Consummation of a reorganization, merger or consolidation or sale or
other disposition of all or substantially all of the assets of the Company or
the acquisition of assets or stock of another corporation (a "BUSINESS
COMBINATION"), in each case, unless, following such Business Combination, (i)
all or substantially all of the individuals and entities who were the beneficial
owners, respectively, of the Outstanding Company Common Stock and Outstanding
Company Voting Securities immediately prior to such Business Combination
beneficially own, directly or indirectly, more than 50% of, respectively, the
then outstanding shares of common stock and the combined voting power of the
then outstanding voting securities entitled to vote generally in the election of
directors, as the case may be, of the corporation resulting from such Business
Combination (including, without limitation, a corporation which as a result of
such transaction owns the Company or all or substantially all of the Company's
assets either directly or through one or more subsidiaries) in substantially the
same proportions as their ownership, immediately prior to such Business
Combination of the Outstanding Company Common Stock and Outstanding Company
Voting Securities, as the case may be, (ii) no Person (excluding any corporation
resulting from such Business Combination or any employee benefit plan (or
related trust) of the Company or such corporation resulting from such Business


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Combination) beneficially owns, directly or indirectly, 30% or more of,
respectively, the then outstanding shares of common stock of the corporation
resulting from such Business Combination or the combined voting power of the
then outstanding voting securities of such corporation except to the extent that
such ownership existed prior to the Business Combination, and (iii) at least a
majority of the members of the board of directors of the corporation resulting
from such Business Combination were members of the Incumbent Board at the time
of the execution of the initial agreement, or of the action of the Board,
providing for such Business Combination; or

     (d)  Approval by the shareholders of the Company of a complete liquidation
or dissolution of the Company.

     3.   PROTECTED PERIOD; EFFECT ON PRIOR AGREEMENT. The Company hereby agrees
to continue the Executive in its employ, and the Executive hereby agrees to
remain in the employ of the Company subject to the terms and conditions of this
Agreement, for the period commencing on the Effective Date and ending on the
second anniversary of such date (the "PROTECTED PERIOD"). The effectiveness of
the Employment Agreement, dated as of May 15, 2000, between the Company and the
Executive (the "PRIOR AGREEMENT") shall be suspended during the Protected
Period, except as specifically set forth herein; provided that if the
Executive's employment is not terminated on or before the last day of the
Protected Period, then the Prior Agreement shall be effective during the period,
if any, from the end of the Protected Period through the end of the Employment
Period (as defined in the Prior Agreement).

     4.   TERMS OF EMPLOYMENT. (a) POSITION AND DUTIES. (i) During the Protected
Period, (A) the Executive's position (including status, offices, titles and
reporting requirements), authority, duties and responsibilities shall be at
least commensurate in all material respects with the most significant of those
held, exercised and assigned at any time during the 120-day period immediately
preceding the Effective Date and (B) the Executive's services shall be performed
at the location where the Executive was employed immediately preceding the
Effective Date or any office or location less than 35 miles from such location.

     (ii) During the Protected Period, and excluding any periods of vacation and
sick leave to which the Executive is entitled, the Executive agrees to devote
reasonable attention and time during normal business hours to the business and
affairs of the Company and, to the extent necessary to discharge the
responsibilities assigned to the Executive hereunder, to use the Executive's
reasonable best efforts to perform faithfully and efficiently such
responsibilities. During the Protected Period it shall not be a violation of
this Agreement for the Executive to (A) serve on corporate, civic or charitable
boards or committees, (B) deliver lectures, fulfill speaking engagements or
teach at educational institutions, and (C) manage personal investments, so long
as such activities are reasonable and do not significantly interfere with the
performance of the Executive's responsibilities as an employee of the Company in
accordance with this Agreement. It is expressly understood and agreed that to
the extent that any such activities have been conducted by the Executive prior
to the Effective Date, the continued conduct of such activities


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(or the conduct of activities similar in nature and scope thereto) subsequent to
the Effective Date shall not thereafter be deemed to interfere with the
performance of the Executive's responsibilities to the Company.

