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                                                                   EXHIBIT 10.15

                        ADMINISTRATIVE SERVICES AGREEMENT
                                    "Yonkers"

      This Administrative Services Agreement ("Agreement") is entered into as of
January 1, 1999 ("Effective Date") by and among NEW YORK RADIATION THERAPY
MANAGEMENT SERVICES, INCORPORATED, a New York corporation ("MANAGEMENT
SERVICES") and YONKERS RADIATION MEDICAL PRACTICE, P.C., a New York professional
corporation (the "PC").

                                    RECITALS

      A.    The PC is a New York professional corporation that engages in the
business of providing or arranging for the provision of health care services
(the "Practice"). The PC has entered into and throughout the term of this
Agreement may (if MANAGEMENT SERVICES does not do so itself as provided herein)
continue to enter into arrangements with insurers, HMOs and other third-party
payors ("Payers") to provide or arrange for the provision of health care
services to persons covered by those Payors ("Enrollees").

      B.    The PC has entered into written employment agreements with
physicians and other health care providers and health care professionals
("Employed Providers") licensed to practice in the State of New York. The PC may
also enter into independent contractor agreements with various physicians and
other health care providers and health care professionals ("Contracting
Providers") to assist the PC in providing or arranging for the provision of
health care services to Enrollees and other patients of the PC (collectively,
"Patients").

      C.    MANAGEMENT SERVICES engages in the business of providing certain
administrative and support services concerning the day-to-day affairs of
radiation therapy offices (the "Offices"), both in their startup and established
phases, and in providing space in the Offices, equipment, furnishings, supplies,
inventory, personnel and working capital to Offices and facilities management in
connection therewith.

      D.    The PC desires to secure certain administrative services from
MANAGEMENT SERVICES in connection with its operation of the Practice in the
Offices, and to lease from MANAGEMENT SERVICES certain space, equipment,
furnishings, supplies and inventory in connection therewith.

      E.    The PC and MANAGEMENT SERVICES desire to enter into a written
agreement for the provision by MANAGEMENT SERVICES, on an exclusive basis, of
administrative services to the PC with respect to the Practice, and for the
provision of space, furnishings, supplies, inventory, non-medical personnel and
management services to the Practice, so as to permit the PC to devote its
efforts on a concentrated and continuous basis to the rendering of medical
services to its Patients.

      NOW, THEREFORE, in consideration of the mutual covenants and conditions
contained herein, the parties agree as follows:

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                          I. RESPONSIBILITIES OF THE PC

      1.1.  Sole Responsibility for All Medical and Professional Matters. All
medical and professional matters relating to the provision of radiation therapy
or oncology services at the Offices shall be the sole responsibility of the PC.
The PC shall use and occupy the facilities provided by MANAGEMENT SERVICES
hereunder exclusively for the practice of medicine. The PC expressly
acknowledges that the medical practice or practices conducted at these
facilities shall be conducted solely by Employed Providers and Contracting
Providers.

      1.2.  Employed Providers and Contracting Providers. The PC shall have
complete control of and responsibility for the hiring, engagement, compensation,
supervision evaluation, and termination of all Employed Providers and
Contracting Providers, including nurses, physician assistants and other licensed
healthcare professionals. With respect to physicians, the PC shall only employ
and contract with licensed physicians meeting applicable credentialing
guidelines established by the PC. The PC shall be responsible for the payment of
salaries and wages, compensation, payroll taxes, employee benefits, and all
other taxes and charges now or hereafter applicable to Employed Providers and
Contracting Providers. Prior to making any changes with respect to any of the
Employed Providers or Contracting Providers, the PC shall consult with
MANAGEMENT SERVICES, although MANAGEMENT SERVICES shall provide input only and
shall not conclude whether an Employed Provider should be hired or terminated.
The PC shall also consult with MANAGEMENT SERVICES with regard to the terms of
contracts entered into between the PC and Employed Providers and Contracting
Providers and the terms and conditions of their employment or engagement as
independent contractors, as applicable.

      1.3.  Fees, Charges and Payor Agreements. The PC shall, after consultation
with MANAGEMENT SERVICES, determine the fees, charges, premiums, or other
amounts due in connection with its delivery of health care services to Patients.
Such fees, charges, premiums, or other amounts, regardless of whether determined
on a fee-for-service, capitated, prepaid, or other basis, shall be reasonable
and consistent with the fees, charges, premiums and other amounts due to health
care providers for similar services within the community under the type of
reimbursement program involved. MANAGEMENT SERVICES shall provide input relating
to the foregoing but shall not conclude the level of fees, charges, premiums, or
other amounts the PC should establish.

      1.4.  Compliance with Law. The PC shall require all of its Employed
Providers and Contracting Providers to comply with all laws, regulations, and
ethical and professional standards applicable to the practice of medicine.
Employed Providers and Contracting Providers who are physicians shall at all
times be licensed to practice medicine in the State of New York and all other
states in which an Office at which such physician provides patients medical
services is located.

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      1.5.  Offices; Hours of Operation: Staffing. The PC shall conduct the
Practice from the current Office located in Yonkers, New York at 136 South
Broadway, Yonkers, New York 10701, as well as such hospitals and other
facilities as may be agreed upon by MANAGEMENT SERVICES and the PC from time to
time. Any additional or substitute Office shall be deemed to be part of the
Practice for the purposes of this Agreement. The hours of operation and the
medical staffing of the Offices shall be established by the agreement of the PC
and MANAGEMENT SERVICES from time to time hereafter.

      1.6.  Quality Assurance. The PC shall rigorously monitor utilization and
quality of services provided by Employed Providers and Contracting Providers,
shall develop, maintain and administer quality assurance programs and
performance standards and shall take all steps necessary to remedy any and all
deficiencies in the efficiency or the quality of medical care provided.

      1.7.  Patient Referrals. The parties agree that the benefits to the PC
hereunder do not require, are not payment for, and are not in any way contingent
upon the admission, referral or any other arrangements for the provision of any
item or service offered by MANAGEMENT SERVICES or any Affiliate, as defined in
Section 8.21 of this Agreement, of MANAGEMENT SERVICES to any of the PC's
Patients in any facility or laboratory controlled, managed or operated by
MANAGEMENT SERVICES or any Affiliate of MANAGEMENT SERVICES.

      1.8.  Professional Dues and Education Expenses. The PC and its Employed
Providers and Contracting Providers shall be solely responsible for the cost of
membership in professional associations, and continuing professional education.
The PC shall ensure that each of its Employed Providers and Contracting
Providers participates in such continuing medical education as is necessary for
such provider to remain current with professional licensure and community
standards.

      1.9.  Professional Insurance Eligibility. The PC shall cooperate with
MANAGEMENT SERVICES in the obtaining and retaining of professional liability
insurance by assuring that either its Employed Providers and Contracting
Providers are insurable or instituting proceedings to terminate any Employed
Provider of Contracting Provider who is not insurable or loses his or her
insurance eligibility. Termination shall be effective no more than thirty (30)
days from such determination. The PC shall require all Employed Providers and
Contracting Providers to participate in an on-going risk management program.

      1.10. Fees for Professional Services. MANAGEMENT SERVICES shall be solely
responsible for legal, accounting and other professional services incurred by
the PC in operating the Practice absent a violation by the PC of any provisions
of this Agreement.

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                   II. RESPONSIBILITIES OF MANAGEMENT SERVICES

      2.1.  General Responsibility. MANAGEMENT SERVICES shall have general
responsibility for providing fiscal services, administrative services, and other
strategic and tactical support services to the PC with respect to the Practice,
except as otherwise provided in this Agreement. MANAGEMENT SERVICES shall
perform all required functions in accordance with sound management techniques.
Notwithstanding MANAGEMENT SERVICES' general and specific rights and
responsibilities set forth in this Agreement, the PC shall have full authority
and control with respect to all medical, professional and ethical determinations
over the PC's Practice to the extent required by federal, state and local laws,
rules and regulations. MANAGEMENT SERVICES shall not engage in activities which
constitute the practice of medicine under applicable laws. MANAGEMENT SERVICES
shall neither exercise control over nor interfere with the physician-patient
relationship, which shall be maintained strictly between the physicians employed
by or contracting with the PC and the PC's Patients.

