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                                                                   EXHIBIT 10.10


                                                                January 18, 2000


Gentiva Health Services, Inc.
175 Broad Hollow Road
Melville, New York  11747


Attention:  Edward A. Blechschmidt


     Re: GENTIVA -- CONVERTIBLE TRUST PREFERRED SECURITIES COMMITMENT LETTER


Ladies and Gentlemen:

         Gentiva Health Services, Inc., a Delaware corporation ("GENTIVA" or
"YOU"), has advised the party set forth on the signature pages hereto as a
purchaser (the "PURCHASER") that Olsten Corporation, a Delaware corporation and
Gentiva's parent ("OLSTEN"), has agreed, pursuant to an Agreement and Plan of
Merger by and among Adecco SA ("ADECCO"), Staffing Acquisition Corporation
("SAC") and Olsten dated as of August 17, 1999, as amended (the "Merger
Agreement"), to (i) merge Olsten with and into SAC, and (ii) split off all of
the outstanding common stock of Gentiva to Olsten's stockholders (the
"SPLIT-OFF" and, together with the Merger, the "TRANSACTION").

         You have requested that the Purchaser commit to purchase 10%
Convertible Trust Preferred Securities, liquidation preference $1,000 per share
to be issued by a wholly-owned trust of Gentiva (the "CONVERTIBLE TRUST
PREFERRED SECURITIES"), in an aggregate liquidation preference set forth below
the Purchaser's signature.

         Accordingly, subject to the terms and conditions set forth below, the
Purchaser agrees with you as follows:

         1. COMMITMENT. For good and valuable consideration, the receipt of
which the Purchaser hereby acknowledges, the Purchaser hereby commits to
purchase the aggregate liquidation preference of the Convertible Trust Preferred
Securities set forth beneath the signature of the Purchaser contemporaneously
with the consummation of the Transaction, upon the terms and subject to the
conditions set forth or referred to herein and in the Summary of Terms and
Conditions attached hereto (and incorporated by reference herein) as EXHIBIT A
(the "TERM SHEET").

         2. CONDITIONS. The Purchaser's commitment hereunder is subject to (a)
the negotiation, execution and delivery of the definitive documentation
evidencing the issuance and sale of the Convertible Trust Preferred Securities,
(b) consummation of the Transaction, and (c) receipt by Gentiva of any consents
required to be received to permit the issuance and sale of the Convertible Trust
Preferred Securities, which consents shall be in full force and effect at the
time of the issuance and sale.


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         3. EXPENSES. Each party shall bear its own respective expenses in
connection with the issuance and sale of the Convertible Trust Preferred
Securities.

         4. CONFIDENTIALITY. This Commitment Letter, the Term Sheet, the
contents of any of the foregoing and the Purchaser's and Gentiva's activities
pursuant hereto are confidential and shall not be disclosed by the Purchaser to
any person without Gentiva's prior written consent, other than to the
Purchaser's advisors, and then only in connection with the Transaction and on a
confidential and need-to-know basis, except as required by applicable law or
compulsory legal process.

         5. TERMINATION. In the event that (i) the Transaction is not
consummated by May 31, 2000; (ii) Olsten or Adecco terminates the Merger
Agreement; or (iii) Olsten or Adecco shall publicly announce its intention to
abandon the Transaction, this Commitment Letter and the Purchaser's commitment
hereunder shall terminate (upon written notice by the Purchaser with respect to
clause (i) of this sentence and automatically without any further action with
respect to clauses (ii) or (iii) of this section). Notwithstanding the foregoing
sentence, the provisions of Section 7 hereof shall survive any such termination.

         6. ASSIGNMENT, ETC. This Commitment Letter and our commitment hereunder
shall not be assignable by any of the parties hereto without the prior written
consent of the other parties hereto, and any attempted assignment shall be void
and of no effect. This Commitment Letter is solely for the benefit of the
parties hereto and does not confer any benefits upon, or create any rights in
favor of, any other person.

         7. GOVERNING LAW; WAIVER OF JURY TRIAL. This Commitment Letter shall be
governed by, and construed in accordance with, the laws of the State of New
York. Each of the parties hereto waives all right to trial by jury in any
action, proceeding or counterclaim (whether based upon contract, tort or
otherwise) related to or arising out of any of the Transaction or the other
transactions contemplated hereby, or the performance by us of the obligations
contemplated hereby.