     (b)  COMPENSATION. (i) BASE SALARY. During the Protected Period, the
Executive shall receive an annual base salary ("ANNUAL BASE SALARY"), which
shall be paid at a monthly rate, at least equal to twelve times the highest
monthly base salary paid or payable, including any base salary which has been
earned but deferred, to the Executive by the Company in respect of the
twelve-month period immediately preceding the month in which the Effective Date
occurs. During the Protected Period, the Annual Base Salary shall be reviewed no
more than 12 months after the last salary increase awarded to the Executive
prior to the Effective Date and thereafter at least annually. Any increase in
Annual Base Salary shall not serve to limit or reduce any other obligation to
the Executive under this Agreement. Annual Base Salary shall not be reduced
after any such increase and the term Annual Base Salary as utilized in this
Agreement shall refer to Annual Base Salary as so increased. As used in this
Agreement, the term "affiliated companies" shall include any company controlled
by, controlling or under common control with the Company.

     (ii) ANNUAL BONUS. In addition to Annual Base Salary, the Executive shall
be awarded, for each fiscal year ending during the Protected Period, an annual
bonus (the "ANNUAL BONUS") in cash at least equal to 100% of the Annual Base
Salary (the "RECENT ANNUAL BONUS"). Each such Annual Bonus shall be paid no
later than the end of the third month of the fiscal year next following the
fiscal year for which the Annual Bonus is awarded, unless the Executive shall
elect to defer the receipt of such Annual Bonus.

     (iii) INCENTIVE, SAVINGS AND RETIREMENT PLANS. During the Protected Period,
the Executive shall be entitled to participate in all incentive, savings and
retirement plans, practices, policies and programs applicable generally to other
peer executives of the Company, but in no event shall such plans, practices,
policies and programs provide the Executive with incentive opportunities
(measured with respect to both regular and special incentive opportunities, to
the extent, if any, that such distinction is applicable), savings opportunities
and retirement benefit opportunities, in each case, less favorable, in the
aggregate, than the most favorable of those provided by the Company for the
Executive under such plans, practices, policies and programs as in effect at any
time during the 120-day period immediately preceding the Effective Date or if
more favorable to the Executive, those provided generally at any time after the
Effective Date to other peer executives of the Company. Without limiting the
generality of the foregoing, the Executive shall be entitled to be granted the
Options as defined in Section 3(c) of the Prior Agreement, to the extent not
previous granted.

     (iv) WELFARE BENEFIT PLANS. During the Protected Period, the Executive
and/or the Executive's family, as the case may be, shall be eligible for
participation in and shall receive all benefits under welfare benefit plans,
practices, policies and programs provided by the Company (including, without
limitation, medical, prescription, dental, disability, employee life,


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group life, accidental death and travel accident insurance plans and programs)
to the extent applicable generally to other peer executives of the Company, but
in no event shall such plans, practices, policies and programs provide the
Executive with benefits which are less favorable, in the aggregate, than the
most favorable of such plans, practices, policies and programs in effect for the
Executive at any time during the 120-day period immediately preceding the
Effective Date or, if more favorable to the Executive, those provided generally
at any time after the Effective Date to other peer executives of the Company.

     (v)  EXPENSES. During the Protected Period, the Executive shall be entitled
to receive prompt reimbursement for all reasonable expenses incurred by the
Executive in accordance with the most favorable policies, practices and
procedures of the Company in effect for the Executive at any time during the
120-day period immediately preceding the Effective Date or, if more favorable to
the Executive, as in effect generally at any time thereafter with respect to
other peer executives of the Company. In addition, the Executive shall be
entitled to receive the expense reimbursements provided for in Section 3(e)(i)
of the Prior Agreement (the "RELOCATION EXPENSES"), to the extent not previously
paid.