      2.2.  Responsibilities with Regard to Selected Patient- Related Matters.

            (a)   Patient Relations, Scheduling, Etc. MANAGEMENT SERVICES shall
assist the PC in maintaining positive Patient relations by, among other things,
in conjunction with and at the direction of the PC: scheduling Patient
appointments; responding to Patient grievances and complaints in matters other
than medical evaluation, diagnosis, and treatment; and establishing and
maintaining in the PC's name and on its behalf Patient transfer arrangements to
expedite referrals where medically necessary, as determined and requested by the
attending physician.

            (b)   Recordkeeping. MANAGEMENT SERVICES shall assist the PC in
maintaining Patient medical records in accordance with applicable laws
concerning their confidentiality and retention, and promptly making such records
available to the PC's Employed Providers, Contracting Providers and other
appropriate recipients. Notwithstanding the foregoing sentence, Patient medical
records shall be and shall remain the property of the PC, and the content
thereof shall be solely the responsibility of the PC.

            (c)   Quality Assurance.

                  (i)   In General. MANAGEMENT SERVICES shall assist the PC, in
accordance with criteria established by the PC, in the development and
implementation of appropriate quality assurance programs, including development
of performance and utilization standards, sampling techniques for case review,
and preparation of appropriately documented studies. Notwithstanding the
foregoing, MANAGEMENT SERVICES shall not perform any duties that constitute the
corporate practice of medicine in New York and all other states in which an
Office at which the PC provides patient medical services is located.

                  (ii)  Periodic Independent Review. On behalf of the PC,
MANAGEMENT SERVICES may periodically perform quality assurance and utilization
reviews through nurses employed by it; provided, however, that MANAGEMENT

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SERVICES shall not engage in activities which constitute the practice of
medicine under applicable law. Alternatively, MANAGEMENT SERVICES may
periodically arrange for an independent quality assurance and utilization review
to be performed by persons who are unrelated to the PC or MANAGEMENT SERVICES,
or to any Affiliate of the PC or MANAGEMENT SERVICES, which has expertise in
such areas, and which has been approved in advance by the PC. Such review shall
include a random sampling of medical records (consistent with laws regarding the
confidentiality of medical records), an analysis of the PC's quality assurance
utilization review procedures, and an analysis of the appropriateness of costs
associated with operating the PC's medical practice at the Practice.

      2.3.  Responsibilities with Regard to Selected Financial Matters.

            (a)   Billing. MANAGEMENT SERVICES shall submit on a timely basis
all bills and necessary documentation required by Patients and Payors in order
to obtain payment in connection with the PC's delivery of health care services
at the Practice or its arrangement for the delivery of such services. In seeking
such payment, MANAGEMENT SERVICES shall act as the PC's exclusive agent in
billing and collecting professional fees, charges and other amounts owed to the
PC. In this connection, the PC hereby appoints MANAGEMENT SERVICES, during the
term of this Agreement, as the PC's true and lawful attorney-in-fact, with power
of substitution, for the following purposes relating to the Practice:

                  (i)   To bill the PC's Patients on the PC's behalf.

                  (ii)  To collect accounts receivable generated by such
billings on the PC's behalf, including, where deemed appropriate by MANAGEMENT
SERVICES and approved in advance by the PC, settling and compromising claims,
assigning such accounts receivable to a collection agency or the bringing of
legal action against a Patient or Payor on the PC's behalf.

                  (iii) To receive payments on behalf of the PC from Patients
and Payors, to cause such payments to be deposited into appropriate depository
accounts (each such depository account, a "Collections Account") and to write
checks against or otherwise withdraw such payments to pay the PC Expenses (as
hereinafter defined).

            (b)   Accounting. MANAGEMENT SERVICES shall direct and maintain the
operation of an appropriate accounting system with respect to the PC's operation
of the Practice which shall perform all bookkeeping and accounting services
required for the operation of the Practice, including the maintenance, custody
and supervision of business records, ledgers and reports; the establishment,
administration and implementation of accounting procedures, controls and
systems. Such accounting system shall allow MANAGEMENT SERVICES to prepare the
reports specified in Section 2.3(c).

            (c)   Reporting. MANAGEMENT SERVICES shall present to the PC reports
on the financial condition of the PC on the basis set forth below in clauses (i)
and (ii) and such other reports that the PC may reasonably request, including
daily

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activity reports, weekly analyses, alternative delivery system reports, backlog
reports and the like. MANAGEMENT SERVICES also shall provide such reports as may
be required by any regulatory agency having jurisdiction over the operations of
the PC.

            The reports initially required to be delivered to the PC under this
Section 2.3(c) with respect to the Practice are as follows:

                  (i)   As soon as possible after the close of each month, a
balance sheet and a related statement of revenues and expenses showing the
results of the PC's operations for the preceding month of the fiscal year and
the year to date.

                  (ii)  As soon as possible after the close of each fiscal year,
a balance sheet and related statement of revenues and expenses showing the
results of the PC's operations during that fiscal year.

      2.4.  Responsibilities with Respect to Facilities Management.

            (a)   Office Management Services. MANAGEMENT SERVICES shall provide,
supervise and direct the development of appropriate and efficient office
management services with respect to the PC's operation of the Practice.

            (b)   Offices. MANAGEMENT SERVICES shall provide, manage and
maintain the real property comprising the Offices and reasonable improvements
during the term of this Agreement. In consultation with the PC, MANAGEMENT
SERVICES shall oversee all management, maintenance and other decisions
pertaining to the Offices consistent with the terms of this Agreement.
MANAGEMENT SERVICES shall maintain the Offices in good condition and repair,
reasonable wear and tear excepted. MANAGEMENT SERVICES shall provide such
additional and/or replacement facilities as the PC and MANAGEMENT SERVICES
agree, from time to time. MANAGEMENT SERVICES shall provide the PC with all
utilities (including water, gas and electricity), heat, air conditioning,
telephone, janitorial services and disposal services (including the disposal of
medical wastes) required in connection with the operation of the Offices.

            (c)   Use of Assets.

                  (i)   MANAGEMENT SERVICES shall lease or purchase and, when
necessary, replace equipment and furnishings needed for the delivery of health
care services by the PC at the Offices and for the delivery of services provided
by MANAGEMENT SERVICES pursuant to this Agreement. MANAGEMENT SERVICES shall
consult with the PC with respect to the suppliers, prices and specifications of
such equipment and furnishings. MANAGEMENT SERVICES shall use its best efforts
to keep and maintain the equipment and furnishings used by the PC at the Offices
in good working order and condition.

                  (ii)  All assets provided or purchased under this Agreement by
MANAGEMENT SERVICES, including any management information systems, shall

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remain the property of MANAGEMENT SERVICES and the PC shall have the right to
use such assets only during the term of this Agreement.

                  (iii) Nothing in this Agreement shall be construed to affect
or limit in any way the professional discretion of the PC to select and use
equipment, furnishings, inventory and supplies purchased by MANAGEMENT SERVICES
in accordance with the terms of this Agreement insofar as such selection or use
constitutes or might constitute the practice of medicine.

            (d)   Supplies and Inventory. MANAGEMENT SERVICES shall provide and
replenish, as necessary and as may be permitted by applicable law, the inventory
and supplies needed for the delivery of medical services by the PC, and for the
delivery of services by MANAGEMENT SERVICES pursuant to this Agreement.
MANAGEMENT SERVICES shall consult with the PC with respect to the suppliers,
prices and specifications of such inventory and supplies.

