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                                                                   Exhibit 10.20


                              SEPARATION AGREEMENT

     This Agreement is entered into as of this 30th day of June, 1999 (the
"Effective Date") between William F. Grieco ("Mr. Grieco"), who currently
resides at 115 Marlborough Street, Boston, Massachusetts, 02116, and Fresenius
Medical Care Holdings, Inc., d/b/a Fresenius Medical Care North America, with
its principal offices located at 95 Hayden Avenue, Lexington, Massachusetts
02420 ("FMC" or the "Company"); and Fresenius Medical Care AG, with its
principal offices located at Else-Kroner-Strasse 1, 61352 Bad Homburg v.d.H.,
Germany ("FMCAG").

                              W I T N E S S E T H :

     WHEREAS, on November 11, 1998, Mr. Grieco entered into an Employment
Agreement with National Medical Care, Inc. ("NMC"), a subsidiary of FMC (the
"Employment Agreement"), a copy of which is attached hereto as Exhibit A; and

     WHEREAS, Mr. Grieco, FMC, and FMCAG now desire to enter into an agreement
concerning the separation of Mr. Grieco from FMC.

     NOW, THEREFORE, in consideration of the mutual promises contained in this
Agreement, Mr. Grieco, FMC and FMCAG (the "Parties") agree as follows:

     1.   SEPARATION: The Parties agree that Mr. Grieco shall continue to work
 for and be an employee of the Company through and including July 1, 1999 (the
"Separation Date"), and that until he ceases to be an employee of the Company,
Mr. Grieco shall continue to hold the position of Senior Vice President and
General Counsel. FMC represents and Mr. Grieco agrees that the termination of
Mr. Grieco's employment is not a termination for cause, as set forth in Section
5(a) of the Employment Agreement. Instead, the parties have mutually agreed to
end their current relationship in accordance with Section 5(d) of the Employment
Agreement on the terms and conditions set forth herein.

     2.   CONSIDERATION TO MR. GRIECO: The Company shall make the following
payments and provide the following additional consideration to Mr. Grieco:

          a.   SALARY AND BENEFITS CONTINUATION: Upon the separation of Mr.
Grieco's employment with the Company, the Company agrees to pay Mr. Grieco all
accrued but unpaid base salary through July 1, 1999. In addition, the Company
agrees to the following:

          i.   SALARY. The Company agrees that, beginning on July 2, 1999, Mr.
               Grieco shall receive continuation of his salary, at an annual
               rate of $450,000, from which all applicable withholdings shall be
               made, for a period of two (2) years following the Separation Date
               (the "Salary Continuation"). At Mr. Grieco's option, he may elect
               to receive the


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               Salary Continuation referenced in this Section 2(a)(i) in a lump
               sum (the "Lump Sum Election"), in which event Mr. Grieco shall
               forego the continuation of his life insurance and medical
               benefits provided in Section 2(a)(ii).

         ii.   MEDICAL AND DENTAL COVERAGE, AND LIFE INSURANCE; NO LUMP SUM
               ELECTION. For as long as Mr. Grieco is receiving the Salary
               Continuation, and provided that Mr. Grieco has not made the Lump
               Sum Election, the Company agrees that Mr. Grieco shall receive
               continuation at the Company's expense of any coverage under FMC's
               medical and dental plans, such coverage to be provided to Mr.
               Grieco on the same basis and to the same extent as the coverage
               provided Mr. Grieco during his employment. Mr. Grieco's life
               insurance benefits will similarly continue at the Company's
               expense during the Salary Continuation. Any conversion of life
               insurance at the end of that period (or upon a Lump Sum Election)
               may be arranged through the Corporate Human Resources Department.

         iii.  MEDICAL AND DENTAL COVERAGE, AND LIFE INSURANCE; LUMP SUM
               ELECTION. In the event that Mr. Grieco makes the Lump Sum
               Election as provided in Section 2(a)(i), he shall forego
               continuation of the coverage specified in Section 2(a)(ii); it
               being understood, however, that Mr. Grieco shall have the right
               to elect to pay for coverage himself under COBRA. FMC will send
               Mr. Grieco the documents necessary for such COBRA election.

         iv.   LONG AND SHORT TERM DISABILITY BENEFITS. Mr. Grieco's long and
               short term disability benefits shall cease as of July 1, 1999,
               per company policy.

         v.    401(K) PLAN. Contributions to FMC's 401(k) Plan may be withdrawn
               from the plan by Mr. Grieco following Mr. Grieco's termination of
               employment. Mr. Grieco may not make contributions to the Plan
               during the Salary Continuation period.

         vi.   PENSION PLAN. Mr. Grieco will stop accruing benefit service under
               the Pension Plan effective July 1, 1999.

         vii.  DEFERRED COMPENSATION PLAN. Mr. Grieco's account balance, if any,
               under the Deferred Compensation Plan will be paid to him within
               thirty (30) days of the Separation Date.

         viii. CONTROLLING PLAN DOCUMENTS. It is understood and acknowledged
               that