     (vi) FRINGE BENEFITS. During the Protected Period, the Executive shall be
entitled to fringe benefits, including, without limitation, parking and payment
of club dues, in accordance with the most favorable plans, practices, programs
and policies of the Company in effect for the Executive at any time during the
120-day period immediately preceding the Effective Date or, if more favorable to
the Executive, as in effect generally at any time thereafter with respect to
other peer executives of the Company.

     (vii) OFFICE AND SUPPORT STAFF. During the Protected Period, the Executive
shall be entitled to an office or offices of a size and with furnishings and
other appointments, and to personal secretarial and other assistance, at least
equal to the most favorable of the foregoing provided to the Executive by the
Company at any time during the 120-day period immediately preceding the
Effective Date or, if more favorable to the Executive, as provided generally at
any time thereafter with respect to other peer executives of the Company.

     (viii) VACATION. During the Protected Period, the Executive shall be
entitled to paid vacation in accordance with the most favorable plans, policies,
programs and practices of the Company as in effect for the Executive at any time
during the 120-day period immediately preceding the Effective Date or, if more
favorable to the Executive, as in effect generally at any time thereafter with
respect to other peer executives of the Company.

     5.   TERMINATION OF EMPLOYMENT. (a) DEATH OR DISABILITY. The Executive's
employment shall terminate automatically upon the Executive's death during the
Protected Period. If the Company determines in good faith that the Disability of
the Executive has occurred during the Protected Period (pursuant to the
definition of Disability set forth below), it may give to the Executive written
notice in accordance with Section 12(b) of this Agreement of its intention to
terminate the Executive's employment. In such event, the Executive's


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employment with the Company shall terminate effective on the 30th day after
receipt of such notice by the Executive (the "DISABILITY EFFECTIVE DATE"),
provided that, within the 30 days after such receipt, the Executive shall not
have returned to full-time performance of the Executive's duties. For purposes
of this Agreement, "DISABILITY" shall mean the absence of the Executive from the
Executive's duties with the Company on a full-time basis for 180 consecutive
business days as a result of incapacity due to mental or physical illness which
is determined to be total and permanent by a physician selected by the Company
or its insurers and acceptable to the Executive or the Executive's legal
representative.

     (b)  CAUSE. The Company may terminate the Executive's employment during the
Protected Period for Cause. For purposes of this Agreement, "CAUSE" shall mean:

     (i)  the willful and continued failure of the Executive to perform
substantially the Executive's duties with the Company or one of its affiliates
(other than any such failure resulting from incapacity due to physical or mental
illness, or which occurs after the Executive gives a valid Notice of Termination
for Good Reason), after a written demand for substantial performance is
delivered to the Executive by the Board of the Company which specifically
identifies the manner in which the Board believes that the Executive has not
substantially performed the Executive's duties, or

     (ii) the willful engaging by the Executive in illegal conduct or gross
misconduct which is materially and demonstrably injurious to the Company.

     For purposes of this provision, no act or failure to act, on the part of
the Executive, shall be considered "willful" unless it is done, or omitted to be
done, by the Executive in bad faith or without reasonable belief that the
Executive's action or omission was in the best interests of the Company. Any
act, or failure to act, based upon authority given pursuant to a resolution duly
adopted by the Board or based upon the advice of counsel for the Company shall
be conclusively presumed to be done, or omitted to be done, by the Executive in
good faith and in the best interests of the Company. The cessation of employment
of the Executive shall not be deemed to be for Cause unless and until there
shall have been delivered to the Executive a copy of a resolution duly adopted
by the affirmative vote of not less than three-quarters of the entire membership
of the Board at a meeting of the Board called and held for such purpose (after
reasonable notice is provided to the Executive and the Executive is given an
opportunity, together with counsel, to be heard before the Board), finding that,
in the good faith opinion of the Board, the Executive is guilty of the conduct
described in subparagraph (i) or (ii) above, and specifying the particulars
thereof in detail.