            (e)   No Warranties. THE PC ACKNOWLEDGES THAT MANAGEMENT SERVICES
MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED, AS TO THE
SUITABILITY OR ADEQUACY OF ANY FACILITIES, EQUIPMENT, FURNISHINGS, INVENTORY OR
SUPPLIES PROVIDED PURSUANT TO THIS AGREEMENT FOR THE CONDUCT OF A MEDICAL
PRACTICE OR FOR ANY OTHER PARTICULAR PURPOSE.

      2.5.  Other Responsibilities.

            (a)   Public Relations. MANAGEMENT SERVICES shall provide services
reasonably necessary for enhancing public relations for the PC's health care
services and shall submit any public relations programs for prior review and
revision, if necessary, and approval by the PC. Such public relations shall
comply with applicable laws and regulations governing the use of promotional
activities by the medical profession and with applicable standards of medical
ethics.

            (b)   Insurance.

                  (i)   Property and Liability Insurance. MANAGEMENT SERVICES
shall obtain and maintain during the term of this Agreement, if available on
commercially reasonable terms, (a) property damage insurance protecting the
Practice premises and the personal property located therein against such hazards
and in such amounts as MANAGEMENT SERVICES determines are reasonably prudent;
and (b) general liability insurance in such amounts as MANAGEMENT SERVICES
determines are reasonably prudent.

                  (ii)  General Liability Insurance. The PC shall obtain and
maintain during the term of this Agreement general liability insurance in such
amounts as the PC determines are reasonably prudent. The PC shall name
MANAGEMENT SERVICES as an additional insured on such policies.

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                  (iii) Malpractice Insurance. It is understood that the PC and
its Employed Providers shall, at the PC's cost, at all times be covered by
malpractice insurance with coverage in usual and customary amounts for
practitioners of the same profession and specialties in New York and, if
applicable, other states. The PC shall ensure that its written agreements with
Contracting Providers who are physicians require such Contracting Providers to
at all times be covered by malpractice insurance in amounts that are usual and
customary for practitioners of the same profession and specialty in New York
and, if applicable, other states. Such malpractice policies shall name
MANAGEMENT SERVICES as an additional insured.

                  (iv)  Copies of Insurance Policies. MANAGEMENT SERVICES or the
PC shall, upon request by the PC or MANAGEMENT SERVICES, as the case may be,
promptly provide the PC or MANAGEMENT SERVICES, as the case may be, with copies
of all policies of insurance that it procures under this Agreement. Each such
policy shall provide that it cannot be modified or terminated except after
thirty (30) days written notice to MANAGEMENT SERVICES.

            (c)   Personnel. MANAGEMENT SERVICES shall furnish the services of
all personnel other than physicians, nurses, physician assistants or other
licensed healthcare professionals required for the operation of the Practice.
Except as specifically provided in this Section 2.5(c). MANAGEMENT SERVICES has
the power to recruit, hire, train, promote, assign, set the compensation level
for, and discharge all personnel other than physicians, nurses, physician
assistants or other licensed healthcare professionals. Any personnel employed by
MANAGEMENT SERVICES who perform patient care services shall perform such
services under the exclusive direction, supervision and control of the PC, while
all other services of MANAGEMENT SERVICES personnel shall be performed under the
exclusive direction, supervision and control of MANAGEMENT SERVICES. If the PC
is dissatisfied with the services of any personnel employed by MANAGEMENT
SERVICES, the PC shall consult with MANAGEMENT SERVICES. MANAGEMENT SERVICES
shall in good faith determine whether the performance of that employee could be
brought to acceptable levels through counsel and assistance, or whether, if
requested by the PC (provided that such employee is not an officer or senior
manager of MANAGEMENT SERVICES), such employee should be removed from providing
services for the PC. Employee assignments shall be made with the intention of
assuring consistent and continued rendering of quality services and to ensure
prompt availability and accessibility of personnel to physicians in order to
develop constant, familiar and routine working relationships between the
Employed Providers, Contracting Providers and MANAGEMENT SERVICES personnel.

            (d)   Employed Providers. MANAGEMENT SERVICES shall assist the PC in
the administration of any employee benefit plans established by the PC in
compliance with the provisions of Section 1.10 hereof.

            (e)   Managed Care Agreements. MANAGEMENT SERVICES shall negotiate
and administer all managed care agreements on behalf of the PC and shall consult
with the PC on all professional and clinical matters relating thereto.

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                           III. FINANCIAL ARRANGEMENTS

      3.1.  Service Fee. For the services to be provided hereunder by MANAGEMENT
SERVICES, the PC shall pay to MANAGEMENT SERVICES a monthly Service Fee of
$63,800. The parties agree that the Service Fee represents the fair market value
of the services provided by MANAGEMENT SERVICES hereunder and that the parties
shall meet annually to reevaluate the value of services provided by MANAGEMENT
SERVICES and shall establish the fair market value thereof for purposes of this
Section 3.1.

      3.2.  Security Agreement; the PC Expenses. To secure the PC's payment
obligations hereunder, the PC is concurrently herewith entering into a security
agreement, in form acceptable to MANAGEMENT SERVICES, to grant to MANAGEMENT
SERVICES a security interest in the accounts receivable of the PC and all of the
PC's rights to receive payments under managed care contracts. The PC shall
cooperate with MANAGEMENT SERVICES and execute all reasonably necessary
documents in connection with the granting of such security interest.

      All payments on behalf of the PC from Patients and Payors shall be
deposited into one or more Collection Accounts. To the extent the PC receives
any such payments, the PC shall direct such payments to MANAGEMENT SERVICES for
deposit in one or more Collection Accounts.

      3.3.  Arbitration. Any controversy or claim arising out of or relating to
this Agreement or the transactions contemplated hereby, including any
controversy or claim arising out of or relating to the parties' decision to
enter into this Agreement or the transactions contemplated hereby, shall be
settled by binding arbitration. Each party shall select an arbitrator who has at
least three (3) years experience in health care or medical practice management
or in health care or medical practice dispute resolution. The arbitration
proceedings shall be confidential and the arbitrators may issue appropriate
protective orders to safeguard each party's confidential information. Such
protective orders shall be enforceable by any court of competent jurisdiction.
Except as specifically provided in this section, the arbitration shall be
conducted in accordance with the rules of conciliation and arbitration of the
American Arbitration Association. The two arbitrators shall agree upon any issue
no later than thirty (30) days after the date the second arbitrator has been
engaged, and shall take into account the principles and objectives set forth in
paragraph (b) below. If the two arbitrators cannot agree on a determination,
then within five (5) days thereafter the two arbitrators shall select a third
arbitrator, who shall have the same qualifications required for the first two
arbitrators. No later than thirty (30) days after the date the third arbitrator
is engaged, he or she shall determine which of the two positions best satisfies
the provisions of the contract and the intent of the parties, taking into
account the principles and objectives set forth in paragraph (b) below. The
third arbitrator shall have no right to propose a middle ground between the two
or to make any modification of the proposals of either party. The third
arbitrator's determination shall be final and binding on all parties. The cost
and expense of the third arbitrator shall be shared equally between the parties.
If either party fails to engage an arbitrator as required hereunder, the
arbitrator selected by the

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other party shall conduct the arbitration and make the final decision in
accordance with this Section 3.4.

            (b)   The arbitration shall be conducted at the offices of
MANAGEMENT SERVICES or such other mutually acceptable site. In conducting the
arbitration, the arbitrator(s) shall consider the following principles and
objectives of the parties in entering into this Agreement:

                  (i)   The parties contemplate that the PC shall pay MANAGEMENT
SERVICES a flat fee for the fair market value of MANAGEMENT SERVICES' hereunder.