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               the provision of continued benefits to Mr. Grieco will be
               governed by the terms of the Plan Documents applicable to such
               benefits. The Company will not be under any obligation to amend
               or modify such benefit plans. If Mr. Grieco's benefits cannot be
               continued under the terms of the current group plans, the Company
               will provide equivalent coverage under another plan or plans at
               Company expense.

          ix.  FORM 1099. Mr. Grieco will be provided with a Form 1099 in
               connection with the salary and benefits continuation he receives.

          b.   CONTRACTUAL INCENTIVE COMPENSATION. The parties agree that
incentive compensation provided under the Employment Agreement shall be treated
as follows:

          i.   1999 FMC MANAGEMENT BONUS PLAN. Mr. Grieco will participate in
               the 1999 Management Bonus Plan referenced in Section 4(b) of the
               Employment Agreement, on a pro rata basis for six (6) month's
               service in 1999. Mr. Grieco shall be at the 1999 senior executive
               eligibility level, wherein the target level bonus is forty
               percent (40%) and the maximum bonus is eighty percent (80%) per
               plan of base salary. Mr. Grieco will be treated similarly with
               other senior executives of FMC. Mr. Grieco's entitlement to a
               bonus under the Plan will be governed by the terms of the Plan.
               Payment will be made on the same day as payment to FMC senior
               executives.

          ii.  SPECIAL BONUS. The parties acknowledge that the second paragraph
               of Section 4(b) of the Employment Agreement provides for a
               "Special Bonus." With respect to this Special Bonus the parties
               have agreed that all issues if any, with respect to such bonus
               are reserved and will be decided as per Section 4(b) of the
               Employment Agreement upon the successful resolution of the
               Investigation. By entering into this Agreement now, Mr. Grieco is
               not waiving his right to any possible claim regarding this
               Special Bonus, and is not limiting in any way the amount of the
               bonus he can claim. The Company similarly is not conceding that
               any entitlement to a Special Bonus exists, and is not agreeing
               that a Special Bonus should be awarded at any particular level.
               The parties agree that June 4, 1999 shall be the closing date for
               the evaluation period for the Special Bonus. The parties will
               enter into a tolling agreement with respect to any claims,
               counterclaims and defenses that could be brought in connection
               with the Special Bonus.

          c.   STOCK OPTIONS: Mr. Grieco shall also on the Separation Date
become vested in any Existing Options, consisting of 43,467 Fresenius Medical
Care AG Preference Shares, which are unvested on the Separation Date and in any
Future Options (together with


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any previously vested options, the "Vested Options"). The Company and FMCAG
agree that Mr. Grieco is granted up to three (3) years from the Separation Date
in which to exercise the Vested Options, provided that Ben Lipps, or his
successor, will use his best efforts to recommend to the Management Board of
FMCAG (the "Management Board"), including but not limited to recommending to the
Management Board through an oral and written presentation in accordance with the
normal operating procedures of the Management Board, that Mr. Grieco be granted
up to ten (10) years from the date of the grant of his options to exercise them.
If, despite such aforementioned best efforts, the Management Board in its
reasonable discretion wishes to approve a period less than a ten (10) year
exercise period, Mr. Lipps shall use his "best efforts" to obtain such
alternative approval which would be in one year increments above three years.
If, within three years of July 1, 1999, any other senior executive is granted
more than three years by the Management Board to exercise his or her options,
that same amount of time will be given to Mr. Grieco unless the Management Board
has already granted Mr. Grieco five (5) or more years from the Separation Date
within which to exercise his options, in which case this provision relating to
the exercise period for other executives will become inapplicable, and Mr.
Grieco's exercise period will be that set by the Management Board.

          d.   VACATION/PTO TIME: Mr. Grieco will receive on or before the
Separation Date a payout of all accrued but unpaid vacation/PTO time to which he
is entitled under Company policy, which the Parties agree is 556 hours of time.

          e.   EXPENSE REIMBURSEMENT: The Company acknowledges that Mr. Grieco
has incurred expenses on behalf of the Company which have not yet been
reimbursed, and, in accordance with the Company's policies, the Company will
reimburse Mr. Grieco within ten (10) business days of the submission of
documented proof of such expenses to Brian O'Connell, Vice President of Human
Resources.

          f.   CAR ALLOWANCE: The Company further acknowledges that it has not
yet compensated Mr. Grieco for the automobile allowance provided in Section 4(f)
of the Employment Agreement. The Company agrees to pay Mr. Grieco the amount of
$4,500.00 for such allowance on or before the Separation Date.

          g.   OTHER PAYMENTS: In addition to the foregoing, and as further
consideration for the other terms and conditions set forth in this Agreement,
including a release of all claims to date by Mr. Grieco (with the exception of
the Special Bonus), on or before the tenth day following the execution of this
Agreement by the parties the Company will pay to Mr. Grieco, in a lump sum,
$50,000 from which all applicable withholdings shall be made. On or before
January 1, 2000 the Company will pay to Mr. Grieco, in a lump sum, $50,000 from
which all applicable withholdings shall be made. The Company shall issue to Mr.
Grieco a Form-1099 in connection with these payments.

          h.   CONSULTING AGREEMENT: The Company and Mr. Grieco will enter into
an


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agreement through which Mr. Grieco will agree to provide consulting services to
the Company, at such reasonable times and upon reasonable notice, as the Company
may request as provided below (the "Consulting Agreement"). Mr. Grieco will be
paid a base of $150,000 per year for three years (the "Consulting Fee")
following August 1, 1999 (the "Term") which may increase as set forth under
Section 2(h)(i), unless the consulting arrangement is terminated earlier. The
Consulting Fee shall paid in equal installments on a quarterly basis, in
advance.

