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                                                                  EXHIBIT 10(FF)
                                                                                

                    EMPLOYMENT AND NONCOMPETITION AGREEMENT
                    ---------------------------------------

     This agreement is made effective January 1, 1999 (the "Commencement Date"),
between American Dental Partners, Inc., a Delaware corporation (the "Company"),
and Joseph V. Errante, D.D.S. (the "Employee").

                            Background Information
                            ----------------------

     The Employee has been employed by Innovative Practice Concepts, Inc., an
Arizona corporation and wholly-owned subsidiary of the Company ("IPC"), pursuant
to an Employment and Noncompetition Agreement dated January 1, 1998 between the
Employee and IPC (the "Original Agreement").  Concurrently with the execution of
this agreement, the Employee and IPC are executing a termination of the Original
Agreement, effective as of 11:59 p.m., December 31, 1998, and the Employee and
the Company desire to provide for the employment of the Employee by the Company
on the terms and conditions set forth below.

                            Statement of Agreement
                            ----------------------

     The Company and the Employee (the "Parties") hereby acknowledge the
accuracy of the foregoing Background Information and agree as follows:

     (S)1.  Employment.  Upon the terms and subject to the conditions described
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in this agreement, the Company hereby employs the Employee and the Employee
hereby accepts employment by the Company.

     (S)2.  Term.  Employee's employment with the Company pursuant to this
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agreement shall be for the period beginning on the Commencement Date and ending
on the fourth anniversary of the Commencement Date (the "Initial Term"), unless
or until sooner terminated pursuant to (S)7 of this agreement.  This agreement
may be extended or renewed after the expiration of the Initial Term, but only by
mutual written agreement of the Parties.  When permitted by the context, any
reference in this agreement to the "term of this agreement" shall include the
Initial Term and the period of any such extensions or renewals.

     (S)3.  Services.  The Employee shall serve as Vice President, Regional
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Operations of the Company, shall report directly to the Chief Executive Officer
of the Company (the "CEO"), and shall devote his full business and professional
time, attention, energy, loyalty, and skill to the Company's business,
performing such executive or administrative tasks and having such
responsibilities as may be assigned to him from time to time by the CEO or the
Board of Directors of the Company (the "Board").

     (S)4.  Compensation. As compensation for his services under this agreement,
            ------------  
the Company shall pay the Employee a base salary at the annual rate of $140,000
(the "Base Salary"), payable in bi-weekly installments, in arrears, and in
accordance with the Company's 
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general policies and procedures for payment of salaries to its executive
personnel. The Employee's performance shall be reviewed not less often than
annually for the purpose, among others, of considering potential increases in
the Base Salary, but the Company shall not be obligated to make any such
increases.

     In addition, the Employee may earn an annual bonus for each calendar year
during the term of this agreement in an amount up to 35% of the Base Salary (as
in effect from time to time), which bonus shall be based upon and tied to the
achievement of various objectives to be prepared annually by the CEO.

     (S)5.  Fringe Benefits and Perquisites.  During the term of this agreement,
            -------------------------------                                     
the Employee shall also be entitled to the following fringe benefits and
perquisites:

            (a)  Group health and welfare benefits comparable to those offered
     generally to the Company's executive personnel from time to time;

            (b)  Four weeks paid vacation during each year of this agreement;

            (c)  Participation in such stock option plans of the Company as may
     be designated from time to time by the Board (or a duly authorized
     committee of such Board), in its discretion, subject to all terms and
     conditions of such plans; and

            (d)  Such other benefits and perquisites as may be offered generally
     to the Company's executive personnel from time to time pursuant to such
     terms, conditions, and policies as may be approved by the Board.

     (S)6.  Confidentiality; Noncompetition. The Employee shall not, directly or
            -------------------------------      
indirectly, at any time (whether during the term of this agreement or
thereafter), disclose any Confidential Information (defined below) to any
person, association, or other entity (other than the Affiliated Companies, as
defined below), or use, or permit or assist any person, association, or other
entity (other than the Affiliated Companies) to use, any Confidential
Information, excepting only: (i) Confidential Information which (A) is then
generally available to or obtainable by the public and which did not become so
available or obtainable through the breach of any provision of this agreement by
the Employee, or (B) is obtained by the Employee on a non-confidential basis
from a source other than an Affiliated Company or any agent or other
representative of an Affiliated Company and such source had the right to
disclose such Confidential Information to the Employee without violating any
legal, contractual, fiduciary, or other obligation; and (ii) disclosures
required by applicable law.