                  (ii)  The parties agree that MANAGEMENT SERVICES shall in no
way provide medical services to Patients.

                  (iii) The parties contemplate an expansion of the Practice by
acquisition or purchase of other Offices and by expansion of the variety of
specialty medical services provided and/or ancillary services provided.

                  IV. REPRESENTATIONS AND WARRANTIES; COVENANTS

      4.1.  Representations and Warranties and Covenants of the PC.

            (a)   The PC hereby represents and warrants to MANAGEMENT SERVICES
as follows:

                  (i)   The PC is and shall remain during the term of this
Agreement a professional corporation duly organized, validly existing and in
good standing under the laws of the State of New York, actively engaged in the
practice of medicine, and possessing full corporate power and authority to own
its properties and to conduct the business in which it engages.

                  (ii)  The PC has full corporate power and authority to execute
and deliver this Agreement and to engage in the transactions and obligations
contemplated by this Agreement. Upon its execution, this Agreement shall
constitute a valid and binding obligation of the PC, enforceable in accordance
with its terms, except as limited by applicable bankruptcy, insolvency,
moratorium, or other similar laws affecting generally the rights of creditors
and by principles of equity. The party executing this Agreement on behalf of the
PC is duly authorized to do so.

                  (iii) The consummation of the transactions contemplated by
this Agreement will not: result in a breach of the terms, provisions, or
conditions of or constitute a default under the Articles of Incorporation,
By-Laws or other enabling or governing instruments of the PC or any agreement to
which the PC is a party or by which it is bound; or, to the best knowledge of
the PC, constitute a violation of any applicable law or regulation.

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            (b)   The PC hereby covenants to MANAGEMENT SERVICES that it shall
not, without the prior written consent of MANAGEMENT SERVICES, take any action
to terminate or nullify, or release any Employed Provider from, the terms of any
noncompetition covenant set forth in any employment agreement between the PC and
such Employed Provider.

      4.2.  Covenants and Warranties of MANAGEMENT SERVICES. MANAGEMENT SERVICES
hereby represents and warrants to the PC as follows:

            (a)   MANAGEMENT SERVICES is and shall remain during the term of
this Agreement a corporation which is duly organized, validly existing and in
good standing under the laws of the State of New York, possessing full corporate
power and authority to own its properties and to conduct the business in which
it engages.

            (b)   MANAGEMENT SERVICES has full corporate power and authority to
execute and deliver this Agreement and to engage in the transactions and
obligations contemplated by this Agreement. Upon its execution, this Agreement
shall constitute a valid and binding obligation of MANAGEMENT SERVICES,
enforceable in accordance with its terms, except as limited by applicable
bankruptcy, insolvency, moratorium, or other similar laws affecting generally
the rights of creditors and by principles of equity. The party executing this
Agreement on behalf of MANAGEMENT SERVICES is duly authorized to do so.

            (c)   The consummation of the transactions contemplated by this
Agreement will not: result in any breach of the terms, provisions or conditions
of or constitute a default under the Certificate of Incorporation, Bylaws or
other enabling or governing instruments of MANAGEMENT SERVICES or any agreement
to which MANAGEMENT SERVICES is a party or by which it is bound; or, to the best
knowledge of MANAGEMENT SERVICES, constitute a violation of any applicable law
or regulation.

                             V. TERM AND TERMINATION

      5.1   Initial and Renewal Term. The term of this Agreement will be for an
initial period of twenty-five (25) years after the Effective Date, and shall be
automatically renewed for successive five (5) year periods thereafter
(collectively, the "Term"), provided that neither MANAGEMENT SERVICES nor the PC
shall have given notice of termination of this Agreement at least one hundred
twenty (120) days before the end of the initial term or any renewal term, or
unless otherwise terminated as provided in Section 5.2 of this Agreement.

      5.2   Termination.

            (a)   Termination by the PC. The PC may immediately terminate this
Agreement at its discretion, upon written notice as follows:

                  (i)   If MANAGEMENT SERVICES becomes insolvent by reason of
its inability to pay its debts as they mature; is adjudicated bankrupt or
insolvent; files a

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petition in bankruptcy, reorganization or similar proceeding under the
bankruptcy laws of the United States or shall have such a petition filed against
it which is not discharged within thirty (30) days; has a receiver or other
custodian, permanent or temporary, appointed for its business, assets or
property, makes a general assignment for the benefit of creditors; has its bank
accounts, property or accounts attached; has execution levied against its
business or property; or voluntarily dissolved or liquidates or has a petition
filed for corporate dissolution and such petition is not dismissed within thirty
(30) days;

                  (ii)  If the MANAGEMENT SERVICES fails to comply with any
material provision of this Agreement, or any other agreement with the PC, and
does not correct such failure within sixty (60) days after written notice of
such failure to comply is delivered by the PC specifying the nature of the
breach in reasonable detail.

            (b)   Termination by MANAGEMENT SERVICES. MANAGEMENT SERVICES may
immediately terminate this Agreement at its discretion, upon written notice as
follows:

                  (i)   If the PC becomes insolvent by reason of its inability
to pay its debts as they mature; is adjudicated bankrupt or insolvent; files a
petition in bankruptcy, reorganization or similar proceeding under the
bankruptcy laws of the United States or shall have such a petition filed against
it which is not discharged within thirty (30) days; has a receiver or other
custodian, permanent or temporary, appointed for its business, assets or
property; makes a general assignment for the benefit of creditors; has its bank
accounts, property or accounts attached; has execution levied against its
business or property; or voluntarily dissolves or liquidates or has a petition
filed for corporate dissolution and such petition is not dismissed within thirty
(30) days; or

                  (ii)  If the PC fails to comply with any material provision of
this Agreement with MANAGEMENT SERVICES, and does not correct such failure
within sixty (60) days after written notice of such failure to comply is
delivered by MANAGEMENT SERVICES specifying the nature of the breach in
reasonable detail.

            (c)   Termination by Agreement. In the event the PC and MANAGEMENT
SERVICES shall mutually agree in writing, this Agreement may be terminated on
the date specified in such written agreement.

            (d)   Legislative, Regulatory or Administrative Change. In the event
there shall be a change in the Medicare or Medicaid statutes, federal statutes,
state statutes, case laws, administrative interpretations, regulations or
general instructions, the adoption of new federal or state legislation, or a
change in any third-party reimbursement system, any of which are reasonably
likely to materially and adversely affect the manner in which either party may
perform or be compensated for its services under this Agreement or which shall
make this Agreement or any related agreements unlawful or unenforceable, or
which would be reasonably likely to subject either party to this Agreement, or
any member, shareholder, officer, director, employee, agent or affiliated
organization to any civil or criminal penalties or administrative sanctions, the
parties shall immediately use their best efforts to enter into a new service
arrangement or basis for

                                     - 12 -
<PAGE>

compensation for the services furnished pursuant to this Agreement that complies
with the law, regulation, or policy, or which minimizes the possibility of such
penalties, sanctions or unenforceability, and that approximates as closely as
possible the economic position of the parties prior to the change. If the
parties are unable to reach a new agreement within a reasonable time, then
either party may submit the issue to arbitration pursuant to Section 3.3 for the
purpose of reaching an alternative arrangement that is equitable under the
circumstances.