        (i.)   The Company acknowledges that Mr. Grieco may assume other
               commitments, and intends to seek other employment and undertake
               other endeavors during the Term. Accordingly, Mr. Grieco's
               consulting obligations shall require not more than 25 hours per
               month (the "Maximum Commitment"). Reasonable travel time above
               and beyond reasonable commuting time (i.e., outside a radius of
               15 miles) shall be counted toward the Maximum Commitment. The
               amount of the Maximum Commitment shall not change during the Term
               of this Agreement, unless the parties mutually agree in writing,
               in which event Mr. Grieco shall be compensated for any increased
               time over the Maximum Commitment at a rate of $500.00 per hour.
               The Company also agrees that if a conflict of interest or
               potential conflict of interest arises in connection with any
               other employment obtained by Mr. Grieco, the Company shall waive
               such conflict or potential conflict as permitted under relevant
               ethical rules governing the practice of law in the Commonwealth
               of Massachusetts.

        (ii.)  The scope of Mr. Grieco's consulting shall be limited to the OIG
               Investigation defense and any related litigation matters, unless
               the parties mutually agree in writing to the contrary.

        (iii.) Mr. Grieco's role shall be that of a legal consultant, with the
               status of outside counsel to the Company.

        (iv.)  Mr. Grieco shall be directed by Dr. Runte or his successor, the
               General Counsel of FMCAG, it being understood that Mr. Grieco
               expects to work with the Company's management team, including
               any new general counsel.

        (v.)   Mr. Grieco's consulting obligations shall begin on August 2,
               1999.

        (vi.)  The Company shall provide Mr. Grieco with reasonable notice and
               a written Request for Assistance, to initiate a consulting
               project. The Company shall provide reasonable lead-time on all
               such projects.


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        (vii.) The Consulting Agreement shall be terminable as follows

                    [a]  BY THE COMPANY FOR GOOD CAUSE. The Company shall have
               the right to terminate the Consulting Agreement for Good Cause
               only. For purposes of the Consulting Agreement, the term "Good
               Cause" shall consist of [1] a material breach of the Consulting
               Agreement or this Agreement by Mr. Grieco,which remains uncured
               for thirty (30) days after receipt by Mr. Grieco of written
               notice from the Company, informing him of its intention to
               terminate under this Section, and providing him with the reasons
               therefore, in detail sufficient to allow cure; or [2]
               Mr. Grieco's failure to provide the consulting services called
               for under the Consulting Agreement for a period of twenty (20) or
               more consecutive days; provided, however, that Mr. Grieco shall
               be entitled to reasonable vacation during the Term and, provided
               further, that if serious illness or other excusable factor beyond
               Mr. Grieco's control prevents him from providing such services,
               the Company shall extend the 20-day period for a reasonable time;
               or [3] Mr. Grieco bringing any action against the Company or any
               of the Releasees as defined in Section 3(a) of any kind in any
               forum, except as provided in Sections 2(b)(ii) and 3(b) or to
               enforce this Agreement.

                    [b]  BY MR. GRIECO FOR GOOD REASON. Mr. Grieco shall have
               the right to terminate the Consulting Agreement for Good Reason.
               For purposes of this Agreement, "Good Reason" shall mean the
               occurrence of any of the following circumstances: (i) a material
               breach of the terms of the Consulting Agreement by FMC or FMCAG,
               which remains uncured for thirty (30) days after receipt by Mr.
               Grieco of written notice from the Company, informing him of its
               intention to terminate under this Section, and providing him with
               the reasons therefore, in detail sufficient to allow cure; (ii) a
               change in Mr. Grieco's reporting line to Dr. Runte or his
               successor; (iii) any interference by FMC or FMCAG in the
               relationship between Mr. Grieco and his employer, which remains
               uncured for thirty (30) days after receipt by the Company of
               written notice from Mr. Grieco, informing it of his intention to
               terminate under this Section, and providing it with the reasons
               therefore, in detail sufficient to allow cure, provided further
               that the Company shall be entitled to only one such notice and
               cure period during each year of the Term; (iv) the Company
               bringing any action against Mr. Grieco of any kind in any forum,
               except as provided in Sections 2(b)(ii) and 3(b) or to enforce
               this Agreement.