     (c)  GOOD REASON. The Executive's employment may be terminated by the
Executive for Good Reason or without Good Reason. For purposes of this
Agreement, "GOOD REASON" shall mean:

     (i)  the assignment to the Executive of any duties inconsistent in any
respect with the Executive's position (including status, offices, titles and
reporting requirements),


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authority, duties or responsibilities as contemplated by Section 4(a) of this
Agreement, or any other action by the Company which results in a diminution in
such position, authority, duties or responsibilities, unless, in the case of the
first such assignment or action to occur, it is remedied by the Company promptly
after receipt of notice thereof from the Executive;

     (ii) any failure by the Company to comply with any of the provisions of
Section 4(b) of this Agreement, unless, in the case of the first such failure to
occur, it is remedied by the Company promptly after receipt of notice thereof
from the Executive;

     (iii) the Company's requiring the Executive to be based at any office or
location other than as provided in Section 4(a)(i)(B) hereof or the Company's
requiring the Executive to travel on Company business to a substantially greater
extent than required immediately prior to the Effective Date;

     (iv) any purported termination by the Company of the Executive's employment
otherwise than as expressly permitted by this Agreement; or

     (v)  any failure by the Company to comply with and satisfy Section 11(c) of
this Agreement.

     For purposes of this Section 5(c), any good faith determination of "Good
Reason" made by the Executive shall be conclusive.

     (d)  NOTICE OF TERMINATION. Any termination by the Company for Cause, or by
the Executive for Good Reason or without Good Reason, shall be communicated by
Notice of Termination to the other party hereto given in accordance with Section
12(b) of this Agreement. For purposes of this Agreement, a "NOTICE OF
TERMINATION" means a written notice which (i) indicates the specific termination
provision in this Agreement relied upon, (ii) to the extent applicable, sets
forth in reasonable detail the facts and circumstances claimed to provide a
basis for termination of the Executive's employment under the provision so
indicated, and (iii) if the Date of Termination (as defined below) is other than
the date of receipt of such notice, specifies the termination date (which date
shall be not more than thirty days after the giving of such notice). The failure
by the Executive or the Company to set forth in the Notice of Termination any
fact or circumstance which contributes to a showing of Good Reason or Cause
shall not waive any right of the Executive or the Company, respectively,
hereunder or preclude the Executive or the Company, respectively, from asserting
such fact or circumstance in enforcing the Executive's or the Company's rights
hereunder.

     (e)  DATE OF TERMINATION. "DATE OF TERMINATION" means (i) if the
Executive's employment is terminated by the Company for Cause, or by the
Executive for Good Reason or without Good Reason, the date of receipt of the
Notice of Termination or any later date specified therein, as the case may be,
(ii) if the Executive's employment is terminated by the Company other than for
Cause or Disability, the Date of Termination shall be the date on which the


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Company notifies the Executive of such termination, and (iii) if the Executive's
employment is terminated by reason of death or Disability, the Date of
Termination shall be the date of death of the Executive or the Disability
Effective Date, as the case may be.

     6.   OBLIGATIONS OF THE COMPANY UPON TERMINATION. (a) GOOD REASON; OTHER
THAN FOR CAUSE, DEATH OR Disability. If, during the Protected Period, the
Company shall terminate the Executive's employment other than for Cause or
Disability or the Executive shall terminate employment for Good Reason:

     (i)  the Company shall pay to the Executive in a lump sum in cash within 30
days after the Date of Termination the aggregate of the following amounts:

