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                                                                   EXHIBIT 10.11

                              EMPLOYMENT AGREEMENT

THIS AGREEMENT, is made and entered into this 1st day of January, 2003, by and
between Fresenius Medical Care North America ("FMCNA" or the "EMPLOYER"), with
principal offices located at 95 Hayden Avenue, Lexington, MA 02420 and Ronald J.
Kuerbitz ( "EMPLOYEE") currently residing at 47 Park Avenue, Wellesley, MA
02481.

WITNESSETH:

WHEREAS, FMC desires to employ EMPLOYEE as Senior Vice President, Chief
Administrative Officer, of FMCNA and its affiliated corporations in North
America, 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. FMCNA hereby employs EMPLOYEE as Senior Vice President and
      Chief Administrative Officer, 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 January 1, 2003 and
      continue thereafter, unless terminated in accordance with the provisions
      hereinafter stated.

3.    DUTIES AND RESPONSIBILITIES. EMPLOYEE shall serve full time as FMCNA's
      Senior Vice President and Chief Administrative Officer. EMPLOYEE shall
      report directly to the Chief Executive Officer of FMCNA. 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 Four Hundred Fifty Thousand Dollars ($450,000) per year, (the
      "Base Salary"), payable in accordance with FMCNA'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 FMCNA, EMPLOYEE
      shall be entitled to participate in FMCNA'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 FMCNA.
      EMPLOYEE will be in the FMCNA Management Bonus Plan at a target level
      bonus of fifty percent (50%) and the maximum bonus is one hundred percent
      (100%) 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.

c)    Stock Plan. EMPLOYEE shall be eligible 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"),
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      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 FMCNA'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 Two Thousand Dollars ($2,000) 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 under
      the Executive Vacation Policy 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 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
      which results in an arrest or indictment; (ii) deliberate and continual
      refusal to satisfactorily perform employment duties reasonably requested
      by the EMPLOYER after thirty (30) 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 EMPLOYER'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 EMPLOYER which has substantial effect
      on the EMPLOYER; (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


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      covenants set forth in Section 7 below. EMPLOYEE will be considered to
      have been terminated for "Cause" if the EMPLOYER determines that EMPLOYEE
      engaged in an act constituting "Cause," regardless of whether the
      individual terminates employment voluntarily or 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 FMCNA written notice specifying
      the manner in which he believes FMCNA has breached this Agreement and
      FMCNA 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.

      Additionally, this Agreement may be terminated by EMPLOYEE, if there is a
      reduction in EMPLOYEE's responsibilities or FMCNA experiences a change in
      control defined as any of the following: i) the transfer (whether by sale,
      dividend, exchange, lease, merger, consolidation or otherwise) of greater
      than fifty percent (50%) of the voting power of FMCNA; ii) the transfer
      (whether by sale, dividend, exchange, lease, merger, consolidation or
      otherwise) of all or substantially all the assets or stock of FMCNA; or
      iii) any other action which results in persons other than the current
      majority shareholders of FMCNA, having the voting power to direct the
      management of FMCNA or if FMCNA relocates its corporate headquarters more
      than fifty (50) miles from its present location in Lexington,
      Massachusetts.

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 EMPLOYMENT.

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; 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. Upon any such
            termination, EMPLOYEE shall have the right to exercise his Vested
            Stock Options in accordance with the terms of the plan.

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 twenty-four (24) 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 FMCNA 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 of 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.


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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 the EMPLOYER.
      Confidential Information means all information related to the present or
      planned business of FMCNA that has not been released publicly by
      authorized representatives of FMCNA, 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 FMCNA at any time and in any manner, except as
      required in the course of his employment with FMCNA or with the express
      written authority of FMCNA.

      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 FMCNA for
      any reason or the end of the period during which EMPLOYEE continues to
      receive salary continuation after leaving the employment of FMCNA,
      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 FMCNA 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 FMCNA; and

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

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

8.    ENFORCEMENT OF COVENANTS.

a)    Forfeiture of Compensation. EMPLOYEE agrees that if 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 in addition to
      remedies otherwise available to it at law or equity, to injunctions, both
      preliminary and permanent, enjoining or retraining such breach or
      anticipatory breach

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 forth in Section 7


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      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.    FMCNA DOCUMENTS AND EQUIPMENT. All documents and equipment relating to the
      business of FMCNA, whether prepared by EMPLOYEE or otherwise coming into
      EMPLOYEE's possession, are the exclusive property of FMCNA, 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 FMCNA
      when EMPLOYEE leaves the employment of FMCNA.

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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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.

                                NATIONAL MEDICAL CARE, INC. D/B/A
                                FRESENIUS MEDICAL CARE
                                NORTH AMERICA,
WITNESS                         EMPLOYER

/s/Brian O'Connell              By:/s/Ben J. Lipps                       6/20/03
---------------------------        ----------------------------          -------
                                   Ben J. Lipps, President and            (DATE)
                                   Chief Executive Officer

WITNESS                         RONALD J. KUERBITZ



/s/Brian O'Connell              /s/Ronald J. Kuerbitz                    6/20/03
---------------------------     -------------------------------          -------
                                (Employee Signature)                      (DATE)


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