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                                                                   Exhibit 10.20


                             EMPLOYMENT AGREEMENT
                             --------------------



Parties:  HOME HEALTH CORPORATION OF AMERICA, INC.
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          a Pennsylvania corporation ("Employer")
          2200 Renaissance Boulevard, Suite 300
          King of Prussia, PA  19406

          DAVID S. GELLER ("Executive")
          868 Westminster Drive
          Lancaster, Pennsylvania 17601

Date:     July 20, 1998
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Background: Employer desires to employ Executive and Executive desires to be
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employed by the Employer as the Chief Financial Officer of Employer.  In
consideration of Executive's future services to Employer, Employer desires to
provide for the payment of certain compensation and other benefits to Executive,
all as more fully described in this Agreement.

     INTENDING TO BE LEGALLY BOUND, and in consideration of the mutual covenants
and agreements stated below, Executive and Employer agree as follows:

     1.   Employment and Term:  Employer hereby employs Executive and Executive
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accepts such employment, subject to all of the terms and conditions of this
Agreement, for a term of three (3) years beginning on July 20, 1998 (the
"Term"). The Term will automatically be extended for an additional one (1) year
period on July 19th of each year, unless sooner terminated in accordance with
other provisions of this Agreement or prior to such date either party gives the
other party written notice of its intention not to extend this Agreement, all in
accordance with the terms of this Agreement.

     2.   Position and Duties.  Employer shall employ Executive as its Chief
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Financial Officer. Executive shall report directly to the Employer's President
and Chief Executive Officer. Executive shall have the normal duties,
responsibilities and authority of the Chief Financial Officer and shall
undertake such responsibilities and duties that may be assigned to him from time
to time by the Employer's President and Chief Executive Officer. Executive shall
devote all of his working time, energy, skill and best efforts to Employer's
business and affairs and to the promotion of Employer's interests as is required
for the fulfillment of his obligations and the performance of his duties under
this Agreement, except that Executive shall not be precluded from pursuing
personal business interests, so long as such activities do not materially
interfere with Executive's performance of his duties under this Agreement.
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     3.   Compensation, Benefits and Expenses.
          ----------------------------------- 

          3.1  Salary.  Employer shall pay to Executive a gross base salary of
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One Hundred Sixty Five Thousand Dollars ($165,000.00) ("Base Salary"); provided,
                                                                       -------- 
however, that commencing on January 20, 1999, Executive's Base Salary shall be
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One Hundred Seventy Five Thousand Dollars ($175,000.00). The Base Salary shall
be reviewed each January 20 thereafter by the Employer's President and Chief
Executive Officer and may be increased (but not decreased) based upon
Executive's performance. Executive's Base Salary shall be payable in accordance
with Employer's normal payroll practices for employees and Employer shall deduct
or cause to be deducted from Executive's Base Salary all taxes and amounts
required by law to be withheld.

          3.2  Benefits.  Employer shall pay to Executive an automobile expense
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allowance of Four Hundred Fifty Dollars ($450.00) per month. To the extent he is
eligible under the general provisions thereof, Executive shall be entitled to
participate in and shall be included in all other employee benefit plans, group
insurance, disability, profit sharing, savings, bonus, health insurance, life
insurance, retirement, stock or similar plans or programs of Employer.

          3.3  Bonuses.  In addition to his Base Salary, Executive shall be
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eligible to participate in the Company's Executive Management Bonus Program
(the "Bonus") in the event that Employer and its subsidiaries achieve targeted
consolidated net income (the "Targeted Income"). Subject to approval, in its
sole discretion, of Employer's Compensation Committee, it is anticipated that
the Bonus available to Executive shall be up to twenty-five percent (25%) of
Executive's Base Salary in the event that Employer and its subsidiaries achieve
Targeted Income, to be determined after the issuance of the audited financial
statements of Employer and its subsidiaries; provided, however, that Employer's
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Compensation Committee, in its sole discretion, may amend the Bonus Program at
any time.

          3.4  Vacation.  Executive shall be entitled to four weeks of vacation
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during each year.

          3.5  Expenses.  Executive is authorized to incur, and shall be
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promptly reimbursed by Employer for, ordinary, necessary and reasonable expenses
in the course of his performance of services under this Agreement.  Executive
shall properly account for all such expenses.