          A.   the sum of (1) the Executive's Annual Base Salary through the
     Date of Termination to the extent not theretofore paid, (2) the excess (if
     any) of (A) the product of (x) the higher of (I) the Recent Annual Bonus
     and (II) the Annual Bonus paid or payable (whether in one or more
     installments), including any bonus or portion thereof which has been earned
     but deferred (and annualized for any fiscal year consisting of less than
     twelve full months or during which the Executive was employed for less than
     twelve full months), with respect to the most recently completed fiscal
     year during the Protected Period, if any (such higher amount being referred
     to as the "HIGHEST ANNUAL BONUS") and (y) a fraction, the numerator of
     which is the number of days in the current fiscal year that the Executive
     was employed by the Company through the Date of Termination, and the
     denominator of which is 365, over (B) the amounts of any installments of
     the Annual Bonus with respect to the fiscal year in which the Date of
     Termination occurs that have already been paid to the Executive, and (3)
     any compensation previously deferred by the Executive (together with any
     accrued interest or earnings thereon), any Relocation Expenses and any
     accrued vacation pay, in each case to the extent not theretofore paid (the
     sum of the amounts described in clauses (1), (2), and (3) shall be
     hereinafter referred to as the "ACCRUED OBLIGATIONS"); and

          B.   the amount equal to the product of (1) three and (2) the sum of
     (x) the Executive's Annual Base Salary and (y) the Highest Annual Bonus;
     and

          C.   an amount equal to three times the aggregate employer
     contributions made to the Executive's accounts in the Company's qualified
     and nonqualified defined contribution pension plans with respect to the
     most recent plan year that ended before the Effective Date or, if higher,
     any subsequent plan year, plus the amount of any accrued but unvested
     portion of the Executive's accounts in such plans that the Executive
     forfeits;


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     (ii) for three years after the Executive's Date of Termination, or such
longer period as may be provided by the terms of the appropriate plan, program,
practice or policy, the Company shall continue health and dental benefits to the
Executive and/or the Executive's family at least equal to those which would have
been provided to them in accordance with the plans, programs, practices and
policies described in Section 4(b)(iv) of this Agreement if the Executive's
employment had not been terminated or, if more favorable to the Executive, as in
effect generally at any time thereafter with respect to other peer executives of
the Company and their families, provided, however, that if the Executive becomes
reemployed with another employer and is eligible to receive health or dental
benefits under another employer provided plan, the benefits described herein
shall be secondary to those provided under such other plan during such
applicable period of eligibility; and

     (iii) to the extent not theretofore paid or provided, the Company shall
timely pay or provide to the Executive any other amounts or benefits required to
be paid or provided or which the Executive is eligible to receive under any
plan, program, policy or practice or contract or agreement of the Company and
its affiliated companies (such other amounts and benefits shall be hereinafter
referred to as the "OTHER BENEFITS").

     (b)  DEATH. If the Executive's employment is terminated by reason of the
Executive's death during the Protected Period, this Agreement shall terminate
without further obligations to the Executive's legal representatives under this
Agreement, other than for payment of Accrued Obligations and the timely payment
or provision of Other Benefits. Accrued Obligations shall be paid to the
Executive's estate or beneficiary, as applicable, in a lump sum in cash within
30 days of the Date of Termination. With respect to the provision of Other
Benefits, the term Other Benefits as utilized in this Section 6(b) shall
include, without limitation, and the Executive's estate and/or beneficiaries
shall be entitled to receive, benefits at least equal to the most favorable
benefits provided by the Company to the estates and beneficiaries of peer
executives of the Company under such plans, programs, practices and policies
relating to death benefits, if any, as in effect with respect to other peer
executives and their beneficiaries at any time during the 120-day period
immediately preceding the Effective Date or, if more favorable to the
Executive's estate and/or the Executive's beneficiaries, as in effect on the
date of the Executive's death with respect to other peer executives of the
Company and their beneficiaries.

     (c)  DISABILITY. If the Executive's employment is terminated by reason of
the Executive's Disability during the Protected Period, this Agreement shall
terminate without further obligations to the Executive, other than for payment
of Accrued Obligations and the timely payment or provision of Other Benefits.
Accrued Obligations shall be paid to the Executive in a lump sum in cash within
30 days of the Date of Termination. With respect to the provision of Other
Benefits, the term Other Benefits as utilized in this Section 6(c) shall
include, and the Executive shall be entitled after the Disability Effective Date
to receive, disability and other benefits at least equal to the most favorable
of those generally provided by the Company to disabled executives and/or their
families in accordance with such plans, programs, practices and policies
relating to disability, if any, as in effect generally with respect to other
peer executives


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and their families at any time during the 120-day period immediately preceding
the Effective Date or, if more favorable to the Executive and/or the Executive's
family, as in effect at any time thereafter generally with respect to other peer
executives of the Company and their families.

