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                                                                  Exhibit 10.13

                              EXTENSION SUPPLEMENT

         EXTENSION  SUPPLEMENT,  dated as of May 31,  1999 (this  "Supplement"),
between   Northstar   Health  Services,   Inc.,  a  Delaware   corporation  (the
"Borrower"),  Cerberus Partners, LP and Bear, Stearns & Co. Inc.  (collectively,
the "Lenders").

                                   WITNESSETH

         WHEREAS,  IBJ  Schroder  Bank & Trust  Company  (the  "Agent")  and the
Borrower are parties to that certain Forbearance  Agreement,  dated as of August
18, 1997 (as  amended,  supplemented  or  otherwise  modified  prior to the date
hereof, the "Forbearance Agreement"); and

         WHEREAS, the Forbearance  Agreement shall by its terms terminate on May
31, 1999 (the "Old Forbearance Termination Date");

         WHEREAS,   the  Borrower  has  requested   that  the  Old   Forbearance
Termination  Date be extended as  contemplated  by Section 4 of the  Forbearance
Agreement,  and the Agent and the Lenders are willing to agree to such extension
but only on the terms and subject to the conditions set forth herein;

         NOW, THEREFORE, in consideration of the premises and for other valuable
consideration,  the receipt and adequacy of which are hereby  acknowledged,  the
Borrower and the Agent hereby agree as follows:

         1. Definitions. Terms defined in or by the reference in the Forbearance
Agreement are used herein as therein defined.

         2. Forbearance  Termination  Date. The Forbearance  Termination Date is
hereby extended to July 31, 1999 (the "New Forbearance Termination Date").


         3.  Effectiveness.  This  Supplement  shall become  effective  upon the
receipt  by the  Lenders  of  evidence  satisfactory  to the  Lenders  that this
Supplement has been executed and delivered by the Borrower.

         4. Representations and Warranties.  To induce the Lenders to enter into
this  Supplement,  the Borrower hereby  represents and warrants to the Agent and
the Lenders  that,  after  giving  effect to the  extension  of the  Forbearance
Termination  Date  and the  other  modifications  to the  Forbearance  Agreement
provided  for  herein,  the  representations  and  warranties  contained  in the
Forbearance  Agreement  will be true and correct in all material  respects as if
made on and as of the date hereof and that no Forbearance  Event of Default will
have occurred and be continuing.


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         5. No Other  Modifications.  Except as expressly  modified hereby,  the
Forbearance  Agreement  shall remain in full force and effect in accordance with
its terms,  without  any  waiver,  amendment  or  modifcation  of any  provision
thereof.

         6. No Waiver.  The parties  hereto agree that the Agent and the Lenders
have not waived or  consented  to any  Default or Event of  Default,  waived any
right or  remedy  they may have with  respect  to any such  Default  or Event of
Default,  or  agreed  to any  modification  or  waiver  of any of the  terms and
provisions of the Loan Documents.

         7. Counterparts.  This Supplement may be executed by one or more of the
parties  hereto  on  any  number  of  separate  counterparts  and  all  of  said
counterparts  taken  together  shall be  deemed to  constitute  one and the same
instrument.

         8. Applicable Law. THIS SUPPLEMENT  SHALL BE GOVERNED BY, AND CONSTRUED
AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

         9. Payment of Principal. In addition to the monthly interest payable by
the Borrower to the  Lenders,  on (a) June 1, 1999,  the  Borrower  shall pay an
aggregate of $100,000 to the Lenders which  payment shall  represent the monthly
principal  installment due on June 1, 1999 under the latest draft of the Amended
and Restated  Loan  Agreement  and (b) July 1, 1999,  the Borrower  shall pay an
aggregate of $100,000 to the Lenders which  payment shall  represent the monthly
principal  installment due on July 1, 1999 under the latest draft of the Amended
and Restated Loan  Agreement.  In the event that the Borrower shall fail to make
any such payment,  the Lenders  reserve the right to immediately  terminate this
forbearance extension prior to the New Forbearance Termination Date.

         10.  Interest Rate. The parties hereby agree that effective as of April
1, 1999,  the Interest  Rate on the Loans shall be  calculated as the sum of (a)
the higher of (x) the Prime Rate (as defined in the Loan  Documents) and (y) the
Federal Funds Rate plus 0.5%, plus (b) 2.125%.

                            [SIGNATURE PAGE FOLLOWS]


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                  IN WITNESS  WHERE OF, the  parties  hereto  have  caused  this
         Supplement  to be duly  executed  and  delivered as of the day and year
         first above written.


                                      NORTHSTAR HEALTH SERVICES, INC.



                                      By /s/ Thomas W. Zaucha
                                         ------------------------------
                                         Name: Thomas W. Zaucha
                                         Title: President & CEO


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                                      CERBERUS PARTNERS, L.P.



                                      By
                                         ------------------------------
                                         Name:  Joyce Johnson-Miller
                                         Title:  Managing Director



                                      BEAR, STERNS & CO. INC.



                                      By
                                         ------------------------------
                                         Name: Gregory A. Hanley
                                         Title: Senior Managing Director



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                                      IBJ SCHRODER BANK & TRUST COMPANY



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



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