          3.6   Entire Compensation.  The compensation provided for in this
                -------------------                                        
Section 3, together with the grant of stock options to the Executive pursuant to
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the Employer's Amended and Restated 1995 Employee and Consultant Equity Plan,
shall be the full consideration for the services to be rendered by Executive to
Employer under this Agreement.

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<PAGE>
 
     4.   Termination.
          ----------- 

          4.1  Termination by Death.  If Executive dies, then this Agreement and
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all of Executive's rights to compensation and benefits under this Agreement
shall terminate immediately, except that Executive's heirs, personal
representatives or estate shall be entitled to receive the unpaid portion of
Executive's Base Salary and any accrued benefits up to the date of death,
including a pro rata share of Executive's Bonus, if any, for such fiscal year,
and to any benefits that are to be continued or paid after the date of
termination in accordance with the terms of the corresponding benefit plans.

          4.2  Termination by Disability.  If Executive becomes disabled, he
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shall continue to receive all of his compensation and benefits in accordance
with Section 3 for a period of 12 months following the Onset of Disability (as
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defined in this Section 4.2).  If Executive's disability continues for more than
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12 months after the Onset of Disability or for periods aggregating more than 12
months during any 24 month period, then Employer shall have the right to
terminate this Agreement and all of Executive's rights to compensation and
benefits under this Agreement immediately, except that Executive shall be
entitled to receive the unpaid portion of Executive's Base Salary, any accrued
benefits up to the date of Employer's termination pursuant to this Section 4.2
                                                                   -----------
and any benefits that are to be continued or paid after the date of termination
in accordance with the terms of the corresponding benefit plans. Any amounts due
to Executive under this Section 4.2 shall be reduced, dollar-for-dollar, by any
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amounts received by Executive under any disability insurance policy or plan
provided to Executive by Employer. "Onset of Disability" means the first day on
which Executive shall be unable to perform his duties under this Agreement by
reason of physical or mental incapacity, sickness or infirmity.

          4.3  Termination for Cause.  Employer may, upon thirty (30) days prior
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written notice, terminate Executive's employment and his rights to compensation
and benefits under this Agreement for Cause (as defined in this Section 4.3),
                                                                -----------  
except that Executive shall be entitled to receive any unpaid portion of
Executive's Base Salary and benefits earned to the date of termination and any
benefits that are to be continued or paid after the date of termination for
Cause in accordance with the terms of the corresponding benefit plans. "Cause"
shall exist if Executive is convicted of a felony, is grossly negligent in the
performance of his duties under this Agreement, commits a material act of
dishonesty or breach of trust with respect to Employer or materially breaches
this Agreement, but only if Executive is given notice specifying, in reasonable
detail, the nature of the alleged cause and Executive had a reasonable
opportunity to take remedial action but failed or refused to do so.

          4.4  Termination for Good Reason.  Executive may, upon thirty (30)
               ---------------------------                                  
days prior written notice (except with respect to subsection 4.4(e) for which
ninety (90) days prior written 

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<PAGE>
 
notice shall be required) to Employer, resign his employment for "Good Reason".
Good Reason shall exist if:

               (a) Executive is demoted, removed or not re-elected to any of his
positions or offices, or there is a material diminishment of Executive's
responsibilities, duties or status;

               (b) there is a reduction in Executive's Base Salary or a material
reduction in Executive's benefits;

               (c) Employer breaches a material provision of this Agreement;

               (d) a "Change in Control" occurs, which for purposes of this
Agreement, shall mean a change in control of Employer of a nature that would be
required to reported in response to Item 6(e) of Schedule 14A of Regulation 14A
promulgated under the Securities Exchange Act of 1934, as amended (the "Exchange
Act"), whether or not Employer is then subject to such reporting requirement;
provided that, without limitation, such a change in control shall be deemed to
have occurred if:

                   (i) any person (as such term is used in Section 13(d) and
14(d)(2) of the Exchange Act), other than those persons in control of Employer
as of the date hereof, shall acquire the power, directly or indirectly, to
direct the management or policies of Employer or shall become the beneficial
owner (within the meaning of Rule 13d-3 under the Exchange Act), directly or
indirectly, of 50% or more of the combined voting power of Employers' then
outstanding securities; or