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                    [c]  BY MR. GRIECO FOR CONVENIENCE. Mr. Grieco may terminate
               this Agreement for convenience, upon thirty (30) days written
               notice.

                    [d]  EFFECT OF TERMINATION ON COMPANY'S CONSULTING FEE
               OBLIGATION. In the event of a termination properly in accordance
               with Section 2(h)(viii)[a] or Section 2(h)(viii)[c], the Company
               shall pay Mr. Grieco Consulting Fees through the then-current
               quarter, any further obligation to pay to Mr. Grieco Consulting
               Fees shall cease, and no further Consulting Fees shall be due Mr.
               Grieco under the Consulting Agreement. In the event of a
               termination properly in accordance with Section 2(h)(viii)[b],
               the Company's obligations with respect to the Consulting Fees
               shall continue, and all Consulting Fees remaining through the end
               of the Term shall be accelerated, and shall become due and owing
               thirty (30) days after the date of any such termination under
               Section 2(h)(viii)[b].

       (viii.) Mr. Grieco will be reimbursed for the expenses he incurs in
               connection with such consulting, following the submission of
               documentation confirming the expenses in accordance with Company
               policy.

          i.   ENTIRE CONSIDERATION: Mr. Grieco understands and agrees that the
payments and benefits provided for in this Agreement are in excess of those to
which he otherwise would be entitled and that they are being provided to him in
consideration for his signing of this Agreement, which consideration he agrees
is adequate and satisfactory to him. Mr. Grieco understands and agrees that
other than as set forth in this Agreement, he will not receive any compensation,
payment or benefit of any kind from the Company and he expressly acknowledges
and agrees that other than as noted in Sections 2(b)(ii) and 3(b), he is not
entitled to any such further compensation, payment or benefit of any kind,
including any payment with respect to any bonus.

     3.   GRIECO RELEASE: Mr. Grieco, for the consideration given by the Company
as set forth above, which he acknowledges is adequate and satisfactory to him,
hereby commits as follows:

          a.   With the exception of any claims under Sections 2(b)(ii) and
3(b), Mr. Grieco covenants not to sue and irrevocably and unconditionally
remises, releases, waives and forever discharges the Company including its past
and present parents, subsidiaries, affiliates, predecessors, insurers and their
successors and assigns; and its and their past, present and future directors,
officers, agents, representatives and employees, and all persons acting by,
through, under or in concert with them (together the "Releasees"), from any and
all manner of liabilities,


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actions, causes of action, contracts, agreements, promises, claims and demands
of any kind or nature whatsoever, in law or equity, including attorneys' fees,
whether known or unknown, which Mr. Grieco has ever had or now has against the
Company or the Releasees up to and including the Effective Date, including, but
not limited to, claims arising out of or relating to his employment with the
Company and compensation and benefits with the Company, his Employment Agreement
and the separation of his employment from the Company. Mr. Grieco further
agrees, promises and covenants that neither he nor any person, organization, or
other entity acting on his behalf will file, charge, claim, sue or cause or
permit to be filed, charged or claimed, any action for damages or other relief
on his behalf (including injunctive, declaratory, monetary relief or other)
against the Company or any of the Releasees for any liabilities, actions, causes
of action, contracts, agreements, promises, claims and demands of any kind
whatsoever, in law or equity, including attorneys' fees, whether known or
unknown, which he has ever had or now has against the Company or the Releasees
up to and including the Effective Date, including, but not limited to, claims
arising out of or relating to his employment with the Company, compensation and
benefits with the Company, his Employment Agreement and the separation of his
employment from the Company. Mr. Grieco further understands and agrees that this
Agreement and release shall act as a complete bar to any claim, demand or action
of any kind whatsoever which could be brought by and which seeks personal,
equitable or monetary relief for him against the Company or the Releasees up to
and including the Effective Date, including, without limitation, any claim,
demand or action under Title VII of the Civil Rights Act of 1964, 42 U.S.C. ss
2000e, et seq., the Age Discrimination in Employment Act, 29 U.S.C. ss 621,
et seq., the Employee Retirement Income Security Act of 1974, chapters 93A and
151B of the Massachusetts General Laws; all claims of defamation or damage to
reputation; all claims for reinstatement; all claims for punitive or emotional
distress damages; all claims for wages, benefits, bonuses, expenses, severance,
back or front pay or other forms of compensation; all claims for stock or stock
options; and all claims for attorney's fees and costs, and any and all other
federal, state or local statutes, or common laws, except for claims for a breach
of this Agreement and with respect to any benefits in which Mr. Grieco has a
vested interest under the terms and conditions of any of the Company's employee
benefit plans. Mr. Grieco hereby waives and relinquishes any and all rights he
may have under any federal, state or local statute, rule, regulation or
principle of common law or equity which may in any way limit the effect of this
release with respect to claims which he did not know or suspect to exist in his
favor at the time he executed this Agreement.