     (d)  CAUSE; OTHER THAN FOR GOOD REASON. If the Executive's employment shall
be terminated for Cause during the Protected Period, this Agreement shall
terminate without further obligations to the Executive other than the obligation
to pay to the Executive (x) his Annual Base Salary through the Date of
Termination, (y) the amount of any compensation previously deferred by the
Executive, and (z) Other Benefits, in each case to the extent theretofore
unpaid. If the Executive voluntarily terminates employment during the Protected
Period, excluding a termination for Good Reason, this Agreement shall terminate
without further obligations to the Executive, other than for Accrued Obligations
and the timely payment or provision of Other Benefits. In such case, all Accrued
Obligations shall be paid to the Executive in a lump sum in cash within 30 days
of the Date of Termination.

     7.   NON-EXCLUSIVITY OF RIGHTS. Nothing in this Agreement shall prevent or
limit the Executive's continuing or future participation in any plan, program,
policy or practice provided by the Company or any of its affiliated companies
and for which the Executive may qualify, nor, subject to Section 12(f), shall
anything herein limit or otherwise affect such rights as the Executive may have
under any contract or agreement with the Company or any of its affiliated
companies. Amounts which are vested benefits or which the Executive is otherwise
entitled to receive under any plan, policy, practice or program of or any
contract or agreement with the Company or any of its affiliated companies at or
subsequent to the Date of Termination shall be payable in accordance with such
plan, policy, practice or program or contract or agreement except as explicitly
modified by this Agreement.

     8.   FULL SETTLEMENT. The Company's obligation to make the payments
provided for in this Agreement and otherwise to perform its obligations
hereunder shall not be affected by any set-off, counterclaim, recoupment,
defense or other claim, right or action which the Company may have against the
Executive or others. In no event shall the Executive be obligated to seek other
employment or take any other action by way of mitigation of the amounts payable
to the Executive under any of the provisions of this Agreement and such amounts
shall not be reduced whether or not the Executive obtains other employment. The
Company agrees to pay as incurred, to the full extent permitted by law, all
legal fees and expenses which the Executive may reasonably incur as a result of
any contest (regardless of the outcome thereof) by the Company, the Executive or
others of the validity or enforceability of, or liability under, any provision
of this Agreement or any guarantee of performance thereof (including as a result
of any contest by the Executive about the amount of any payment pursuant to this
Agreement), plus in each case interest on any delayed payment at the applicable
Federal rate provided for in Section 7872(f)(2)(A) of the Internal Revenue Code
of 1986, as amended (the "CODE").


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     9.   REDUCTION IN CERTAIN PAYMENTS.

     (a)  For purposes of this Section 9: (i) a "Payment" shall mean any payment
or distribution in the nature of compensation to or for the benefit of the
Executive, whether paid or payable pursuant to this Agreement or otherwise; (ii)
"Agreement Payment" shall mean a Payment paid or payable pursuant to this
Agreement (disregarding this Section); (iii) "Present Value" shall mean such
value determined in accordance with Sections 280G(b)(2)(A)(ii) and 280G(d)(4) of
the Internal Revenue Code of 1986, as amended (the "Code"); and (iv) "Reduced
Amount" shall mean an amount expressed in Present Value that maximizes the
aggregate Present Value of Agreement Payments without causing any Payment to be
nondeductible by the Company because of Section 280G of the Code.