                   (ii) during any period of two (2) consecutive years,
individuals who at the commencement of such period constitute the entire Board
of Directors of Employer shall cease for any reason to constitute at least a
majority thereof unless the election, or the nomination for election by
Employer's shareholders, of each new director was approved by a vote of at least
two-thirds of the directors then still in office who were directors at the
commencement of such period; provided, however, that for purposes of this
subsection, all directors elected in accordance with the foregoing procedure
shall be deemed to be directors at the commencement of such period;

In the event of a Change in Control, all of the stock options and awards issued
to Executive under any stock option plan of Employer (collectively, the
"Options") shall become fully vested as of the date of such Change in Control,
regardless of the terms of any such stock option plan.

               (e) Employer relocates its principal executive offices without
Executive's consent to a location more than fifty (50) miles from the principal
offices of Employer in King of Prussia, Pennsylvania;

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               (f) any failure by Employer to obtain the assumption of this
Agreement by any successor or assign of Employer; or

               (g) any purported termination of Executive for Cause that is not
effected pursuant to the method described in Section 4.3.
                                             ----------- 

          4.5  Termination Without Cause.  Employer may, upon thirty (30) days
               -------------------------                                      
prior written notice to Executive, terminate his employment without Cause.

          4.6  Termination By Executive.  Executive may, upon ninety (90) days
               ------------------------                                       
prior written notice to Employer, terminate his employment with Employer.

          4.7  Benefits Upon Termination by Executive for Good Reason,
               -------------------------------------------------------
Termination by Employer Without Cause or Termination upon Employer Notice.  In
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the event that (i) Executive chooses to resign from his employment hereunder for
Good Reason pursuant to Section 4.4, (ii) Employer terminates Executive's
                        -----------                                      
employment without Cause pursuant to Section 4.5 or (iii) Employer elects not to
                                     -----------                                
extend this Agreement pursuant to Section 1, then: (1) Executive shall continue
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to receive for a period of twelve (12) months after such termination (the
"Severance Period"), his Base Salary payable in regular installments as if he
was still employed by Employer (the "Severance Payments");  provided, however,
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that in the event Executive chooses to resign from his employment for Good
Reason pursuant to Section 4.4, the Severance Period shall be the greater of:
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(a) twelve (12) months after such termination; or (b) the number of months
remaining in the initial Term; (2) all of the Options shall be fully vested as
of the date his employment terminates, regardless of the terms of the stock
option plan of Employer pursuant to which such Options were issued; and (3)
health insurance of Executive shall continue to be provided by Employer for a
period of twelve (12) months from the date of his termination.

          4.8  Procedure upon Termination.  Upon termination of his employment,
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Executive shall promptly return to Employer all documents (including copies) and
other materials and property of Employer, or pertaining to its businesses,
including without limitation customer and prospect lists, contracts, files,
manuals, letters, reports and records in his possession or control, no matter
from whom or in what manner acquired.

     5.   Discoveries.  Executive shall communicate to Employer, in writing when
          -----------                                                           
requested, and preserve as confidential information of Employer, all marketing
concepts and each discovery, idea, design, invention and improvement relating in
any manner to Employer's business that has been conceived, developed or made by
Executive, whether alone or jointly with others, at any time (during or after
business hours) during Executive's employment with Employer (such concepts,
ideas and designs are referred to as "Executive's Discoveries").  All of
Executive's Discoveries shall be 

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<PAGE>
 
Employer's exclusive property, and Executive shall, at Employer's expense, sign
all documents and take such other actions as it may reasonably request to
confirm its ownership of Executive's Discoveries. Executive shall not, except
with Employer's express prior written consent, or except in the proper course of
his employment with Employer, use any of Executive's Discoveries for his own
benefit or the benefit of any person or disclose any of Executive's Discoveries
to any third person through publication or in any other manner.

     6.   Nondisclosure.  At all times during and after the Term, except with
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Employer's express prior written consent or in connection with the proper
performance of services under this Agreement, Executive shall not, directly or
indirectly, communicate, disclose or divulge to any person or use for the
benefit of any person, any confidential or proprietary knowledge or information,
no matter when or how acquired, concerning the conduct and details of the
business of Employer including, but not limited to, (a) names of customers,
prospects and suppliers, (b) details of customer, prospect and supplier
contracts and proposals, (c) budget and other non-public financial information
and (d) marketing methods, trade secrets and financial condition. For purposes
of this Section 6, confidential information shall not include any information
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that is now known by the general public,  that becomes known by the general
public other than as a result of any improper act or omission of Executive, or
that Executive is required to disclose pursuant to a judicial process; provided,
                                                                       -------- 
however, that Executive shall notify Employer of such judicial process, and give
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Employer the opportunity to contest such disclosure.