          b.   The released claims in Section 3(a) shall not, however, include
any claims to enforce any obligations under this Agreement, and it is further
understood and agreed by the parties that Mr. Grieco is not waiving and hereby
expressly reserves the right to seek payment of the "Special Bonus" discussed in
the second paragraph of Section 4(b) of the Employment Agreement (on p. 2), upon
and under the terms and conditions set forth in Section 4(b) of the Employment
Agreement. The parties hereby agree that all issues, if any, with respect to the
Special Bonus are reserved.

          c.   Mr. Grieco agrees that other than in an action brought by him
under Section


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2(b)(ii) and 3(b), neither he nor any person, organization or entity acting on
his behalf will file, participate, join in, encourage, assist, facilitate or
permit the bringing or maintenance of any claim or cause of action against the
Company or the Releasees relating to Mr. Grieco's employment or other matters
arising during his employment with the Company for which he had responsibility,
unless his participation as a witness is called for by a prosecutorial agency or
is required by subpoena or other legal process of which he shall give reasonable
notice to the Company, provided that this paragraph shall not be violated by his
participation in any class action or action brought by the government provided
that he opt out at the first possible opportunity. This Section 3(c) shall not
apply in any situation which conflicts with his ethical obligations under the
rules governing the practice of attorneys in Massachusetts or his interest as an
individual witness or defendant in any investigations or claims which give rise
to such interests.

          d.   Mr. Grieco agrees that other than as set forth herein, he is not
entitled to any future employment with the Company or any of the Releasees,
whether as an employee, consultant or otherwise, except as set forth in this
Agreement, and that he will not in the future seek any employment with the
Company or any of the Releasees, whether as an employee consultant or otherwise,
except as set forth in this Agreement and the Consultant Agreement.

     4.   FMC AND FMCAG RELEASE: The Company and FMCAG, and their affiliates,
predecessors, successors, assigns, officers, directors, representatives and
attorneys hereby irrevocably and unconditionally release, acquit and forever
discharge Mr. Grieco and his successors, assigns, agents, representatives and
attorneys, and all persons acting by, through, under or in concert with him
(collectively "Employer's Releasees"), and any of them, from any and all
charges, complaints, claims, liabilities, obligations, promises, agreements,
controversies, damages, actions, causes of action, suits, rights, demands,
costs, losses, debts and expenses (including attorneys' fees and costs actually
incurred), of any nature whatsoever, known or unknown (collectively "Employer's
Released Claims"), which the Company and/or FMCAG now has, owns, or holds, or
claims to have, own, or hold, or which the Company and/or FMCAG at any time had,
owned, or held, or claimed to have, own, or hold against each of any of the
Employer's Releasees from the beginning of time until the Effective Date of this
Agreement. The Employer's Released Claims shall include, without express or
implied limitation, all claims of breach of express or implied contract; all
claims under Massachusetts General Laws chapter 93A; all claims of interference
with contractual or advantageous relations, whether prospective or existing; all
claims of deceit or misrepresentation; all claims of defamation or damage to
reputation; all claims for punitive damages; and all claims for attorney's fees
and costs. The Employer's Released Claims shall not include any claims to
enforce any obligation under this Agreement, and it is further understood and
agreed by the parties that the Company and FMCAG are not waiving and hereby
expressly reserve the right to assert any and all claims and defenses it may
have with respect to the Special Bonus in any proceeding brought by Mr. Grieco.

     5.   NON-DISPARAGEMENT: Each of the Parties agrees that it shall not issue
any communication, written, verbal or otherwise, that disparages any other party
including with respect


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to Mr. Grieco's job performance or his employment as Senior Vice President and
General Counsel of FMC or which encourage any adverse action, provided that the
parties shall testify truthfully under oath pursuant to a subpoena and/or Court
order or other valid legal process. There will be no liquidated damages for any
breach of this clause and Ben Lipps will not have any personal liability under
this Section 5 unless Massachusetts law permits the imposition of personal
liability and a breach is proven in a court of law to have been engaged in by
Mr. Lipps himself.

     6.   INDEMNIFICATION: The Company and FMCAG agree to indemnify Mr. Grieco
and hold him harmless from any and all claims against Mr. Grieco arising out of
his employment with NMC or with the Company, arising out of his position as
Senior Vice President, arising out of his position as member of the Board of the
Company, arising out of his position as officer, director, or shareholder of any
affiliate of the Company or FMCAG, arising out of his Consulting Agreement, or
arising out of any combination or all of the above. The Company agrees that Mr.
Grieco shall be entitled to retain counsel, consultants, and expert witnesses in
connection with the defense of, or his involvement in, any such claims, and
agrees to indemnify Mr. Grieco for any resulting reasonable attorney's fees,
reasonable consultants' fees, and reasonable expert witness fees. The Company
represents and warrants that, at all times during Mr. Grieco's employment, Mr.
Grieco has been covered by the Company's Directors' and Officers' Insurance
which is and has been good and sufficient in light of known or anticipated
claims. The Company further represents and warrants that such coverage for Mr.
Grieco will remain in place, for the period during which Mr. Grieco might remain
exposed to such claims.