     Upon termination of his employment by the Company (for any reason), the
Employee shall immediately deliver to the Company all documents and other
materials containing any Confidential Information which are in his possession or
under his control.

     During the Restricted Period (defined below), the Employee shall not,
directly or indirectly (whether individually or as a shareholder or other owner,
partner, member, director, officer, employee, consultant, creditor or agent of
any person, association, or other entity):

                                      -2-
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          (a)  Enter into, engage in, or promote or assist (financially or
     otherwise), directly or indirectly, any business which (i) provides dental
     services anywhere in the Restricted Territory, or (ii) competes with the
     business of any Affiliated Company (the "Business") anywhere in the
     Restricted Territory, provided that the foregoing shall not preclude the
     Employee from owning less than 1% of the outstanding capital stock of any
     corporation whose shares are publicly traded on a national securities
     exchange or system;

          (b)  Solicit or attempt to solicit business in competition with the
     Business from any insurance company, any dental plan provider, any person
     or entity which provides professional dental care services to the public,
     or any other third party to which any Affiliated Company provides
     management, consulting, or other services (in any such case, a "Restricted
     Company"), or interfere or attempt to interfere with any relationship of
     any Affiliated Company with any Restricted Company;

          (c)  Induce or encourage any employee, officer, director, agent,
     supplier, or independent contractor of any Affiliated Company to terminate
     its relationship with any such Affiliated Company, or otherwise interfere
     or attempt to interfere in any way with any Affiliated Company's
     relationships with its employees, officers, directors, agents, suppliers,
     independent contractors, or others;

          (d)  Employ or engage any person who, at any time within the one-year
     period immediately preceding such employment or engagement, was an
     employee, officer, director, or agent of any Affiliated Company; or

          (e)  Make any statement (oral or written) or take any other action
     which would tend to disparage or diminish the reputation of any Affiliated
     Company.

     For purposes of this agreement:

          (i)   "Affiliated Companies" shall include the Company and all
     subsidiaries or affiliates of the Company other than Summit Ventures IV,
     L.P. and any of its affiliates which are not engaged in a business similar
     to that of the Company or any of its subsidiaries;

          (ii)  "Confidential Information" shall mean all trade secrets,
     proprietary data, and other confidential information of any Affiliated
     Company, including without limitation financial information, information
     relating to business operations, services, promotional practices, and
     relationships with Restricted Companies, suppliers, employees, independent
     contractors, or other parties, and any information which any Affiliated
     Company is obligated to treat as confidential pursuant to any course of
     dealing or any agreement to which it is a party or otherwise bound;

                                      -3-
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          (iii) the "Restricted Period" shall mean the period beginning on the
     Commencement Date and ending on the later of (A) the fourth anniversary of
     the Commencement Date or (B) the second anniversary of the date (the
     "Termination Date") of termination (for any reason) of Employee's
     employment with the Company (whether pursuant to this agreement or
     otherwise); and

          (iv)  "Restricted Territory" shall mean (A) at any time prior to the
     Termination Date, all metropolitan statistical areas ("MSAs") and all
     cities, towns, villages, townships, and other similar political
     subdivisions, whether incorporated or unincorporated (collectively,
     "Cities"), in which any Affiliated Company then owns, leases, manages, or
     operates an office or other facility, and (B) on or after the Termination
     Date, all MSAs and Cities in which any Affiliated Company owns, leases,
     manages, or operates an office or other facility on the Termination Date.
     Notwithstanding the foregoing, with respect to (S)6(a)(i), above, and, if,
     but only if, either or both of the Employee and Margaret R. Errante,
     D.D.S., along with such dental hygienists, dental assistants, and other 
     non-dentist personnel as either of them deems necessary (subject to
     (S)(S)6(c) and (d), above), personally provide clinical care to all
     patients who result from the activities described in (S)6(b), above, then
     also with respect to (S)6(b), "Restricted Territory" shall mean (1) at any
     time prior to the Termination Date, the geographic area within a radius of
     seven miles from any offices or facilities operated or otherwise utilized
     by Associated Dental Care Providers, P.C., an Arizona professional
     corporation ("ADCP"), at which any dentist employed or otherwise retained
     by ADCP is then scheduled to see patients, and (2) on or after the
     Termination Date, the geographic area within a radius of seven miles of any
     offices or facilities operated or otherwise utilized by ADCP at which any
     dentist employed or otherwise retained by ADCP has been scheduled to see
     patients on a regular basis or has seen patients on a regular basis at any
     time during the two-year period immediately preceding the Termination Date.