     7.   Noncompetition.  Executive acknowledges that Employer's business is
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highly competitive, and that the services Employer provides are complex and
sophisticated and require substantial and continuous expenditures of time and
money to develop, market and maintain. Accordingly, during the Non-Compete
Period (as hereinafter defined), except with Employer's express prior written
consent, Executive shall not, directly or indirectly, in any capacity, for the
benefit of any person:

          (a)  communicate with or solicit any person who is or during such
period becomes an executive employee or salesperson of Employer in any manner
that interferes or might interfere with such person's relationship with Employer
or in an effort to obtain such person as an employee of any person;

          (b)  communicate with or solicit any person who is or during such
period becomes a customer, supplier, agent or representative of Employer in any
manner that interferes or might interfere with such person's relationship with
Employer, or in an effort to obtain such person as a customer, supplier, agent
or representative of any person that conducts a business in competition with
Employer; and/or

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<PAGE>
 
          (c)  establish, own, manage, operate or control, or participate in the
establishment, ownership, management, operation or control of, serve as an
employee, director, officer or consultant for, or make a material investment in,
any person that conducts a home health care business (including, without
limitation, the provision of private duty or Medicare-reimbursable nursing and
related health care services and equipment to home-bound patients (including
without limitation bedside care and treatment, infusion therapy, pharmaceutical
and rehabilitative services), and the provision of mobile diagnostic services)
in competition with Employer within a 100-mile radius of any of Employer's
offices; provided, however, that this provision shall not be construed to
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prohibit the ownership by Executive of not more than two percent (2%) of any
class of securities of any corporation engaged in such a home health care
business that has a class of securities registered pursuant to the Exchange Act.

For purposes of this Agreement, the Non-Compete Period shall mean the period
during which Executive is employed by Employer and continuing for a period of
time equal to the greater of (i)  one (1) year after termination of Executive's
employment hereunder or (ii) the Severance Period; provided, however, that in
                                                   --------  -------         
the event that Executive terminates his employment for Good Reason pursuant to
Section 4.4., or Executive is terminated without Cause pursuant to Section 4.5,
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the Non-Compete Period shall continue for a period of time equal to the
Severance Period.  Notwithstanding the foregoing, in the event that Employer
shall fail to provide Executive with the compensation owed to Executive pursuant
to Section 4.6, the Non-Compete Period shall automatically terminate and
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Executive shall from that day forward not be subject to the restrictions set
forth in this Section 7.
              --------- 

     8.   Remedy.  Executive acknowledges that the covenants contained in
          ------                                                         
Sections 5, 6 and 7 of this Agreement ("Covenants") are a material part of the
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consideration bargained for by Employer and that, without the agreement of
Executive to be bound by the Covenants, Employer would not have agreed to enter
into this Agreement. Executive acknowledges that any breach by him of any of the
Covenants will result in irreparable injury to Employer for which money damages
could not adequately compensate Employer. If there is such a breach, Employer
shall be entitled, in addition to all other rights and remedies which Employer
may have at law or in equity, to have an injunction issued by any competent
court enjoining and restraining Executive and all other persons and entities
involved therein from continuing such breach. The existence of any claim or
cause of action which Executive or any such other person or entity may have
against Employer shall not constitute a defense or bar to the enforcement of any
of such Covenants. If Employer must resort to legal proceedings to enforce any
Covenant that has a fixed term, then such term shall be extended for a period of
time equal to the period during which a breach of such Covenant was occurring,
beginning on the date of a final order of a court or other tribunal (without
further right of appeal) holding that such a breach occurred or, if later, the
last day of the original fixed term of such Covenant. If any portion of any such
Covenant or its application is construed to be invalid, illegal or
unenforceable, then the other portions and their application shall not be
affected thereby and shall be enforceable without regard thereto. If any of the
Covenants is determined to be unenforceable because of its 

                                      -7-
<PAGE>
 
scope, duration, geographical area or similar factor, then the court or tribunal
making such determination shall have the power to reduce or limit such scope,
duration, area or other factor, and such Covenant shall then be enforceable in
its reduced or limited form.

