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                                                                   EXHIBIT 10.13

                              EMPLOYMENT AGREEMENT

THIS AGREEMENT, is made and entered into this 15th day of March 2002, by and
between Fresenius Medical Care North America ("FMC" or the "EMPLOYER"), with
principal offices located at 95 Hayden Avenue, Lexington, MA 02420 and Robert
"Rice" M. Powell, Jr. ("EMPLOYEE") currently residing at 59 Rocky Brook Road,
North Andover, MA 01845.

WITNESSETH:

WHEREAS, FMC desires to employ EMPLOYEE as Senior Vice President and President
of the Dialysis Products Division , 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.    EMPLOYMENT. FMC hereby employs EMPLOYEE as Senior Vice President and
      President of Dialysis Products Division, and EMPLOYEE hereby accepts the
      employment upon the terms and conditions of this Agreement.

2.    TERM. The term of this Agreement shall commence as of March 15, 2002 and
      continue thereafter, unless terminated in accordance with the provisions
      hereinafter stated. THE INITIAL TERM SHALL BE RENEWED BY A SUCCESSIVE ONE
      (1) YEAR PERIOD UNLESS EITHER PARTY GIVES WRITTEN NOTICE OF NON-RENEWAL TO
      THE OTHER PARTY AT LEAST THIRTY (30) DAYS PRIOR TO ANY TERMINATION DATE.
      THE INITIAL TERM AND ANY SUBSEQUENT RENEWAL PERIODS SHALL BE CALLED THE
      "EMPLOYMENT TERM."

3.    DUTIES AND RESPONSIBILITIES. EMPLOYEE shall serve full time as Senior Vice
      President and President of the Dialysis Products Division and in this
      position, EMPLOYEE will have full management responsibility for Dialysis
      Products Division, Spectra Renal Management and Corporate Information
      Services . EMPLOYEE shall report directly to the 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 EMPLOYER, 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.

4.    COMPENSATION AND BENEFITS.

      a)    Base Salary. EMPLOYER shall pay EMPLOYEE for all services rendered a
            base salary of Three Hundred Fifty Thousand Dollars and No Cents
            ($350,000) per year, (the "Base Salary"), payable in accordance with
            FMC's payroll procedures, subject to customary withholding and
            employment taxes. At the end of each year of employment hereunder,
            EMPLOYEE's performance for the prior year shall be reviewed and
            evaluated. If EMPLOYEE's performance is satisfactory, EMPLOYEE shall
            receive an increase in his base salary commensurate with level of
            achievement.

      b)    Incentive Compensation. During EMPLOYEE's employment with FMC,
            EMPLOYEE shall be entitled to participate in FMC's Management Bonus
            Plan and any other such incentive compensation plans as are now
            available or may become available to other similarly positioned
            senior executives of FMC. EMPLOYEE will be in the senior executive
            eligibility Level I, wherein the target level bonus is forty percent
            (40%) and the maximum bonus is eighty percent (80%) of base salary.
            Funding for the plan is based upon attainment of specific individual
            and company financial objectives. EMPLOYEE's entitlement to a bonus
            under the Management Bonus Plan will be governed by terms of that
            Plan.
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      c)    Stock Plan. EMPLOYEE shall be eligibly to participate in the current
            Fresenius Medical Care AG Stock Incentive Plan, and any future stock
            incentive plan (individually a "Stock Plan" and collectively, the
            "Stock Plans"), subject to IRS approval of such respective Stock
            Plans. In addition to the existing options to purchase Fresenius
            Medical Care AG Preference Shares previously granted to EMPLOYEE
            (the "Existing Options"), EMPLOYEE shall be eligible to receive
            additional option grants in amounts as and if approved by the
            Fresenius Medical Care AG Managing Board.

      d)    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.

      e)    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.

      f)    Automobile. EMPLOYEE will be provided with a company car allowance
            of Seven Hundred Dollars ($700) paid monthly and treated as ordinary
            income.

      g)    Financial Planning/Tax Preparation. EMPLOYEE will be provided with
            an allowance of One Thousand Dollars ($1,000) to be paid based upon
            submitted documentation of expenses incurred as a result of
            financial planning assistance or income tax preparation.
            Reimbursement will be treated as ordinary income.

      h)    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 EMPLOYER's policies.

      i)    Vacation/PTO. EMPLOYEE shall be allowed to carry-over up to two
            hundred (200) hours from year-to-year without losing such time.
            EMPLOYEE shall also accrue PTO days at the maximum available to
            senior executives which currently provides for thirty (30) days of
            PTO per year.