      5.3   Effects of Termination. Upon termination of this Agreement, as
provided in this Article V, neither party shall have any further obligations
hereunder except for (i) obligations accruing prior to the date of termination,
including, without limitation, payment of the Service Fee relating to services
provided prior to the termination of this Agreement, (ii) obligations, promises,
or covenants set forth herein that are expressly made to extend beyond the Term,
including, without limitation, insurance, indemnities and non-competition
provisions, which provisions shall survive the expiration or termination of this
Agreement. In effectuating the provisions of this Section 5.3, the PC
specifically acknowledges and agrees that if this Agreement terminates pursuant
to Sections 5.2(b) or (d), MANAGEMENT SERVICES shall continue for a period not
to exceed ninety (90) days to collect and receive on behalf of the PC on an
exclusive basis all cash collections from accounts receivable in existence at
the time this Agreement is terminated, it being understood that (a) such cash
collections may be used to compensate MANAGEMENT SERVICES for services rendered
prior to the termination of this Agreement, (b) MANAGEMENT SERVICES shall not be
entitled to collect accounts receivable after the termination date of this
Agreement is terminated pursuant to Section 5.2(a), and (c) the MANAGEMENT
SERVICES shall deduct for such cash collections any other amounts owed to
MANAGEMENT SERVICES under this Agreement, including, without limitation, any
reasonable costs incurred by MANAGEMENT SERVICES in carrying out the
post-termination procedures and transactions contemplated herein. MANAGEMENT
SERVICES shall remit remaining amounts from such collection activities, if any,
to the PC. Upon the expiration or termination of this Agreement for any reason
or cause whatsoever, MANAGEMENT SERVICES shall surrender to the PC all books and
records pertaining to the PC's Patient medical records and PC Records (as
defined in Section 7.2).

                            VI. RESTRICTIVE COVENANTS

      6.1.  Covenant Regarding Proprietary Information. In the course of the
relationship created pursuant to this Agreement, the PC will have access to
certain methods, trade secrets, processes, ideas, systems, procedures,
inventions, discoveries, concepts, software in various stages of development,
designs, drawings, specifications, models, data, documents, diagrams, flow
charts, research, economic and financial analysis, developments, procedures,
know-how, policy manuals, financial data, form contracts, marketing and other
techniques, plans, materials, forms, copyrightable materials and trade
information regarding the operations of MANAGEMENT SERVICES and/or of its
Affiliates (collectively, the "Protected Parties"). The foregoing, together with
the existence and terms of this Agreement, are referred to in this Agreement as
"Proprietary Information". The PC shall maintain all such Proprietary
Information in strict secrecy and shall not divulge such information to any
third parties, except as may be necessary

                                     - 13 -
<PAGE>

for the discharge of its obligations under this Agreement. The PC shall take all
necessary and proper precautions against disclosure of any Proprietary
Information to unauthorized persons by any of its officers, directors, employees
or agents. All officers, directors, employees and agents of the PC who will have
access to all or any part of the Proprietary Information may be required to
execute an agreement, at the reasonable request of MANAGEMENT SERVICES, valid
under the law of the jurisdiction in which such agreement is executed, and in a
form acceptable to MANAGEMENT SERVICES and its counsel, committing themselves to
maintain the Proprietary Information in strict confidence and not to disclose it
to any unauthorized person or entity. The Protected Parties not party to this
Agreement are hereby specifically made third party beneficiaries of this Section
6.1, with the power to enforce the provisions hereof. Upon termination of this
Agreement for any reason, the PC and each of its Employed Providers and
Contracting Providers shall cease all use of any of the Proprietary Information
and, at the request of MANAGEMENT SERVICES, shall execute such documents as may
be necessary to evidence the PC's abandonment of any claim thereto. The parties
recognize that a breach of this Section 6.1 cannot be adequately compensated in
money damages and therefore agree that injunctive relief shall be available to
the Protected Parties as their respective interests may appear.

      The obligations of the PC under this Section 6.1 shall not apply to
information: (i) which is a matter of public knowledge on or becomes a matter of
public knowledge after the Effective Date of this Agreement, other than as a
breach of the confidentiality terms of this Agreement or as a breach of the
confidentiality terms of any other agreement between the PC and MANAGEMENT
SERVICES or its Affiliates; or (ii) was lawfully obtained by the PC on a
nonconfidential basis other than in the course of performance under this
Agreement and from some entity other than MANAGEMENT SERVICES or its Affiliates
or from some person other than one employed or engaged by MANAGEMENT SERVICES or
its Affiliates, which entity or person has no obligation of confidentiality to
MANAGEMENT SERVICES or its Affiliates.

      6.2.  Covenants Not to Compete During the Term. The parties recognize that
the services to be provided by MANAGEMENT SERVICES shall be feasible only if the
PC operates an active medical practice to which the PC and Employed Providers
devote full time and attention. To that end:

            (a)   Restrictive Covenants by the PC. During the term of this
Agreement, the PC shall not establish, operate or provide physician or other
health care services at any medical office, clinic or other health care facility
providing services substantially similar to those provided by the PC pursuant to
this Agreement anywhere other than at the Offices and as may be approved in
writing by MANAGEMENT SERVICES. The PC shall also not enter into any management
or administrative services agreement or arrangement with any person or entity
other than MANAGEMENT SERVICES without MANAGEMENT SERVICES' prior written
approval.

            (b)   Restrictive Covenants by Employed Providers. All employment
contracts between the PC and its Employed Providers shall name MANAGEMENT
SERVICES as a third-party beneficiary to the contract and shall not be revised
without the prior written consent of MANAGEMENT SERVICES. The contracts shall
include

                                     - 14 -
<PAGE>

noncompetition agreements with its Employed Providers who are physicians, the
substance and form of which is set forth as Exhibit A hereto, and which the PC
will enforce.

      6.3.  Covenant Not to Compete Following Termination. For three (3) years
following the termination of this Agreement by MANAGEMENT SERVICES pursuant to
Section 5.2, the PC shall not enter into any management or administrative
services agreement or any similar arrangement with any person or entity for the
provision of the same or similar services as MANAGEMENT SERVICES provides to the
PC under this Agreement.

      6.4.  Covenant Not to Solicit. During the term of this Agreement and for
three (3) years following the termination of this Agreement, the PC shall not:

            (a)   Directly or indirectly solicit, recruit or hire, or induce any
party to solicit, recruit or hire any person who is an employee of, or who has
entered into an independent contractor arrangement with, MANAGEMENT SERVICES or
any Affiliate of MANAGEMENT SERVICES (excluding any person who performs patient
services);

            (b)   Directly or indirectly, whether for itself or for any other
person or entity, call upon, solicit, divert or take away, or attempt to
solicit, call upon, divert or take away any of MANAGEMENT SERVICES' customers,
business, or clients; or

            (c)   Disrupt, damage, impair or interfere with the business of
MANAGEMENT SERVICES.

      6.5.  Enforcement. MANAGEMENT SERVICES and the PC acknowledge and agree
that since a remedy at law for any breach or attempted breach of the provisions
of this Article VI or of Article VII shall be inadequate, either party shall be
entitled to specific performance and injunctive or other equitable relief in
case of any such breach or attempted breach, in addition to whatever other
remedies may exist by law. All parties hereto also waive any requirement for the
securing or posting of any bond in connection with the obtaining of any such
injunctive or other equitable relief. If any provision of Article VI or Article
VII relating to the restrictive period, scope of activity restricted and/or
other provisions described therein shall be declared by a court of competent
jurisdiction to exceed the maximum time period, scope of activity restricted or
geographical area such court deems reasonable and enforceable under applicable
law, the time period, scope of activity restricted and/or area of restriction
held reasonable and enforceable by the court shall thereafter be the restrictive
period, scope of activity restricted and/or the territory applicable to the
restrictive covenant provisions in this Article VI or Article VII. The
invalidity or non-enforceability of this Article VI or Article VII in any
respect shall not affect the validity or enforceability of the remainder of this
Article VI or Article VII or of any other provisions of this Agreement.