     9.   Indemnification.  Executive shall be indemnified by Employer, to the
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maximum extent permitted under applicable law and the articles of incorporation
and bylaws of Employer, for all acts of Executive as an officer of Employer
and/or any other company that Executive serves as an officer at the request of
Employer.

     10.  Prior Agreements.  Executive represents to Employer (a) that there are
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no restrictions, agreements or undertakings whatsoever to which Executive is a
party which would prevent or make unlawful his execution of this Agreement or
his employment hereunder, (b) that his execution of this Agreement or his
employment hereunder do not constitute a breach of any contract, agreement or
understanding, oral or written, to which he is a party or which he is bound and
(c) that he is free and able to execute this Agreement and to enter into
employment by Employer.

     11.  Mitigation.  Executive shall not be required to mitigate the amount of
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any payment provided for in Sections 3 or 4 hereof by seeking employment or
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otherwise. Employer shall not be entitled to setoff against the amounts payable
to Executive hereunder any amounts earned by Executive in other employment after
termination of his employment with Employer hereunder or any amounts that might
have been earned by Executive in other employment had he sought such other
employment. The amounts payable to Executive hereunder shall not be treated as
damages but as severance compensation to which Executive is entitled by reason
of termination of his employment in the circumstances contemplated by this
Agreement.

     12.  Notices.  All notices, consents or other communications required or
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permitted to be given under this Agreement shall be in writing and shall be
deemed to have been duly given (a) when delivered personally, (b) three business
days after being mailed by first class certified mail, return receipt requested,
postage prepaid, or (c) one business day after being sent by a reputable
overnight delivery service, postage or delivery charges prepaid, to the parties
at their respective addresses stated on the first page of this Agreement.
Notices may also be given by prepaid telegram or telecopy and shall be effective
on the date transmitted if confirmed within 24 hours thereafter by a signed
original sent in the manner provided in the preceding sentence. Any party may
change its address for notice and the address to which copies must be sent by
giving notice of the new addresses to the other parties in accordance with this
Section 12, except that any such change of address notice shall not be effective
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unless and until received.

     13.  Entire Agreement.  This Agreement is the entire agreement between the
          ----------------                                                     
parties with respect to the subject matter hereof and may not be terminated,
modified or amended except in a writing executed by each party hereto affected
by such termination, modification or amendment. 

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<PAGE>
 
This Agreement supersedes all prior agreements and understandings among the
parties with respect to its subject matter.

     14.  Assignment.  This Agreement, being for the personal services of
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Executive, shall not be assignable by him.

     15.  No Waivers.  No waiver with respect to this Agreement shall be
          ----------                                                    
enforceable unless in writing and signed by the party against whom enforcement
is sought. Except as otherwise expressly provided herein, no failure to
exercise, delay in exercising, or single or partial exercise of any right, power
or remedy by any party, and no course of dealing between or among any of the
parties, shall constitute a waiver of, or shall preclude any other or further
exercise of the same or any other right, power or remedy.

     16.  Severability.  If any provision of this Agreement is construed to be
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invalid, illegal or unenforceable, then the remaining provisions hereof shall
not be affected thereby and shall be enforceable without regard thereto.

     17.  Counterparts.  This Agreement may be executed in any number of
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counterparts, each of which when so executed and delivered shall constitute an
original hereof, and it shall not be necessary in making proof of this Agreement
to produce or account for more than one original counterpart hereof.

     18.  Controlling Law.  This Agreement is made under, and shall be construed
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and enforced in accordance with, the laws of the Commonwealth of Pennsylvania
applicable to agreements made and to be performed solely therein, without giving
effect to principles of conflicts of law.

     WITNESS THE DUE EXECUTION AND DELIVERY HEREOF on the date first above
written.


EMPLOYER:                                       EXECUTIVE:

HOME HEALTH CORPORATION
OF AMERICA, INC.


By: /s/ Bruce J. Feldman                        /s/ David S. Geller
   ---------------------                        -------------------
   BRUCE J. FELDMAN                             DAVID S. GELLER
   President and Chief Executive Officer

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