     (b)  Anything in the Agreement to the contrary notwithstanding, in the
event PricewaterhouseCoopers (the "Accounting Firm") shall determine that
receipt of all Payments would subject the Executive to tax under Section 4999 of
the Code, the aggregate Agreement Payments shall be reduced (but not below zero)
to meet the definition of Reduced Amount. For purposes of reducing the Payments
to the Safe Harbor Amount, only amounts payable under this Agreement (and no
other Payments) shall be reduced.

     (c)  If the Accounting Firm determines that aggregate Agreement Payments
should be reduced to the Reduced Amount, the Company shall promptly give the
Executive notice to that effect and a copy of the detailed calculation thereof,
and the Executive may then elect, in his or her sole discretion, which and how
much of the Agreement Payments shall be eliminated or reduced (as long as after
such election the Present Value of the aggregate Agreement Payments equals the
Reduced Amount), and shall advise the Company in writing of his or her election
within ten days of his or her receipt of notice. If no such election is made by
the Executive within such ten-day period, the payments under Section 6(a)(i)(B)
shall be reduced first, and if any further reduction is necessary, the Company
may elect which other Agreement Payments shall be eliminated or reduced (as long
as after such election the Present Value of the aggregate Agreement Payments
equals the Reduced Amount) and shall notify the Executive promptly of such
election. All determinations made by the Accounting Firm under this Section
shall be binding upon the Company and the Executive and shall be made within 60
days of a termination of employment of the Executive. As promptly as practicable
following such determination, the Company shall pay to or distribute for the
benefit of the Executive such Agreement Payments as are then due to the
Executive under this Agreement and shall promptly pay to or distribute for the
benefit of the Executive in the future such Agreement Payments as become due to
the Executive under this Agreement.

     (d)  As a result of the uncertainty in the application of Section 4999 of
the Code at the time of the initial determination by the Accounting Firm
hereunder, it is possible that amounts will have been paid or distributed by the
Company to or for the benefit of the Executive pursuant to this Agreement which
should not have been so paid or distributed ("Overpayment") or that additional
amounts which will have not been paid or distributed by the Company to or for


                                      -11-
<PAGE>   12


the benefit of the Executive pursuant to this Agreement could have been so paid
or distributed ("Underpayment"), in each case, consistent with the calculation
of the Reduced Amount hereunder. In the event that the Accounting Firm, based
upon the assertion of a deficiency by the Internal Revenue Service against
either the Company or the Executive which the Accounting Firm believes has a
high probability of success determines that an Overpayment has been made, any
such Overpayment paid or distributed by the Company to or for the benefit of the
Executive shall be treated for all purposes as a loan to the Executive which the
Executive shall repay to the Company together with interest at the applicable
federal rate provided for in Section 7872(f)(2) of the Code; PROVIDED, however,
that no such loan shall be deemed to have been made and no amount shall be
payable by the Executive to the Company if and to the extent such deemed loan
and payment would not either reduce the amount on which the Executive is subject
to tax under Section 1 and Section 4999 of the Code or generate a refund of such
taxes. In the event that the Accounting Firm, based upon controlling precedent
or substantial authority, determines that an Underpayment has occurred, any such
Underpayment shall be promptly paid by the Company to or for the benefit of the
Executive together with interest at the applicable federal rate provided for in
Section 7872(f)(2) of the Code.

     (e)  All fees and expenses of the Accounting Firm in implementing the
provisions of this Section 9 shall be borne by the Company.

     10.  CONFIDENTIAL INFORMATION. The Executive shall hold in a fiduciary
capacity for the benefit of the Company all secret or confidential information,
knowledge or data relating to the Company or any of its affiliated companies,
and their respective businesses, which shall have been obtained by the Executive
during the Executive's employment by the Company or any of its affiliated
companies and which shall not be or become public knowledge (other than by acts
by the Executive or representatives of the Executive in violation of this
Agreement). After termination of the Executive's employment with the Company,
the Executive shall not, without the prior written consent of the Company or as
may otherwise be required by law or legal process, communicate or divulge any
such information, knowledge or data to anyone other than the Company and those
designated by it. In no event shall an asserted violation of the provisions of
this Section 10 constitute a basis for deferring or withholding any amounts
otherwise payable to the Executive under this Agreement.