         8. AMENDMENTS; COUNTERPARTS, ETC. No amendment or waiver of any
provision hereof or the Term Sheet shall in any event be effective unless in
writing and signed by the parties hereto and then only in the specific instance
and for the specific purpose for which given. This Commitment Letter and the
Term Sheet are the only agreements among the parties hereto with respect to the
issuance and sale of the Convertible Trust Preferred Securities and set forth
the entire understanding of the parties with respect thereto. This Commitment
Letter may be executed in any number of counterparts and by different parties
hereto in separate counterparts, each of which when so executed shall be deemed
to be an original and all of which taken together shall constitute one and the
same agreement. Delivery of an executed counterpart hereof by telecopier shall
be effective as delivery of a manually executed counterpart hereof.

         9. NOTICES. Any notice given pursuant hereto shall be mailed or
hand-delivered in writing, if to (i) you, at your address set forth on page one
hereof, with a copy to Kenneth W. Orce at Cahill Gordon & Reindel, 80 Pine
Street, New York, New York 10005 and (ii) the Purchaser, at the address set
forth on such Purchaser's signature page.


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                            [Signature Pages Follow]


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         Please confirm that the foregoing correctly sets forth our agreement of
the terms hereof by signing and returning to the undersigned the duplicate copy
of this letter. Upon your acceptance hereof, this letter shall constitute a
binding agreement between you and us.

                                   Very truly yours,

                                                            , as Purchaser


                                   By:
                                        -----------------------------------
                                        Name:
                                        Title:
                                        Address:


                                        Amount of Convertible Trust Preferred
                                        Securities to be purchased:   $


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Accepted and agreed to as of
the date first written above:

GENTIVA HEALTH SERVICES, INC.


By:
    -------------------------
       Name:
       Title:
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<CAPTION>


    GENTIVA HEALTH SERVICES -- TERMS FOR A CONVERTIBLE TRUST PREFERRED OFFERING

<S>                                              <C>
ISSUER:                                           A trust to be formed by Gentiva Health Services (the "Company")

AMOUNT:                                           Not less than $20.0 million

MATURITY:                                         2005 (5 years)

ISSUE PRICE:                                      100%

COUPON:                                           10.0%

DISTRIBUTIONS:                                    Holders of the preferred securities are entitled to receive cumulative cash
                                                  distributions at an annual rate of 10% accruing from the date of original
                                                  issuance and payable quarterly in arrears.

CONVERSION PREMIUM:                               17.5% based on the average closing stock price for Gentiva for the ten trading
                                                  days after the first earnings announcement after the closing of the transaction
                                                  (in order to insure clarity of information).

RANK:                                             The convertible subordinated debentures to be issued to the trust by the Company
                                                  will be subordinate and junior in right of payment to all senior indebtedness of
                                                  the Company. The preferred securities will rank PARI PASSU with the most senior
                                                  preferred stock now or hereafter issued by the trust.

OPTION TO EXTEND INTEREST PAYMENT                 The Company has the right at any time , so long as no indenture event of default
                                                  has occurred or is continuing, to defer payment of interest on the convertible
                                                  subordinated debenture by extending the interest payment period on the convertible
                                                  subordinated debentures, on one or more occasions, for up to 20 consecutive
                                                  quarters. During any deferral, distributions will continue to accrue with interest
                                                  thereon. The trust has the same right to defer interest on the preferred
                                                  securities.
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                                     -7-

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<S>                                              <C>
REDEMPTION:                                       The convertible subordinated debentures are redeemable by the Company (and the
                                                  preferred securities are redeemable by the trust) in whole or in part at the
                                                  redemption prices specified below.

                                                  2000 -- 110%
                                                  2001 -- 108%
                                                  2002 -- 106%
                                                  2003 -- 104%
                                                  2004 -- 102%
                                                  2005 -- 100%

VOTING RIGHTS:                                    None

CHANGE OF CONTROL:                                Upon the occurrence of a change of control, the trust will be required to
                                                  repurchase all or any part of each holder's preferred securities at a price equal
                                                  to 100% of par for each security plus accumulated and unpaid distributions.

TAX FEATURE:                                      Coupon payments on the preferred stock and interest payments on the convertible
                                                  subordinated debentures are tax deductible for the trust and Gentiva respectively.
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