     7.   COOPERATION AND ASSISTANCE: Mr. Grieco acknowledges that he may have
historical information or knowledge which may be useful to the Company in
connection with current or future legal, regulatory or administrative
proceedings. Mr. Grieco will cooperate with the Company in the defense or
prosecution of any such claims which relate to events or occurrences that
transpired during Mr. Grieco's employment with the Company. Mr. Grieco's
cooperation in connection with such claims or actions shall include being
reasonably available to meet with counsel to prepare for discovery or trial and
to testify truthfully as a witness when reasonably requested by the Company at
reasonable times and with reasonable advance notice to Mr. Grieco. The Company
shall promptly reimburse Mr. Grieco for any out-of-pocket expenses, including
Mr. Grieco's personal attorney's fees, that he incurs in connection with such
cooperation. The Company shall also provide Mr. Grieco with compensation on an
hourly basis at the rate of three hundred fifty dollars ($350.00) per hour for
such requested cooperation, including preparation time. The Company agrees that
time spent by Mr. Grieco in fulfilling his obligations under this Section 7
shall not involve the OIG Investigation defense or any related litigation
matters, which services are governed exclusively by Section 2(h) of this
Agreement. Mr. Grieco shall not be obligated to provide such cooperation which
conflicts with his ethical obligations under the rules governing the practice of
attorneys in Massachusetts.

     8.   NOTICE OF PUBLIC INFORMATION RELEASE: For a period of two (2) years
commencing on the Effective Date, the Company and FMCAG agree that at least two
(2) days before dissemination


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it will provide Mr. Grieco with a copy of any information to be released by the
Company and FMCAG publicly that references Mr. Grieco, his employment, or Mr.
Grieco's involvement in the Investigation, including, but not limited to, any
SEC filing, Investor Communication, or press statement (collectively
"Mr. Grieco-Related Statements"). Any inaction by Mr. Grieco shall not affect
the Company's obligations under Section 5.

     9.   OUTPLACEMENT BENEFITS: For a period of one year following the
Separation Date the Company will provide Mr. Grieco with
executive/professional-level out-placement at a firm to be agreed upon by the
parties, with the Company's consent to the selection of a firm by Mr. Grieco not
to be unreasonably withheld.

     10.  LETTER OF REFERENCE: Within fourteen (14) days of the Separation Date,
the Company will provide Mr. Grieco with a mutually acceptable, written, letter
of reference.

     11.  UNEMPLOYMENT BENEFITS: The Company agrees that it will not protest any
claim Mr. Grieco may file for unemployment compensation.

     12.  PAYMENTS TO ESTATE: Should Mr. Grieco die, any payments remaining
unpaid under this Agreement at the time of his death, shall be paid to his
estate.

     13.  RETURN OF PROPERTY: Mr. Grieco expressly agrees that by the Separation
Date he will return to the Company all property of the Company including, but
not limited to, any and all files, computers, computer equipment and software
and diskettes, documents, papers, records, accords, notes, agenda, memoranda,
plans, calendars and other books and records of any kind and nature whatsoever
containing information concerning the Company or its customers or operations.
Mr. Grieco affirms that he has not retained and will not retain copies of any
such property or other materials. It is agreed that as the only exception to
this Section 13, Mr. Grieco may retain one copy of his own attorney work product
and any other documents covered under Massachusetts Rules of Professional
Conduct Rule 1.16, and at the request of the Company Mr. Grieco has agreed to
and will provide a list of all such documents to the Company within a reasonable
period of time of the Separation Date. Mr. Grieco agrees that he will not
disclose such retained documents to any other individual or entity without the
written permission of the Company, except as permitted under the ethical rules
governing the practice of law in the Commonwealth of Massachusetts. At Mr.
Grieco's request, the Company shall provide, at its own expense, secretarial,
paralegal and other assistance to Mr. Grieco to prepare the list.

     14.  NON-DISCLOSURE: Mr. Grieco agrees that he has not, except in
performing his duties, and will not at any time hereafter directly or indirectly
publish, disclose, market or use, or authorize, advise, hire, counsel or
otherwise procure any other person or entity, directly or indirectly, to
publish, disclose, market or use, any trade secret or other information of a
confidential or proprietary nature of the Company ("Trade Secrets"), whether
patentable or nor, of which he became aware or informed during this employment
with the Company. Mr. Grieco may,


                                      -11-
<PAGE>   12


however, comply with legal process, provided he (i) gives the Company prompt
notice of the date any disclosure must be made to enable the Company to respond
to any such process, and (ii) waits until the last possible date to make any
such disclosure.

     14.  NON-DISCLOSURE: Mr. Grieco acknowledges and affirms that he continues
to be bound and will abide by, and following the Separation Date will continue
to be bound and abide by, the nondisclosure provisions contained in Paragraph 6
of the Employment Agreement.

     15.  NO ADMISSION: Nothing in this Agreement shall be deemed to constitute
an admission or evidence of any wrongdoing or liability on the part of the
Company or Mr. Grieco and the parties agree that neither this Agreement nor any
of the terms or conditions contained herein other than as set forth in Section
16, may be used in any future dispute or proceeding except one to enforce the
terms of this Agreement, and except if the parties agree in writing.