5.    TERMINATION OF EMPLOYMENT. EMPLOYEE's employment hereunder may be
      terminated under the following circumstances:

      a)    Death. EMPLOYEE's employment hereunder shall terminate upon his
            death.

      b)    Total Disability. The EMPLOYER 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. EMPLOYER 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 EMPLOYER at
            least thirty (30) days written notice if he wishes to terminate his
            employment pursuant to this provision.

      d)    Termination by the EMPLOYER for Cause. The EMPLOYER may terminate
            EMPLOYEE's employment for Cause at any time after providing thirty
            (30) days' written notice to EMPLOYEE. Such notice shall specify in
            reasonable detail the nature of the Cause, and during such thirty
            (30) day period, EMPLOEE shall have the opportunity to cure the
            stated Cause, if at all possible. If EMPLOYEE fails to cure a state
            Cause, or if such Cause cannot be cured, EMPLOYEE's employment
            hereunder shall terminate at the end of the thirty (30) day period,
            but without prejudice to EMPLOYEE's right to contest the existence
            of any


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            stated Cause or to contest the fact that the Cause has not been
            cured. For purposes of this Agreement, the term "Cause" shall mean,
            with respect to the EMPLOYEE, any of the following: (i) conviction
            of EMPLOYEE of a felony; (ii) deliberate and continual refusal to
            satisfactorily perform employment duties reasonably requested by the
            EMPLOYER; (iii) fraud or embezzlement determined in accordance with
            the EMPLOYER's normal, internal investigative procedures
            consistently applied in comparable circumstances to EMPLOYEES; (iv)
            failure to obtain and maintain in good order any licenses required
            for EMPLOYEE to perform his duties under this Agreement; or (v) a
            breach of any of the covenants set forth in Section 7 below.

      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 EMPLOYER 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.

6.    COMPENSATION FOLLOWING TERMINATION OF RETENTION.

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

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

            (ii)  Accrued PTO; and

            (iii) 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. EMPLOYEE shall have one (1) year from any such
                  termination to exercise his Vested Stock Option. Should he
                  fail to exercise these options within this period, they will
                  be forfeited at the end of that period.

      b)    In the event that EMPLOYEE's employment hereunder is voluntarily
            terminated by the EMPLOYER in accordance with Section 5(c), or in
            the event that EMPLOYEE's employment hereunder is terminated by the
            EMPLOYEE in accordance with Section 5(e), the EMPLOYEE shall also be
            entitled to receive:

                  (i)   A payment equal to eighteen (18) months Base Salary, at
                        the rate in effect on the date of termination of
                        employment, such amount to be paid as salary
                        continuation with benefits. EMPLOYEE may request and FMC
                        will agree that any remaining salary continuation be
                        paid in a lump sum. If a lump sum is selected, all
                        benefits entitlement will cease as of the date of such
                        payment; and

                  (ii)  A pro-rated portion of the EMPLOYEE's annual bonus based
                        upon termination or work date.

      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. If the terms of any award and governing plan are
            silent with respect to termination of employment, such award will
            lapse immediately upon such termination.

7.    NON-DISCLOSURE/NON COMPETITION AGREEMENT. EMPLOYEE acknowledges that
      during the term of employment with EMPLOYER, he will have access to and
      become acquainted with Confidential Information of


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      the EMPLOYER. 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 his termination of employment.

      EMPLOYEE agrees that during the term of his employment, and for a period
      of one (1) year immediately after, he leaves the employment of FMC for any
      reason or the end of the period during which EMPLOYEE continues to receive
      salary continuation after leaving the employment of FMC, whichever is
      greater, 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, officer, agent, broker,
            consultant, 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 EMPLOYEE's employment
      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.

8.    ENFORCEMENT OF COVENANTS.

      a)    EMPLOYEE agrees that if the EMPLOYER determines that EMPLOYEE has
            breached any of the covenants set forth in Section 7 at any time,
            the EMPLOYER shall have the right, notwithstanding anything herein
            to the contrary, to discontinue any or all amounts otherwise payable
            to EMPLOYEE hereunder. Such termination of employment or
            discontinuance of payments shall be in addition to and shall not
            limit any and all other rights and remedies that the EMPLOYER may
            have against EMPLOYEE.

      b)    Right to Injunction. EMPLOYEE acknowledges that a breach of the
            covenants set forth in Section 7 hereof will cause irreparable
            damage to the EMPLOYER with respect to which the EMPLOYER'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 EMPLOYER agree that the
            EMPLOYER shall be entitled to the following particular forms of
            relief, in addition to remedies otherwise available to it at law or
            equity: 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.

      c)    Separability of Covenants. The covenants contained in Section 7
            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


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            forth in Section 7 exceed the time, geographic, or occupational
            limitations permitted by applicable laws, EMPLOYEE and the EMPLOYER
            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 EMPLOYER further
            agree that the covenants in Section 7 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 7.

9.    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 as required in the course of
      employment. Any such documents and equipment must be returned to FMC when
      EMPLOYEE leaves the employment of FMC.

10.   WITHHOLDING OF TAXES. The EMPLOYER may withhold from any compensation and
      benefits payable under this Agreement all applicable federal, state,
      local, or other taxes.

11.   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. 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.

12.   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 Employer:

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

                     To Employee:

                           At the address for Employee set forth above

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


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<PAGE>
14.   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.

<TABLE>
<S>                                     <C>                                                <C>
                                        NATIONAL MEDICAL CARE, INC. D/B/A
                                        FRESENIUS MEDICAL CARE
WITNESS                                 NORTH AMERICA, EMPLOYER


 /s/ Lorraine Gettings                  By: /s/ Ben J. Lipps                               6/6/02
----------------------------                ----------------------------------             ------
                                            Ben J. Lipps                                   (DATE)
                                            Chief Executive Officer

WITNESS                                 ROBERT "RICE" M. POWELL, JR.

  /s/ Brian O'Connell                   /s/ Robert Maurice Powell                          5/29/02
----------------------------            --------------------------------------             -------
                                        (Employee Signature)                               (DATE)
</TABLE>


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