                          VII. INFORMATION AND RECORDS

      7.1.  Ownership of Records. At all times during and after the term of this
Agreement, including any extensions or renewals hereof, all business records,
including

                                     - 15 -
<PAGE>

but not limited to, business agreements, books of account, general
administrative records and all information generated under or contained in the
management information system pertaining to MANAGEMENT SERVICES' obligations
hereunder, and other business information of any kind or nature, except for
Patient medical records and the PC's Records (as defined in Section 7.2), shall
be and remain the sole property of MANAGEMENT SERVICES; provided that after
termination of this Agreement the PC shall be entitled to reasonable access to
such records and information, including the right to obtain copies thereof, for
any purpose related to patient care or the defense of any claim relating to
patient care or the business of MANAGEMENT SERVICES or the PC.

      7.2.  The PC's Business and Financial Records. At all times during and
after the term of this Agreement, the financial, corporate and personnel records
and information relating exclusively to the business and activities of the PC,
as distinguished from the business and activity of MANAGEMENT SERVICES,
hereinafter referred to as "the PC's Records," shall be and remain the sole
property of the PC.

      7.3.  Access to Records. Each party shall be entitled, upon request and
with reasonable advance notice, to obtain access to all records of the other
party directly related to the performance of such party's obligations pursuant
to this Agreement; provided, however, that such right shall not allow for access
to records that must necessarily be kept confidential. Either party, at its
expense, shall have the right to make copies of any records to which it has
access pursuant to this Section.

      7.4.  Confidentiality of Records. MANAGEMENT SERVICES and the PC shall
adopt procedures for maintaining the confidentiality of the records relating to
the operations of MANAGEMENT SERVICES and the PC which do not constitute
Proprietary Information, which information is not otherwise available to third
parties publicly or by law, and shall comply with all applicable federal and
state statutes and regulations relating to such records. Patient medical records
and other privileged Patient information shall not be disclosed or utilized by
the PC or MANAGEMENT SERVICES or their agents or employees except as required or
permitted by applicable laws and regulations.

                               VIII. MISCELLANEOUS

      8.1.  Independent Contractor Status of Parties. In the performance of the
work, duties and obligations under this Agreement, it is mutually understood and
agreed that each party is at all times acting and performing as an independent
contractor with respect to the other and that no relationship of partnership
joint venture or employment is created by this Agreement. Neither party, nor any
other person performing services on behalf of such party pursuant to this
Agreement, shall have any right or claim against the other party for Social
Security benefits, workers' compensation benefits, disability benefits,
unemployment insurance benefits, health benefits, vacation pay, sick leave or
any other employee benefits of any kind.

      8.2.  No Waiver. The waiver by any party to this Agreement of any breach
of any term or condition of this Agreement shall not constitute a waiver of
subsequent

                                     - 16 -
<PAGE>

breaches. No waiver by any party of any provision of this Agreement shall be
deemed to constitute a waiver of any other provision.

      8.3.  Notices. If, at any time after the execution of this Agreement, it
shall become necessary or convenient for one of the parties to serve any notice,
demand or communication upon the other party, such notice, demand, or
communication shall be in writing and shall be served personally, by nationally
recognized overnight courier which provides confirmation of delivery, or by
depositing the same in the United States mail, registered or certified, return
receipt requested, postage prepaid and to such address as either party may have
furnished to the other party in writing as the place for the service of notice.
Any notice so mailed shall be deemed to have been given three (3) days after the
same has been deposited in the United States mail; when delivered if the same
has been given personally; or the next business day if the same has been
delivered to a nationally recognized overnight courier service.

      8.4.  Assignment. Neither party may sell, transfer, assign, or otherwise
convey its rights or obligations under this Agreement without the prior written
consent of the other, which consent shall not be unreasonably withheld.
Notwithstanding the foregoing, MANAGEMENT SERVICES shall have the right to (a)
assign its rights and/or delegate all or any of its obligations to any of its
Affiliates; and/or (b) subcontract some portion of its obligations hereunder to
a third party which is not an Affiliate of MANAGEMENT SERVICES, in each case
without the consent of the PC.

      8.5.  Successors and Assigns. Subject to the provisions of this Agreement
respecting assignment, the terms, covenants and conditions contained herein
shall be binding upon and inure to the benefit of the successors and permitted
assigns of the parties hereto.

      8.6.  Severability. Nothing contained in this Agreement shall be construed
to require the commission of an act contrary to law, and whenever there is any
conflict between any provision of this Agreement and any statute, law, ordinance
or regulation, the latter shall prevail. In such event, and in any case in which
any provision of this Agreement is determined to be in violation of a statute,
law, ordinance or regulation, the affected provision(s) shall be limited only to
the extent necessary to bring it within the requirements of the law and, insofar
as possible under the circumstances, to carry out the purposes of this
Agreement. The other provisions of this Agreement shall remain in full force and
effect, and the invalidity or unenforceability of any provision hereof shall not
affect the validity and enforceability of the other provisions of this
Agreement, nor the availability of all remedies in law or equity to the parties
with respect to such other provisions.

      8.7.  Third Parties. Except as provided in Article VII, nothing in this
Agreement shall be construed to create any duty to, any standard of care with
reference to or any liability to anyone not a party to this Agreement.

      8.8.  Headings. The headings used in this Agreement are for convenience of
reference only and shall have no force or effect in the construction or
interpretation of the provisions of this Agreement.

                                     - 17 -
<PAGE>

      8.9.  Time of the Essence. Time is of the very essence of each and all of
the agreements, covenants and conditions of this Agreement.

      8.10. Governing Law. This Agreement shall be deemed made, executed and
entered into and shall be governed by and construed in accordance with the
internal laws of the State of Florida.

      8.11. Language Construction. The language in all parts of this Agreement
shall be construed, in all cases, according to its fair meaning, and not for or
against either party hereto. The parties acknowledge that each party and its
counsel have reviewed and revised this Agreement and that the normal rule of
construction to the effect that any ambiguities are to be resolved against the
drafting party shall not be employed in the interpretation of this Agreement.

      8.12. Indemnification. The PC shall indemnify, hold harmless and defend
MANAGEMENT SERVICES, its officers, directors, shareholders, employees, agents
and independent contractors (the "MANAGEMENT SERVICES Group") from and against
any and all liabilities, losses, damages, claims, causes of action, and expenses
(including reasonable attorneys' fees and disbursements (a "MANAGEMENT SERVICES
Loss")), caused or asserted to have been caused, directly or indirectly, by or
as a result of the performance of medical services or any other acts or
omissions by MANAGEMENT SERVICES and/or its partners, agents, employees and/or
subcontractors (other than MANAGEMENT SERVICES) during the term hereof except
with respect to any MANAGEMENT SERVICES Loss which is the result of any gross
negligence or willful misconduct by a member of the MANAGEMENT SERVICES Group.
MANAGEMENT SERVICES shall indemnify, hold harmless and defend the PC, its
officers, directors, partners, employees, agents and independent contractors
(the "the PC Group") from and against any and all liabilities, losses, damages,
claims, causes of action, and expenses (including reasonable judgment attorneys'
fees and disbursements) (a "the PC Loss"), caused or asserted to have been
caused, directly or indirectly, by or as a result of the performance of any acts
or omissions by MANAGEMENT SERVICES and/or its shareholders, agents, employees
and/or subcontractors during the term hereof except with respect to any the PC
Loss which is the result of any gross negligence or willful misconduct by a
member of the PC Group.

      8.13. Entire Agreement. This Agreement constitutes the entire agreement
between the parties with respect to the subject matter hereof and supersedes all
prior and contemporaneous agreements, understandings, negotiations and
discussions, whether written or oral, between or among parties regarding the
subject matter of this Agreement.

      8.14. Incorporation by Reference. All exhibits and other attachments to
this Agreement are incorporated by reference into this Agreement by such
reference.

      8.15. Amendments Only in Writing. This Agreement may not be amended or
modified in any respect whatsoever, except by an instrument in writing signed by
the parties hereto.

