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                                                                   Exhibit 10.15


                              EMPLOYMENT AGREEMENT

THIS AGREEMENT, is made and entered into this 1st day of July 2002, by and
between Fresenius Medical Care North America ("FMC" or the "COMPANY"), with
principal offices located at 95 Hayden Avenue, Lexington, MA 02420 and John F.
Markus ("EMPLOYEE") currently residing at 228 Ponus Ridge Road, New Canaan, CT
06840.

WITNESSETH:

WHEREAS, FMC and EMPLOYEE desire to extend the employment term of EMPLOYEE as
Senior Vice President of Corporate Compliance and Government Affairs through
June 30, 2003; and

WHEREAS, the parties hereto desire to express the terms and conditions of such
employment.

NOW THEREFORE, it is understood and agreed to between the parties as follows:

1.    RETENTION, DUTIES AND RESPONSIBILITIES. FMC hereby employs EMPLOYEE as
      Senior Vice President of Corporate Compliance and Government Affairs, and
      EMPLOYEE hereby accepts such employment, in each case upon the terms and
      conditions of this Agreement. EMPLOYEE shall provide services
      (approximately 1,040 hours during the term of this agreement) at such
      times and places as the parties shall reasonably agree, provided that
      COMPANY shall in no event require EMPLOYEE to provide services for more
      than one half of the time contracted hereunder at a location outside
      EMPLOYEE's primary residence or its vicinity. EMPLOYEE shall report to the
      COMPANY'S Chief Executive Officer EMPLOYEE shall to the best of his
      ability and experience competently, loyally, diligently and
      conscientiously perform all of the duties and obligations expressly or
      implicitly required under this Agreement. EMPLOYEE further agrees that, in
      conducting business in the interest of the COMPANY, he will not engage in,
      knowingly permit others under his control to carry on, or induce others to
      engage in any practice or commit any acts in violation of any federal or
      state or local law or ordinance.

2.    TERM. The term of this Agreement shall commence as of July 1, 2002 and
      shall terminate as of June 30, 2003 in accordance with the provisions
      hereinafter stated unless extended in writing by mutual agreement of the
      parties.

3.    COMPENSATION AND BENEFITS.

      a.    COMPANY shall pay EMPLOYEE a salary of $344,500 during the term of
            this Agreement, payable in accordance with FMC's payroll procedures,
            subject to customary withholding and employment taxes. EMPLOYEE
            shall not participate in FMC's Incentive Compensation Program or any
            other such incentive compensation plans.

      b.    Benefit Programs. EMPLOYEE shall continue to be eligible to
            participate in the group employee benefits programs at the senior
            executive level as now established or which subsequently become
            available.

      c.    Life Insurance. EMPLOYEE will be provided with life insurance in
            accordance with FMC's policy, currently capped at Four Hundred
            Thousand Dollars ($400,000). EMPLOYEE will be provided with the
            opportunity to purchase supplemental life insurance of an additional
            Six Hundred Thousand Dollars ($600,000) beyond the current policy of
            coverage at his own expense, with proof of good health.

      d.    Expenses. EMPLOYEE will be reimbursed for travel and other expenses
            related to the performance of his duties under the Agreement and in
            accordance with the COMPANY's policies.

4.    Termination of Agreement. This Agreement may be terminated under the
      following circumstances:

      a.    Death. EMPLOYEE's employment hereunder shall terminate upon his
            death.
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      b.    Total Disability. The COMPANY may terminate EMPLOYEE's employment
            hereunder upon EMPLOYEE becoming "Totally Disabled." For purposes of
            this Agreement, EMPLOYEE shall be "Totally Disabled" if EMPLOYEE is
            physically or mentally incapacitated so as to render EMPLOYEE
            incapable of performing EMPLOYEE's usual and customary duties under
            this Agreement. EMPLOYEE's receipt of Social Security disability
            benefits or disability benefits under a Company-sponsored long-term
            disability plan shall be deemed conclusive evidence of Total
            Disability for purpose of this Agreement; provided, however, that in
            the absence of EMPLOYEE's receipt of such Social Security or
            long-term disability benefits, the Company's Board of Directors may,
            in its reasonable discretion (but based upon medical evidence),
            determine that EMPLOYEE is Totally Disabled.

