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                                                                EXHIBIT 10.05(b)
                                                                ----------------
                              AMENDMENT NO. 1 TO

                         REGISTRATION RIGHTS AGREEMENT

           THIS AMENDMENT NO. 1 TO REGISTRATION RIGHTS AGREEMENT (the
"Amendment") is made and entered into as of the 6th day of November, 1996, by
and between OCCUPATIONAL HEALTH + REHABILITATION INC, a Delaware corporation
(the "Company") and Argosy Health, L.P., a Pennsylvania limited partnership (the
"Holder"), pursuant to the terms of that certain Registration Rights Agreement
dated as of September 11, 1996 (the "Original Agreement") by and between the
Company and the Holder. All capitalized terms not defined herein shall have the
meanings ascribed to them in the Original Agreement.

                                  WITNESSETH

           WHEREAS, the Company and the Holder entered into the Original
Agreement; and

           WHEREAS, simultaneously with the execution of this Amendment, in
connection with and as a condition to the Company's sale of its Series A
Convertible Preferred Stock, the Company will enter into that certain
Registration Rights Agreement dated as of the date hereof (the "Investor Rights
Agreement") with certain investors of the Company listed on Schedule A thereto;
and

           WHEREAS, the Investor Rights Agreement includes certain provisions
relating to underwriter cutbacks which are inconsistent with the Original
Agreement and provides certain additional rights to holders with Rule 144
rights; and

           WHEREAS, the Holder holds at least two-thirds of the aggregate number
of outstanding shares of Restricted Stock held by the Holders or their permitted
successors and assigns; and

           WHEREAS, the Company and the Holder desire to amend the Original
Agreement pursuant to Section 10(d) thereof in order to improve the consistency
among the registration rights granted by the Company;

           NOW THEREFORE, the Original Agreement is hereby amended as follows,
effective as of the date and year first above written:
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1.        The last sentence of Section 4 of the Original Agreement entitled
"Incidental Registration" is hereby deleted in its entirety and the following
substituted in lieu thereof:

           In the event that any registration pursuant to this Section 4 shall
           be, in whole or in part, an underwritten public offering of Common
           Stock, the number of shares of Restricted Stock to be included in
           such an underwriting may be reduced if and to the extent that the
           managing underwriter shall be of the opinion that such inclusion
           would adversely affect the marketing of the securities to be sold by
           the Company or the requesting party therein or that such reduction is
           otherwise advisable, provided, however, that after any shares to be
           sold by selling holders that do not have contractual rights to have
           shares included in such registration have been excluded, shares to be
           sold by the Holders shall be excluded in such manner that the shares
           to be excluded shall first be the shares of selling Holders and other
           requesting holders who, in each case, are not affiliates (as defined
           in Rule 144 of the Securities Act) of the Company (the "Affiliate
           Holders") and whose shares are then saleable under Rule 144(e) or
           Rule 144(k) under the Securities Act and then pro rata among them,
           and if further reduction is necessary, shall next be pro rata among
           the remaining shares of the selling Holders and other requesting
           holders who are Affiliate Holders or whose shares are not then
           saleable under Rule 144(e) or Rule 144(k), unless such registration
           is pursuant to the exercise of a demand right of another security
           holder, in which event such security holder shall be entitled to
           include all shares it desires to have so included before any shares
           of Restricted Stock or shares of any other holder are included
           therein and provided, however, that notwithstanding anything in this
           Agreement to the contrary, in respect of the first underwritten
           public offering following the date of the Investor Rights Agreement,
           no reduction shall reduce the number of shares which may be sold by
           requesting holders who are parties to the Investor Rights Agreement
           to less than 25% of the shares to be sold in such offering.

2.         The last paragraph of Section 9 of the Original Agreement is hereby
deleted in its entirety and the following substituted in lieu thereof:

                     The Company shall not be required to effect a registration
           pursuant to Section 4 hereof for any Holder desiring to participate
           in such registration who (a) may then dispose of all of its shares of
           Restricted Stock pursuant to Rule 144 within the three-month period
           following such proposed registration; and (b) holds less than 1% of
           the outstanding capital stock of the Company (on a common
           stock-equivalent basis) at the time of such registration.

3.         The term "Agreement" as used in the Original Agreement shall mean the
Original Agreement, as amended by this Amendment.

4.         As so amended by this Amendment, the Original Agreement shall remain
in full force and effect.

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           IN WITNESS WHEREOF, each party hereto has caused this Amendment to be
signed in counterpart or otherwise by its duly authorized officer or partner, as
the case may be, as of the date and year first written above.

                                 COMPANY:
                                 
                                 OCCUPATIONAL HEALTH +
                                   REHABILITATION INC
                                 
                                 By:
                                    -----------------------------------
                                     John C. Garbarino
                                     Its President and Chief Executive Officer
                                 
                                 HOLDER:
                                 
                                 ARGOSY HEALTH, L.P.
                                 
                                 By: Gwynedd Partners, Inc.
                                 
                                     By:
                                        --------------------------------
                                        Name:
                                             ---------------------------
                                        Title:  Its President

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