                                     - 18 -
<PAGE>

      8.16. Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be considered an original and all of which
shall constitute one and the same agreement. This Agreement shall not become
effective until it has been executed by all of the parties hereto.

      8.17. Commercial Impracticability. No party to this Agreement shall be
liable for any failure to perform its obligations hereunder where such failure
results from any cause beyond that party's reasonable control, including, for
example, an act of God, labor disturbance such as a strike or walkout, war,
riot, fire, storm, accident, government regulation or interference, or
mechanical, electronic or communications failure.

      8.18. Election of Remedies. The respective rights of the parties to this
Agreement shall be cumulative.  Each party shall have all other rights and
remedies consistent with this Agreement as law and equity may provide. No
exercise by any party of one right or remedy shall be deemed to be an exclusive
election of rights or remedies.

      8.19. Survival. The provisions of Articles III, IV, V, VI, VII and VIII
shall survive any termination of this Agreement.

      8.20. Third Party Beneficiaries. Except with respect to Affiliates of
MANAGEMENT SERVICES, nothing in this Agreement shall be construed to create any
duty to, any standard of care with reference to, or any liability to any Person
not a party to this Agreement. The Affiliates of MANAGEMENT SERVICES are
intended third party beneficiaries of this Agreement.

      8.21  Affiliate. An "Affiliate" of an entity means (i) any person or
entity directly or indirectly controlled by such entity; (ii) any person or
entity directly or indirectly controlling such entity; (iii) any subsidiary of
such entity if the entity has a fifty percent (50%) or greater ownership
interest in the subsidiary; or (iv) such entity's parent entity if the parent
has a fifty percent (50%) or greater ownership interest in the entity. For
purposes of this Agreement, the PC is not an Affiliate of MANAGEMENT SERVICES.

      IN WITNESS WHEREOF, MANAGEMENT SERVICES and the PC have caused this
Agreement to be executed by their duly authorized respective officers as of the
Effective Date.

Signed and sealed in
the presence of:

/s/ G. DAVID SCHIERING                        NEW YORK RADIATION THERAPY
--------------------------                    MANAGEMENT SERVICES,
Printed name: G. DAVID SCHIERING              INCORPORATED
(witness 1)

                                              By: /s/ Daniel E. Dosoretz
                                                  -----------------------------
/s/ HERBERT ORT                                   Daniel E. Dosoretz, M.D.
--------------------------

                                     - 19 -
<PAGE>

Printed name: HERBERT ORT                           President
(witness 2)

/s/ G. DAVID SCHIERING                        YONKERS RADIATION MEDICAL
-------------------------------               PRACTICE, P.C.
Printed name: G. DAVID SCHIERING
(witness 1)

                                              By: /s/ Daniel E. Dosoretz
                                                  -----------------------------
                                                  Daniel E. Dosoretz, M.D.
                                                  President

/s/ HERBERT ORT
------------------------------
Printed name: HERBERT ORT
(witness 2)

STATE OF FLORIDA          )
                          )
COUNTY OF LEE             )

      The foregoing instrument was acknowledged before me this 13th day of
April, 1999 by Daniel E. Dosoretz, M.D., the President of New York Radiation
Therapy Management Services, Incorporated, a New York corporation organized
under the laws of the State of New York, on behalf of the corporation, and by
Daniel E. Dosoretz, M.D., the President of Yonkers Radiation Medical Practice,
P.C., a New York professional corporation organized under the laws of the State
of New York, on behalf of the corporation.

                                  Signature: /s/ [ILLEGIBLE]
                                             ----------------------------------
                                  Printed name: [ILLEGIBLE]
                                  Notary Public

                                     - 20 -
<PAGE>

                                   EXHIBIT A

                            NONCOMPETITION AGREEMENT

               NON-COMPETITIVE AND RESTRICTIVE AGREEMENTS.

                  A.    During the term of this Agreement and any renewal
period, Physician shall not undertake any professional service except as
directed and authorized by [Employer] and shall not engage in any profession
other than the rendition of the professional services as directed by [Employer].

                  B.    In the event of the termination of this Agreement for
any reason, Physician agrees not to directly or indirectly engage in the
practice of radiation therapy or oncology, or otherwise compete with [Employer],
or any of its physician providers, by practicing as a radiation therapist or
oncologist (i) at any hospital in which physician providers of [Employer]
regularly admit patients, or (ii) within any county in which [Employer] or any
of its Affiliates operate an Office, for a period of two (2) years after the
date of such actual termination of this Agreement. The purpose of this covenant
is to protect [Employer] from the irreparable harm it will suffer if Physician
competes with [Employer] after having been introduced to [Employee's personnel
and patients and after learning special medical procedures used by [Employer]'s
physician providers, [Employer]'s business procedures, office and practice
policies, and the special and confidential professional procedures developed by
[Employer].

                  C.    The parties agree that in the event of any breach or
attempted breach of any of the covenants set out in section B (the "Covenant Not
to Compete"), [Employer] will be entitled to equitable relief by way of
injunction or otherwise, in addition to any remedy at law which may be
available. The parties agree that any violation or threatened violation by
Physician of the Covenant Not to Compete will cause [Employer] to suffer
irreparable harm. The parties agree that [Employer]'s remedy of an injunction is
not the exclusive remedy for breach of the Covenant Not to Compete and that a
court may grant such additional relief as is reasonable.

                  D.    In the event Physician breaches the Covenant Not to
Compete, in addition to the injunctive relief to which [Employer] shall be
entitled under the law, Physician shall immediately repay to [Employer] any
amounts paid by [Employer] pursuant to section 3.B hereof after the termination
of this Agreement, and all severance or termination pay, if any, paid pursuant
to this Agreement. [Employer] may offset against any amounts owed Physician
pursuant to this Agreement any amounts Physician owes [Employer] pursuant to
paragraph E below for breach of the Covenant Not to Compete.

                  E.    In addition to the injunctive relief to which [Employer]
is entitled under the law and in addition to the payments provided for in
paragraph D above and in order to compensate [Employer] for the damages it will
incur in recruiting and compensating a replacement radiation oncologist and for
the lost business it will suffer, in the event of a breach by Physician of the
Covenant Not to Compete, Physician

                                     - 21 -
<PAGE>

shall also pay to [Employer], as liquidated damages, a sum equal to a percentage
of the gross billings of [Employer] for the twelve month period immediately
preceding the termination of this Agreement. The percentage shall be that formed
by dividing the number one by the number equal to the total number of physician
providers of [Employer], including Physician, on the date of termination of this
Agreement. The parties agree that, in the event of the breach by Physician of
the Covenant Not to Compete, the actual amount of damages which would be
incurred by [Employer] would be difficult to ascertain and prove, and that
therefore the liquidated damages sum set forth herein would be reasonable and
appropriate.

                  F.    In the event the Covenant Not to Compete shall be
determined by a court of competent jurisdiction to be unenforceable by reason of
its geographic or temporal restrictions being too great, or by reason that the
range of activities covered is too great, or for any other reason, section B
shall be interpreted to extend over the maximum geographic area, period of time,
range of activities or other restrictions as to which it may be enforceable.

                                     - 22 -
<PAGE>

                  ADDENDUM TO ADMINISTRATIVE SERVICES AGREEMENT
                                    "Yonkers"

      This Addendum (the "Addendum") is entered into as of January 1, 2000, by
and among NEW YORK RADIATION THERAPY MANAGEMENT SERVICES, INCORPORATED, a New
York corporation ("MANAGEMENT SERVICES") and YONKERS RADIATION MEDICAL PRACTICE,
P.C., a New York professional corporation (the "PC"). This Addendum amends
Section 3.1 of the Administrative Services Agreement, dated January 1, 1999,
between the parties (the "Agreement").

