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                                    EXHIBIT A

     JOINT FILING AGREEMENT AMONG IRIDIAN ASSET MANAGEMENT LLC, LC CAPITAL
     MANAGEMENT, LLC, CL INVESTORS, INC., DAVID L. COHEN AND HAROLD J. LEVY


     AGREEMENT,  between Iridian Asset  Management LLC  ("Iridian"),  LC Capital
Management, LLC ("LC"), CL Investors, Inc. ("CLI"), David L. Cohen ("Cohen") and
Harold J. Levy ("Levy").

     WHEREAS, in accordance with Rule 13d-1(f) under the Securities Exchange Act
of 1934 (the "Act"), only one statement  containing the information  required by
Schedule  13G and any  amendments  thereto  need be filed  whenever  two or more
persons are  required to file such a statement  or any  amendments  thereto with
respect to the same securities, provided that said persons agree in writing that
such statement or any amendment thereto is filed on behalf of them.

     NOW,  THEREFORE,  in  consideration  of the premises and mutual  agreements
contained herein, the parties hereto agree as follows:

     Iridian,  LC, CLI, Cohen and Levy, do hereby agree, in accordance with Rule
13d-1(f)  under the Act, to file a Schedule 13G  relating to their  ownership of
the common stock of  Allegiance  Corporation,  and do hereby  further agree that
said Schedule 13G shall be filed on behalf of each of them.


Date: February 8, 1999

                                   IRIDIAN ASSET MANAGEMENT LLC

                         By:           /s/ Jeffrey M. Elliott
                                   ----------------------------------
                                   Jeffrey M. Elliott, Executive Vice President


                                   LC CAPITAL MANAGEMENT, LLC

                         By:           /s/ Jeffrey M. Elliott
                                   ----------------------------------
                                   Jeffrey M. Elliott, Executive Vice President


                                   CL INVESTORS, INC.

                         By:           /s/ Jeffrey M. Elliott
                                   ----------------------------------
                                   Jeffrey M. Elliott, President


                         By:           /s/ David L. Cohen
                                   ----------------------------------
                                   David L. Cohen, individually


                         By:           /s/ Harold J. Levy
                                   ----------------------------------
                                   Harold J. Levy, individually