     16.  CONFIDENTIALITY: Mr. Grieco agrees that he will keep confidential the
terms of this Agreement, and agrees that he will not disclose its terms to
anyone other than members of his immediate family, counsel and tax advisors who
must also each agree prior to such disclosure to them to keep the terms of this
Agreement confidential, or as required by law, or as permitted by the ethical
rules governing the practice of law in the Commonwealth of Massachusetts, or as
requested by a government taxing authority. The Company shall also treat this
Agreement as confidential and shall not disclose it to persons other than those
required for its approval and proper implementation within the Company, and to
its counsel and tax advisors or as required by law or regulation or to
government taxing authorities, provided that it is agreed that as the only
exceptions to this Section 16, Mr. Grieco and the Company may disclose (i) that
Mr. Grieco has separated from the Company, (ii) that this was a mutually
agreeable separation, (iii) that Mr. Grieco has been retained as a consultant,
(iv) that Mr. Grieco's rate as a consultant is $500.00 per hour and (v) that all
issues regarding Mr. Grieco's Special Bonus have been reserved.

     17.  BINDING NATURE OF AGREEMENT: This Agreement shall be binding upon each
of the Parties and upon their heirs, administrators, representatives, executors,
successors and assigns, and shall inure to the benefit of each party and to
their heirs, administrators, representatives, executors, successors and assigns.

     18.  NO ORAL MODIFICATION: This Agreement may not be changed orally and no
modification, amendment or waiver of any provision contained in this Agreement,
or any future representation, promise or condition in connection with the
subject matter of this Agreement shall be binding upon any party hereto unless
made in writing and signed by such party.

     19.  ENTIRE AGREEMENT: Pursuant to Section 2(h) of this Agreement, the
parties contemplate executing a Consulting Agreement incorporating the terms set
forth in Section 2(h). This Agreement will incorporate that Consulting Agreement
upon execution of that Consulting Agreement, and will then contain the entire
agreement between the parties and supersede any and


                                      -12-
<PAGE>   13


all previous agreements of any kind whatsoever between them, whether written or
oral. All prior and contemporaneous discussions and negotiations have been and
will then be merged and integrated into, and be superseded by, this Agreement.
This is an integrated document.

     20.  SEVERABILITY: In the event that any provision of this Agreement or the
application thereof should be held to be void, voidable, unlawful or, for any
reason, unenforceable, the remaining portion and application shall remain in
full force and effect, and to that end the provisions of this Agreement are
declared to be severable.

     21.  GOVERNING LAW: This Agreement is made and entered into, and shall be
subject to, governed by, and interpreted in accordance with the laws of the
Commonwealth of Massachusetts and shall be fully enforceable in the courts of
that state, without regard to principles of conflict of laws. The Parties
(i) agree that any suit, action or other legal proceeding arising out of this
Agreement may be brought in the United States District Court for the District of
Massachusetts, or if such court does not have jurisdiction or will not accept
jurisdiction, in any court of general jurisdiction in Suffolk County,
Massachusetts; (ii) consent to the jurisdiction of any such court; and
(iii) waive any objection which they may have to the laying of venue in any such
court. The parties also consent to the service of process, pleadings, notices or
other papers by regular mail, addressed to the party to be served, postage
prepaid, and registered or certified with return receipt requested.

     22.  NOTICES: All notices, requests, consents, approvals and other
communications required or permitted under this Agreement ("Notices") shall be
in writing and shall be delivered to the addresses listed below, by mail, by
hand, or by facsimile transmission, unless otherwise provided in this Agreement.
Such Notices shall be effective (i) if sent by mail, three business days after
mailing; (ii) if sent by hand, on the date of delivery; and (iii) if sent by
facsimile, on the date indicated on the facsimile confirmation. A copy of any
Notice sent by facsimile shall also be sent by express air mail or overnight
mail on the date such Notice is transmitted by facsimile.

     In the case of Mr. Grieco:

          William F. Grieco
          115 Marlborough Street, Unit 1
          Boston, Massachusetts  02116
          Phone:  617-353-0536
          Fax:  617-353-0536

     with a copy to:

          Ieuan G. Mahony, Esq.
          Holland & Knight LLP
          One Beacon Street


                                      -13-
<PAGE>   14


          Boston, MA  02018
          Phone:  617-523-2700
          Fax:  617-523-6850

     In the case of Fresenius Medical Care Holdings, Inc. and Fresenius Medical
Care AG:

          Fresenius Medical Care Holdings, Inc. and
            Fresenius Medical Care AG
          c/o Fresenius Medical Care Holdings, Inc.
          95 Hayden Avenue
          Lexington, Massachusetts  02420
          Attention:  Brian O'Connell, Vice President Human Resources
          Phone:  781-402-9205
          Fax:  781-402-9734

     and

          Fresenius Medical Care AG
          Else-Kroner-Strasse
          61352 Bad Homburg v.d.H.
          Germany
          Attention: Dr. Rainer Runte

     with a copy to:

          Christopher A. Parlo, Esq.
          Morgan, Lewis & Bockius LLP
          101 Park Avenue
          New York, New York  10178
          Phone:  212-309-6000
          Fax:  212-309-6273

     Any party may change its address or facsimile number for notification
purposes by giving the other parties notice, in accordance with the notice
provisions set forth in this Section, of the new address or facsimile number and
the date upon which it will become effective.