      From and after the date hereof, Section 3.1 shall read as follows:

                  3.1.  Service Fee. For the services to be provided hereunder
            by MANAGEMENT SERVICES, the PC shall pay to MANAGEMENT SERVICES a
            monthly Service Fee of $81,250. The parties agree that the Service
            Fee represents the fair market value of the services provided by
            MANAGEMENT SERVICES hereunder and that the parties shall meet
            annually to reevaluate the value of services provided by MANAGEMENT
            SERVICES and shall establish the fair market value thereof for
            purposes of this Section 3.1.

Accepted:                                  NEW YORK RADIATION THERAPY
                                           MANAGEMENT SERVICES, INCORPORATED

                                           By: /s/ David Koeninger
                                               ------------------------------
                                               David Koeninger
                                               Chief Financial Officer

Accepted :                                 YONKERS RADIATION MEDICAL PRACTICE,
                                           P.C.

                                           By: /s/ Daniel E. Dosoretz
                                               -------------------------------
                                               Daniel E. Dosoretz, M.D.
                                               President

<PAGE>

                  ADDENDUM TO ADMINISTRATIVE SERVICES AGREEMENT
                                    "Yonkers"

      This Addendum (the "Addendum") is entered into as of January 1, 2001, by
and among NEW YORK RADIATION THERAPY MANAGEMENT SERVICES, INC., a New York
corporation ("MANAGEMENT SERVICES") and YONKERS RADIATION MEDICAL PRACTICE,
P.C., a New York professional corporation (the "PC"). This Addendum amends
Section 3.1 of the Administrative Services Agreement dated January 1, 1999,
between the parties (the "Agreement") and replaces the Addendum of that same
Section dated January 1, 2000.

      From and after the date hereof, Section 3.1 shall read as follows:

                  3.1.  Service Fee. For the services to be provided hereunder
            by MANAGEMENT SERVICES, the PC shall pay to MANAGEMENT SERVICES a
            monthly Service Fee of $79,166.67. The parties agree that the
            Service Fee represents the fair market value of the services
            provided by MANAGEMENT SERVICES hereunder and that the parties shall
            meet annually to reevaluate the value of services provided by
            MANAGEMENT SERVICES and shall establish the fair market value
            thereof for purposes of this Section 3.1.

Accepted:                                      NEW YORK RADIATION THERAPY
                                               MANAGEMENT SERVICES, INC.

                                               By: /s/ David Koeninger
                                                   -----------------------------
                                                   David Koeninger
                                                   Chief Financial Officer

Accepted :                                     YONKERS RADIATION MEDICAL
                                               PRACTICE, P.C.

                                               By: /s/ Daniel E. Dosoretz
                                                   -----------------------------
                                                   Daniel E. Dosoretz, M.D.
                                                   President

<PAGE>

                  ADDENDUM TO ADMINISTRATIVE SERVICES AGREEMENT
                                    "Yonkers"

      This Addendum (the "Addendum") is entered into as of January 1, 2002, by
and among NEW YORK RADIATION THERAPY MANAGEMENT SERVICES, INC., a New York
corporation ("MANAGEMENT SERVICES") and YONKERS RADIATION MEDICAL PRACTICE,
P.C., a New York professional corporation (the "PC"). This Addendum amends
Section 3.1 of the Administrative Services Agreement dated January 1, 1999,
between the parties (the "Agreement") and replaces the Addendum of that same
Section dated January 1, 2001.

      From and after the date hereof, Section 3.1 shall read as follows:

                  3.1.  Service Fee. For the services to be provided hereunder
            by MANAGEMENT SERVICES, the PC shall pay to MANAGEMENT SERVICES a
            monthly Service Fee of $86,666.67. The parties agree that the
            Service Fee represents the fair market value of the services
            provided by MANAGEMENT SERVICES hereunder and that the parties shall
            meet annually to reevaluate the value of services provided by
            MANAGEMENT SERVICES and shall establish the fair market value
            thereof for purposes of this Section 3.1.

Accepted:                                      NEW YORK RADIATION THERAPY
                                               MANAGEMENT SERVICES, INC.

                                               By: /s/ David Koeninger
                                                   -----------------------------
                                                   David Koeninger
                                                   Chief Financial Officer

Accepted :                                     YONKERS RADIATION MEDICAL
                                               PRACTICE, P.C.

                                               By: /s/ Daniel E. Dosoretz
                                                   -----------------------------
                                                   Daniel E. Dosoretz, M.D.
                                                   President

<PAGE>

                  ADDENDUM TO ADMINISTRATIVE SERVICES AGREEMENT
                                   "Yonkers"

      This Addendum (the "Addendum") is entered into as of January 1, 2003, by
and among NEW YORK RADIATION THERAPY MANAGEMENT SERVICES, INC. a New York
corporation ("MANAGEMENT SERVICES") and YONKERS RADIATION MEDICAL PRACTICE, P.C.
a New York professional corporation (the "PC"). This Addendum amends Section 3.1
of the Administrative Services Agreement dated January 1, 1999, between the
parties (the "Agreement") and replaces the Addendum of that same Section dated
January 1, 2002.

      From and after the date hereof, Section 3.1 shall read as follows:

                  3.1.  Service Fee. For the services to be provided hereunder
            by MANAGEMENT SERVICES, the PC shall pay to MANAGEMENT SERVICES a
            monthly Service Fee of $635,833.33. The parties agree that the
            Service Fee represents the fair market value of the services
            provided by MANAGEMENT SERVICES hereunder and that the parties shall
            meet annually to reevaluate the value of services provided by
            MANAGEMENT SERVICES and shall establish the fair market value
            thereof for purposes of this Section 3.1.

Accepted:                                      NEW YORK RADIATION THERAPY
                                               MANAGEMENT SERVICES, INC.

                                               By: /s/ David Koeninger
                                                   -----------------------------
                                                   David Koeninger
                                                   Chief Financial Officer

Accepted :                                     YONKERS RADIATION MEDICAL
                                               PRACTICE, P.C.

                                               By: /s/ Daniel E. Dosoretz
                                                   -----------------------------
                                                   Daniel E. Dosoretz, M.D.
                                                   President

<PAGE>

                     ADDENDUM TO ADMINISTRATIVE SERVICES AGREEMENT

      This Addendum (the "Addendum") is entered into as of January 1, 2004, by
and among NEW YORK RADIATION THERAPY MANAGEMENT SERVICES, INC., a New York
corporation ("MANAGEMENT SERVICES") and YONKERS RADIATION MEDICAL PRACTICE,
P.C., a New York professional corporation (the "PC"). This Addendum amends
Section 3.1 of the Administrative Services Agreement dated January 1, 1999
between the parties (the "Agreement") and replaces the Addendum of that same
Section dated January 1, 2003.

      From and after the date hereof, Section 3.1 shall read as follows:

                  3.1.  Service Fee. For the services to be provided hereunder
            by MANAGEMENT SERVICES, the PC shall pay to MANAGEMENT SERVICES a
            monthly Service Fee of $562,500.00. The parties agree that the
            Service Fee represents the fair market value of the services
            provided by MANAGEMENT SERVICES hereunder and that the parties shall
            meet annually to reevaluate the value of services provided by
            MANAGEMENT SERVICES and shall establish the fair market value
            thereof for purposes of this Section 3.1.

            Accepted:                          NEW YORK RADIATION THERAPY
                                               MANAGEMENT SERVICES, INC.

                                               By: /s/ David Koeninger
                                                   -----------------------------
                                                   David Koeninger
                                                   Vice President and CFO

            Accepted :                         YONKERS RADIATION MEDICAL
                                               PRACTICE, P.C.

                                               By: /s/ Daniel E. Dosoretz
                                                   -----------------------------
                                                   Daniel E. Dosoretz, M.D.
                                                   President