      c.    Voluntary Termination. COMPANY or EMPLOYEE may terminate EMPLOYEE's
            employment hereunder at any time after providing written notice to
            the other party. The EMPLOYEE is required to give the COMPANY at
            least thirty (30) days written notice if he wishes to terminate his
            employment pursuant to this provision.

      d.    Termination by the COMPANY for Cause. The COMPANY may terminate
            EMPLOYEE's employment for Cause at any time after providing written
            notice to EMPLOYEE. For purposes of this Agreement, the term "Cause"
            shall mean, with respect to the EMPLOYEE, any of the following: (i)
            commission by EMPLOYEE of a felony or of any criminal act involving
            moral turpitude; (ii) deliberate and continual refusal to
            satisfactorily perform employment duties reasonably requested by the
            COMPANY after 20 days' written notice by certified mail of such
            failure to perform, specifying that the failure constitutes cause
            (other than as a result of vacation, sickness, illness or injury);
            (iii) fraud or embezzlement determined in accordance with the
            COMPANY's normal, internal investigative procedures consistently
            applied in comparable circumstances to employees; (iv) gross
            misconduct or gross negligence in connection with the business of
            the COMPANY which has substantial effect on the COMPANY; (v) failure
            to obtain and maintain in good order any licenses required for
            EMPLOYEE to perform his duties under this Agreement; or (vi) a
            breach of any of the covenants set forth in Section 6 below.
            EMPLOYEE will be considered to have been terminated for "Cause" if
            the COMPANY determines that EMPLOYEE engaged in an act constituting
            "Cause," regardless of whether the individual terminates retention
            voluntarily or retention is terminated involuntarily, and regardless
            of whether the individual's termination initially was considered to
            have been for "Cause."

      e.    Termination by EMPLOYEE for Cause. This Agreement may be terminated
            by EMPLOYEE in the event of a breach by FMC of any of its
            obligations under this Agreement, provided EMPLOYEE gives FMC
            written notice specifying the manner in which he believes FMC has
            breached this Agreement and FMC has thirty (30) days from receipt of
            such notice to cure such breach, or in the case of other than a
            non-payment of money breach, if such breach cannot be cured within
            thirty (30) days, to commence a good faith effort to cure.

      f.    Notice of Termination. Any termination by the COMPANY or the
            EMPLOYEE under this Agreement shall be communicated by notice of
            termination to the other party hereto. For purposes of this
            Agreement, a Notice of Termination shall mean a notice in writing
            which shall indicate the specific termination provision in this
            Agreement relied upon to terminate EMPLOYEE's employment and shall
            set forth in reasonable detail the facts and circumstances claimed
            to provide a basis for termination of EMPLOYEE's employment under
            the provision so indicated.

5.    COMPENSATION FOLLOWING TERMINATION OF RETENTION.

      a.    Under all circumstances, upon termination the EMPLOYEE shall be
            entitled to receive:

            (i)   Any accrued but unpaid salary for services rendered to the
                  date of termination; and

            (ii)  Any benefits to which EMPLOYEE may be entitled upon
                  termination pursuant to the plans, policies and arrangements
                  referred to in Section 4 hereof shall be determined and paid
                  in accordance with the terms of such plans, policies and
                  arrangements.


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      b.    In the event that EMPLOYEE's employment hereunder is voluntarily
            terminated by the COMPANY in accordance with Section 5(c), or in the
            event that EMPLOYEE's retention hereunder is terminated by the
            EMPLOYEE in accordance with Section 5(e), the EMPLOYEE shall also be
            entitled to receive the balance of the salary payments remaining
            under the specified term of this Agreement. At EMPLOYEE's option, he
            may elect to receive such salary continuation in a lump sum or under
            COMPANY's or in accordance with COMPANY's standard payroll
            procedures. In the event EMPLOYEE elects to receive salary
            continuation payments in accordance with COMPANY's standard payroll
            procedures, EMPLOYEE shall receive continuation at COMPANY's expense
            of any coverage under COMPANY's life, medical and dental plans on
            the same basis and to the same extent as the coverage provided
            during EMPLOYEE's employment. In the event EMPLOYEE elects to
            receive salary continuation in a lump sum, EMPLOYEE shall have the
            right to elect to pay for such coverage under COBRA.

      c.    Any stock options or other awards will continue to vest in
            accordance with the terms of the award and the plan pursuant to
            which it was made. EMPLOYEE shall have three (3) years from any such
            termination to exercise his Vested Stock Options. Should he fail to
            exercise these options within this period, they will be forfeited at
            the end of the period.