     The Employee acknowledges that (1) the provisions of this section are
fundamental and essential for the protection of the Company's legitimate
business and proprietary interests, (2) such provisions are reasonable and
appropriate in all respects, and (3) in the event of any violation by the
Employee of any of such provisions, the Company would suffer irreparable harm
and its remedies at law would be inadequate.  In the event of any violation or
attempted violation of such provisions by the Employee, the Company shall be
entitled to a temporary restraining order, temporary and permanent injunctions,
specific performance, and other equitable relief, without any showing of
irreparable harm or damage or the posting of any bond, in addition to any other
rights or remedies which may then be available to the Company.

     (S)7.  Termination.  The Employee's employment with the Company shall
            -----------                                                   
terminate automatically upon the death of the Employee and may be terminated by
the Company, without any further obligation on the part of the Company (except
as provided in clause (c), below), immediately upon notice to the Employee under
any of the following circumstances:

            (a)  At any time for Cause (defined below);

                                      -4-
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          (b)  At any time when the Employee is under a Long-Term Disability
     (defined below); or

          (c)  At any time without Cause; provided that if the Company
     terminates the Employee's employment pursuant to this clause (c) and no
     other basis for termination exists under this agreement, then the Employee
     shall be entitled to severance payments in an aggregate amount equal to the
     Base Salary for a period equal to the lesser of one year or the period
     remaining in the Initial Term at the time of such termination. Any such
     severance payments shall be payable periodically in the same manner as the
     Base Salary is payable under (S)4 of this agreement, and, notwithstanding
     any other provisions of this agreement to the contrary, such severance
     payments shall be payable only so long as the Employee is in full
     compliance with the provisions of (S)6 of this agreement.

     For purposes of this agreement:

     (i)  "Cause" shall mean:

          (A)  any act constituting (1) a felony under the federal laws of the
     United States, the laws of any state, or any other applicable law, (2)
     fraud, embezzlement, misappropriation of assets, willful misfeasance, or
     dishonesty, or (3) other criminal conduct which in any way materially and
     adversely affects the reputation, goodwill, or business position of the
     Company;

          (B)  the failure of the Employee to perform and observe all material
     obligations and conditions to be performed and observed by the Employee
     under this agreement, or to perform his duties in accordance with the
     policies, programs, budgets, procedures, and directions established from
     time to time by the CEO or the Board (any such failure, a "Performance
     Failure"), and to correct such Performance Failure promptly following
     notice from the Company to do so; or

          (C)  having corrected (or the Company having waived the correction of)
     a Performance Failure, the occurrence of any subsequent Performance
     Failure; and

     (ii) "Long-Term Disability" shall mean that, because of physical or mental
     incapacity, it is more likely than not that the Employee will be unable,
     within 180 days after such incapacity commenced, to perform the essential
     functions of his position with the Company, with or without reasonable
     accommodation. In the event of any disagreement about whether or when the
     Employee is under a Long-Term Disability, the question shall be determined:
     (A) by a physician selected by agreement between the Employee and the
     Company if such a physician is selected within 10 days after either of them
     requests the other so to agree; or, if not, (B) by two physicians, the
     first of whom shall be selected by the Employee and the second of whom
     shall be selected by the Company or, if the Employee fails to make a
     selection within 10 days after being requested to do so by the Company, the
     second physician shall be selected by the first physician; or, if the two
     physicians fail to agree, (C) by a third physician selected by the first
     two physicians. The Employee shall submit to all reasonable examinations
     requested by any such physicians.

                                      -5-
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     (S)8.  Capacity.  The Employee represents and warrants to the Company that
            --------   
he has the capacity and right to enter into this agreement and perform all of
his obligations under this agreement without any restriction.

     (S)9.  Remedies.  All rights and remedies of either Party under this 
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agreement are cumulative and in addition to all other rights and remedies which
may be available to that Party from time to time, whether under any other
agreement, at law, or in equity.

     (S)10. Survival.  The termination of the Employee's employment with the
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Company (for any reason) shall not relieve either Party of any of that Party's
obligations under this agreement existing at, arising as a result of, or
relating to acts or omissions occurring prior to, such termination.  Without
limiting the generality of the preceding sentence, in no event shall the
termination of such employment modify or affect any obligations of the Employee
or rights of the Company under (S)6 of this agreement, all of which shall
survive the termination of such employment.