     11.  SUCCESSORS. (a) This Agreement is personal to the Executive and
without the prior written consent of the Company shall not be assignable by the
Executive otherwise than by will or the laws of descent and distribution. This
Agreement shall inure to the benefit of and be enforceable by the Executive's
legal representatives.

     (b)  This Agreement shall inure to the benefit of and be binding upon the
Company and its successors and assigns.

     (c)  The Company will require any successor (whether direct or indirect, by
purchase, merger, consolidation or otherwise) to all or substantially all of the
business and/or


                                      -12-
<PAGE>   13


assets of the Company to assume expressly and agree to perform this Agreement in
the same manner and to the same extent that the Company would be required to
perform it if no such succession had taken place. As used in this Agreement,
"COMPANY" shall mean the Company as hereinbefore defined and any successor to
its business and/or assets as aforesaid which assumes and agrees to perform this
Agreement by operation of law, or otherwise.

     12.  MISCELLANEOUS. (a) This Agreement shall be governed by and construed
in accordance with the laws of the Commonwealth of Massachusetts, without
reference to principles of conflict of laws. The captions of this Agreement are
not part of the provisions hereof and shall have no force or effect. This
Agreement may not be amended or modified otherwise than by a written agreement
executed by the parties hereto or their respective successors and legal
representatives.

     (b)  All notices and other communications hereunder shall be in writing and
shall be given by hand delivery to the other party or by registered or certified
mail, return receipt requested, postage prepaid, addressed as follows:

     IF TO THE EXECUTIVE:





     IF TO THE COMPANY:

     United Asset Management Corporation
     One International Place
     Boston, Massachusetts  02110
     Attention:  General Counsel

or to such other address as either party shall have furnished to the other in
writing in accordance herewith. Notice and communications shall be effective
when actually received by the addressee.

     (c)  The invalidity or unenforceability of any provision of this Agreement
shall not affect the validity or enforceability of any other provision of this
Agreement.

     (d)  The Company may withhold from any amounts payable under this Agreement
such Federal, state, local or foreign taxes as shall be required to be withheld
pursuant to any applicable law or regulation.

     (e)  The Executive's or the Company's failure to insist upon strict
compliance with any provision of this Agreement or the failure to assert any
right the Executive or the Company may have hereunder, including, without
limitation, the right of the Executive to


                                      -13-
<PAGE>   14


terminate employment for Good Reason pursuant to Section 5(c)(i)-(v) of this
Agreement, shall not be deemed to be a waiver of such provision or right or any
other provision or right of this Agreement.

     (f)  The Executive and the Company acknowledge that, except as may
otherwise be provided under the Prior Agreement, or any other written agreement
between the Executive and the Company, the employment of the Executive by the
Company is "at will" and, subject to Section 1(a) hereof, prior to the Effective
Date, the Executive's employment may be terminated by either the Executive or
the Company at any time prior to the Effective Date, in which case the Executive
shall have no further rights under this Agreement. From and after the Effective
Date this Agreement shall supersede any other agreement between the parties with
respect to the subject matter hereof, except to the extent specifically provided
herein with respect to the Prior Agreement.


                                      -14-
<PAGE>   15


     IN WITNESS WHEREOF, the Executive has hereunto set the Executive's hand
and, pursuant to the authorization from its Board of Directors, the Company has
caused these presents to be executed in its name on its behalf, all as of the
day and year first above written.


                                             /s/ James F. Orr III
                                             ---------------------------------
                                             James F. Orr III



                                             UNITED ASSET MANAGEMENT
                                              CORPORATION



                                             By: /s/ John A. Shane
                                                 -------------------------------
                                                 John A. Shane, duly authorized


                                      -15-