6.    NON-DISCLOSURE/NON COMPETITION AGREEMENT. EMPLOYEE acknowledges that
      during the term of this Agreement, EMPLOYEE will have access to and become
      acquainted with Confidential Information of the COMPANY. Confidential
      Information means all information related to the present or planned
      business of FMC that has not been released publicly by authorized
      representatives of FMC, and shall include but not be limited to, trade
      secrets and know-how, inventions, marketing and sales programs, EMPLOYEE,
      customer, patient and supplier information, information from patient
      medical records, financial data, pricing information, regulatory approval
      and reimbursement strategies, data, operations and clinical manuals.

      EMPLOYEE agrees not to use or disclose, directly or indirectly, any
      Confidential Information of FMC at any time and in any manner, except as
      required in the course of his employment with FMC or with the express
      written authority of FMC.

      EMPLOYEE understands that his non-disclosure obligations will continue
      following termination of this Agreement.

      EMPLOYEE agrees that during the term of his retention, and for a period of
      one (1) year immediately after termination of this Agreement, EMPLOYEE
      will not directly or indirectly for his own benefit or the benefit of
      others:

      a.    render services for a competing organization in connection with
            competing products as an EMPLOYEE, employee, officer, agent, broker,
            EMPLOYEE, partner, stockholder (except that EMPLOYEE may own three
            percent (3%) or less of the equity securities of any publicly-traded
            company);

      b.    hire or seek to persuade any employee of FMC to discontinue
            employment or to become employed in any competing organization or
            seek to persuade any independent contractor or supplier to
            discontinue its relationship with FMC; and

      c.    solicit, direct, take away or attempt to take away any business or
            customers of FMC.

      Nothing in this Agreement would preclude EMPLOYEE from working for a
      competitor of FMC's subsequent to termination of this Agreement provided
      EMPLOYEE will not be engaged, directly or indirectly, in any business in
      which FMC is actively engaged at the time of EMPLOYEE's termination or in
      any new business which FMC is in the process of setting up in which
      EMPLOYEE had direct involvement while employed by FMC. EMPLOYEE also
      agrees to inform FMC of any such employment with a competitor before
      beginning such employment.


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In consideration of the promises made by the EMPLOYEE under this Section, the
COMPANY agrees to pay EMPLOYEE the sum of $172,000, payable in four equal
installments of $43,000 at the end of each calendar quarter following
termination, except where such termination occurs pursuant to Section 4 (d).

7.    ENFORCEMENT OF COVENANTS.

      a.    Termination of Retention and Forfeiture of Compensation. EMPLOYEE
            agrees that in the event that the COMPANY determines that EMPLOYEE
            has breached any of the covenants set forth in Section 6 hereof
            during EMPLOYEE's employment, the COMPANY shall have the right to
            terminate EMPLOYEE's retention for "Cause."

            In addition, EMPLOYEE agrees that if the COMPANY determines that
            EMPLOYEE has breached any of the covenants set forth in Section 6 at
            any time, the COMPANY shall have the right, notwithstanding anything
            herein to the contrary, to discontinue any or all amounts otherwise
            payable to EMPLOYEE hereunder. Such termination of retention or
            discontinuance of payments shall be in addition to and shall not
            limit any and all other rights and remedies that the COMPANY may
            have against EMPLOYEE.

      b.    Right to Injunction. EMPLOYEE acknowledges that a breach of the
            covenants set forth in Section 6 hereof will cause irreparable
            damage to the COMPANY with respect to which the COMPANY's remedy at
            law for damages will be inadequate. Therefore, in the event of
            breach or anticipatory breach of the covenants set forth in this
            section by EMPLOYEE, EMPLOYEE and the COMPANY agree that the COMPANY
            shall be entitled to the following particular forms of relief, in
            addition to remedies otherwise available to it at law or equity: (i)
            injunctions, both preliminary and permanent, enjoining or
            restraining such breach or anticipatory breach and EMPLOYEE hereby
            consents to the issuance thereof forthwith and without bond by any
            court of competent jurisdiction; and (ii) recovery of all reasonable
            sums expended and costs, including reasonable attorney's fees,
            incurred by the COMPANY to enforce the covenants set forth in this
            section.

