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                                                                   EXHIBIT 10.21


                Amendment to the Agreement and Plan of Merger,
                        dated as of September 29, 2000
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                               AMENDMENT TO THE
                               ----------------
AGREEMENT AND PLAN OF MERGER BY AND AMONG, HALIS, INC., HEALTHWATCH MERGER SUB,
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                          INC. AND HEALTHWATCH, INC.
                          --------------------------

     This AMENDMENT TO THE AGREEMENT AND PLAN OF MERGER BY AND AMONG, HALIS,
INC., HEALTHWATCH MERGER SUB, INC. AND HEALTHWATCH, INC. ("Amendment"), dated as
of September 29, 2000 is made and entered into by and among (i) Halis, Inc.
("Halis"), a Georgia corporation, (ii) HealthWatch Merger Sub, Inc.("Merger
Sub"), a Georgia Corporation and (iii) HealthWatch, Inc. ("HealthWatch"), a
Minnesota corporation.

     WHEREAS, Halis, Merger Sub and HealthWatch have entered into that certain
Agreement and Plan of Merger dated as of June 29, 2000 (the "Agreement") in
which HealthWatch will acquire Halis upon the merger of Halis with and into
Merger Sub, a wholly-owned subsidiary of HealthWatch, upon the terms and
conditions included in the Agreement; and

     WHEREAS, the parties desire to extend the date provided in Section 7.1(b)
and Section 5.1(d) of the Agreement to allow the additional time required to
satisfy the conditions to closing the merger.

     THEREFORE, for good and valuable consideration, the receipt and sufficiency
of which hereby are acknowledged, the parties, intending to be legally bound, do
hereby agree as follows:

     1.   Section 7.1(b) of the Agreement shall be deleted in its entirety and
replaced with the following:

     "(b) by either the Board of Directors of Halis or the Board of Directors of
     HealthWatch: (i) if the Merger shall not have been consummated by January
     31, 2001, unless such termination right has been expressly restricted in
     writing by the Board of Directors of Halis or HealthWatch, as the case may
     be; provided, however, that the right to terminate this Agreement pursuant
     to this Section 7.1(b)(i) shall not be available to any party whose failure
     to perform any of its obligations under this Agreement results in the
     failure of the Merger to be consummated by such time; (ii) if the
     HealthWatch Stockholder Approval shall not have been obtained at a
     HealthWatch Stockholders' Meeting duly convened therefor or at any
     adjournment or postponement thereof; (iii) if the Halis Stockholder
     Approval shall not have been obtained at a Halis Stockholders' Meeting duly
     convened therefor or at any adjournment or postponement thereof; (iv) if
     any Restraint having any of the effects set forth in Section 6.1(d) shall
     be in effect and shall have become final and nonappealable, or if any
     Governmental Entity that must grant a Requisite Regulatory Approval has
     denied approval of the Merger and such denial has become final and
     nonappealable; provided, that the party seeking to terminate this Agreement
     pursuant to this Section 7.1(b)(iv) shall have used commercially reasonable
     efforts to prevent the entry of and to remove such Restraint or to obtain
     such Requisite Regulatory Approval, as the case may be; or (v) if the
     financial advisor opinion required by Section 6.1(g) or (h) is not received
     because the advisor indicates that it does not deem the transaction fair as
     stated in such Sections."

     2.   Section 5.1(d) of the Agreement shall be deleted in its entirety and
replaced with the following:
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     "(d) Halis and HealthWatch will use commercially reasonable efforts to hold
the HealthWatch Stockholders' Meeting and the Halis Stockholders' Meeting on the
same date and as soon as reasonably practicable after the date hereof, but not
later than January 31, 2001."

     3.   Except as modified by this Amendment, all terms and conditions of the
Agreement are hereby reaffirmed.

     IN WITNESS WHEREOF, the undersigned have executed this Amendment as of the
effective date mentioned above.

                                        HALIS, INC.

                                        By: /s/ Joel Greenspan
                                        Its: Member of the Board of Directors

                                        Attest: /s/ Marilyn May
                                        Its: Secretary

                                             [CORPORATE SEAL]

                                        HEALTHWATCH, INC.

                                        By: /s/ Thomas C. Ridenour
                                        Its: Chief Financial Officer

                                        Attest: /s/ Marilyn May
                                        Its: Secretary

                                             [CORPORATE SEAL]

                                        HEALTHWATCH MERGER SUB, INC.

                                        By: /s/ Paul W. Harrison
                                        Its: President

                                        Attest: /s/ Marilyn May
                                        Its: Secretary

                                             [CORPORATE SEAL]

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