     (S)11. Notices.  All notices and other communications under this agreement
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to any Party shall be in writing and shall be deemed given when delivered
personally, telecopied (which is confirmed) to that Party at the telecopy number
for that Party set forth below, mailed by certified mail (return receipt
requested) to that Party at the address for that Party (or at such other address
for such Party as such Party shall have specified in notice to the other Party)
or delivered to Federal Express, UPS, or any similar express delivery service
for delivery to that Party at that address:

          (a)  If to the Company:

               American Dental Partners, Inc.
               301 Edgewater Place
               Suite 320
               Wakefield, Massachusetts  01880-1249
               Attention: Gregory A. Serrao, Chief Executive Officer
               Telecopy No.: (617) 224-4216

               with a copy to

               Baker & Hostetler
               65 East State Street
               Columbus, Ohio  43215
               Attention: Gary A. Wadman, Esq.
               Telecopy No.: (614) 462-2616

                                      -6-
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          (b)  If to the Employee:

                   Joseph V. Errante, D.D.S.
                   2100 North Kolb Road, Suite 105
                   Tucson, Arizona  85715
                   Telecopy No.: (520) 290-9317

                   with a copy to:

                   DeConcini McDonald Yetwin & Lacy, P.C.
                   2525 East Broadway Boulevard
                   Suite 200
                   Tucson, Arizona  85716-5300
                   Attention:  James A. Jutry, Esq.
                   Telecopy No.:  (520) 322-5585

     (S)12. Severability.  The intention of the Parties is to comply fully with
            ------------                                                       
all rules, laws, and public policies to the extent possible.  If and to the
extent that any court of competent jurisdiction is unable so to construe any
provision of this agreement and holds that provision to be invalid, such
invalidity shall not affect the remaining provisions of this agreement, which
shall remain in full force and effect.  With respect to any provision in this
agreement finally determined by such a court to be invalid or unenforceable,
such court shall have jurisdiction to reform this agreement to the extent
necessary to make such provision valid and enforceable, and, as reformed, such
provision shall be binding on the Parties.

     (S)13. Non-Waiver.  No failure by either Party to insist upon strict
            ----------                                                   
compliance with any term of this agreement, to exercise any option, to enforce
any right, or to seek any remedy upon any default of the other Party shall
affect, or constitute a waiver of, the other Party's right to insist upon such
strict compliance, exercise that option, enforce that right, or seek that remedy
with respect to that default or any prior, contemporaneous, or subsequent
default.  No custom or practice of the Parties at variance with any provision of
this agreement shall affect, or constitute a waiver of, either Party's right to
demand strict compliance with all provisions of this agreement.

     (S)14. Complete Agreement.  This agreement and all documents referred to in
            ------------------                                                  
this agreement, all of which are hereby incorporated herein by reference,
contain the entire agreement between the Parties and supersede all other
agreements and understandings between the Parties with respect to the subject
matter of this agreement.  No alterations, additions, or other changes to this
agreement shall be made or be binding unless made in writing and signed by both
Parties.

     (S)15. Governing Law.  This agreement shall be governed by and construed in
            -------------                                                       
accordance with the laws of the State of Arizona without regard to principles of
conflicts of law.

                                      -7-
<PAGE>
 
     (S)16. Captions.  The captions of the various sections of this agreement 
            --------       
are not part of the context of this agreement, are only guides to assist in
locating those sections, and shall be ignored in construing this agreement.

     (S)17. Genders and Numbers.  Where permitted by the context, each pronoun
            -------------------                                               
used in this agreement includes the same pronoun in other genders and numbers,
and each noun used in this agreement includes the same noun in other numbers.

     (S)18. Successors.  This agreement shall be personal to the Employee and no
            ----------                                                          
rights or obligations of the Employee under this agreement may be assigned by
the Employee to any third party.  Any assignment or attempted assignment by the
Employee in violation of the preceding sentence shall be null and void.  Subject
to the foregoing, this agreement shall be binding upon, inure to the benefit of,
and be enforceable by and against the successors and assigns of each Party.


AMERICAN DENTAL PARTNERS, INC.



By  /s/ Gregory A. Serrao                    /s/ Joseph V.Errante, D.D.S.
   ----------------------------              ----------------------------
   Gregory A. Serrao, President              JOSEPH V. ERRANTE, D.D.S.

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