      c.    Separability of Covenants. The covenants contained in Section 6
            hereof constitute a series of separate covenants, one for each
            applicable State in the United States and the District of Columbia,
            and one for each applicable foreign country. If in any judicial
            proceeding, a court shall hold that any of the covenants set forth
            in Section 6 exceed the time, geographic, or occupational
            limitations permitted by applicable laws, EMPLOYEE and the COMPANY
            agree that such provisions shall and are hereby reformed to the
            maximum time, geographic, or occupational limitations permitted by
            such laws. Further, in the event a court shall hold unenforceable
            any of the separate covenants deemed included herein, then such
            unenforceable covenant or covenants shall be deemed eliminated from
            the provisions of this Agreement for the purpose of such proceeding
            to the extent necessary to permit the remaining separate covenants
            to be enforced in such proceeding. EMPLOYEE and the COMPANY further
            agree that the covenants in Section 6 shall each be construed as a
            separate agreement independent of any other provisions of this
            Agreement, and the existence of any claim or cause of action by
            EMPLOYEE against the Company whether predicated on this Agreement or
            otherwise, shall not constitute a defense to the enforcement by the
            Company of any of the covenants in Section 6.

8.    FMC DOCUMENTS AND EQUIPMENT. All documents and equipment relating to the
      business of FMC, whether prepared by EMPLOYEE or otherwise coming into
      EMPLOYEE's possession, are the exclusive property of FMC, and must not be
      removed from the premises of FMC except in the course of providing
      services under this Agreement. Any such documents and equipment must be
      returned to FMC when EMPLOYEE upon termination of this Agreement.

9.    WITHHOLDING OF TAXES. The COMPANY may withhold from any compensation and
      benefits payable under this Agreement federal, state, local, or other
      taxes.


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10.   ENTIRE AGREEMENT AND AMENDMENTS. This Agreement shall constitute the
      entire agreement between the parties and supersedes all existing
      agreements between them, whether oral or written, with respect to the
      subject matter hereof except for the terms of applicable benefit plans and
      stock option awards. Any waiver, alteration, or modification of any of the
      provisions of this Agreement, or cancellation or replacement of this
      Agreement shall be accomplished in writing and signed by the respective
      parties.

11.   NOTICES. Any notice, consent, request or other communication made or given
      in connection with this Agreement shall be in writing and shall be deemed
      to have been duly given when delivered or mailed by registered or
      certified mail, return receipt requested, to those listed below at their
      following respective addresses or at such other address as each may
      specify by notice to the others:

                    To the COMPANY:

                              Fresenius Medical Care North America
                              Corporate Headquarters
                              Two Ledgemont Center
                              95 Hayden Avenue
                              Lexington, MA 02420-9192
                              Attention: Vice President, Human Resources

                    To EMPLOYEE:

                              228 Ponus Ridge Road
                              New Canaan, CT 06840

12.   GOVERNING LAW. This Agreement shall be construed in accordance with, and
      the laws of the Commonwealth of Massachusetts shall govern the rights of
      the parties.

13.   SEPARABILITY. If any term or provision of this Agreement is declared
      illegal or unenforceable by any court of competent jurisdiction and cannot
      be modified to be enforceable, such term or provision shall immediately
      become null and void, leaving the remainder of this Agreement in full
      force and effect.

IN WITNESS WHEREOF, the parties have caused this Agreement to be executed by the
undersigned duly authorized persons as of the day and year first stated above.


NATIONAL MEDICAL CARE, INC. d/b/a
FRESENIUS MEDICAL CARE
NORTH AMERICA


By:  /s/ Ronald J. Kuerbitz                             5/15/02
     ----------------------------------                ----------
     Ronald J. Kuerbitz                                  (DATE)
     Senior Vice President and
     General Counsel

     /s/ John F. Markus                                 5/24/02
---------------------------------------                ----------
     John F. Markus                                      (DATE)


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