     23.  NO ASSIGNMENT: Neither this Agreement nor any portion hereof is
assignable. The Parties represent, warrant and covenant that they have not
previously assigned or transferred, or purported to assign or transfer, to any
individual or entity, any of the rights being released herein, and agree that no
such assignment or transfer may occur without a written consent executed by both
parties, and any attempt to do so shall be void.

     24.  COUNTERPARTS: This Agreement may be executed in counterparts, and each


                                      -14-
<PAGE>   15


counterpart, when executed, shall have the effect of a signed original.

     25.  ACKNOWLEDGMENT OF KNOWING AND VOLUNTARY RELEASE: Mr. Grieco certifies
that he has read the terms of this Agreement. The execution hereof by Mr. Grieco
shall indicate that this Agreement conforms to Mr. Grieco's understandings and
is acceptable to him as a final agreement. It is further understood and agreed
that Mr. Grieco has been advised of the opportunity to consult with counsel of
his choice and that he has been given a reasonable and sufficient period of time
of no less than 21 days in which to consider and return this document. It is
further agreed and understood that upon Mr. Grieco's execution and return of
this document he is thereafter permitted to revoke the Agreement at any time
during a period of seven (7) days following his execution hereof. This agreement
shall not be effective until the seven day revocation period has expired. To be
effective, the revocation must be in writing and must be hand-delivered or
telecopied to counsel for the Company within the seven-day period.

     WHEREFORE, intending to be legally bound, the parties have agreed to the
aforesaid terms and indicate their agreement by signing below.

[PLEASE READ CAREFULLY. THIS AGREEMENT IS A LEGAL DOCUMENT AND INCLUDES A
RELEASE OF ALL KNOWN AND UNKNOWN CLAIMS, INCLUDING, WITHOUT LIMITING THE
GENERALITY OF THE FOREGOING, ALL CLAIMS ARISING UNDER TITLE VII OF THE CIVIL
RIGHTS ACT OF 1964, AS AMENDED, THE AGE DISCRIMINATION IN EMPLOYMENT ACT, AS
AMENDED, THE EMPLOYEE RETIREMENT INCOME SECURITY ACT, AS AMENDED, AND CHAPTERS
93A AND 151B OF THE MASSACHUSETTS GENERAL LAWS.

BY SIGNING THIS AGREEMENT I ACKNOWLEDGE AND AFFIRM THAT I AM COMPETENT, THAT I
HAVE BEEN AFFORDED A TIME PERIOD OF 21 DAYS TO REVIEW AND CONSIDER THIS
AGREEMENT AND HAVE BEEN ADVISED TO DO SO WITH AN ATTORNEY OF MY CHOICE. THAT I
HAVE READ AND UNDERSTAND AND ACCEPT THIS DOCUMENT AS FULLY AND FINALLY WAIVING
AND RELEASING ANY AND ALL CLAIMS, DEMANDS, DISPUTES AND ANY DIFFERENCES OF ANY
KIND WHATSOEVER WHICH I MAY HAVE HAD OR NOW HAVE AGAINST THE COMPANY ARISING OUT
OF OR RELATING TO MY EMPLOYMENT WITH THE COMPANY, COMPENSATION AND BENEFITS WITH
THE COMPANY, SEPARATION FROM EMPLOYMENT OR OTHERWISE, EXCEPT AS PROVIDED HEREIN,
THAT NO REPRESENTATIONS, PROMISES OR INDUCEMENTS HAVE BEEN MADE TO ME EXCEPT AS
SET FORTH IN THIS AGREEMENT, AND THAT I HAVE SIGNED THIS DOCUMENT FREELY AND
VOLUNTARILY, INTENDING TO BE LEGALLY BOUND BY ITS TERMS, AND WITH FULL
UNDERSTANDING OF ITS CONSEQUENCES.

     WILLIAM F. GRIECO


                                      -15-
<PAGE>   16


     /s/ William F. Grieco                                    __________________
     ---------------------
     William F. Grieco                                        Date



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



     By:   /s/ Ben Lipps                                       _________________
           -------------
           Ben Lipps, Chief Executive Officer                  Date



     FRESENIUS MEDICAL CARE AG



     By:   /s/ Ben Lipps                                        ________________
           -------------
           Ben Lipps, Chairman and                              Date
           Chief Executive Officer


     By    /s/ Dr. Rainer Runte                                 ________________
           --------------------
           ppa. Dr. Rainer Runte                                Date
           General Counsel
           Senior Vice President


                                      -16-