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                                                                    Exhibit 8.1

                     [MORRIS, MANNING & MARTIN LETTERHEAD]


                                 July 7, 2000



InfoCure Corporation
1765 The Exchange
Suite 500
Atlanta, GA 30339


Ladies and Gentlemen:

         We have acted as counsel to InfoCure Corporation ("InfoCure"), a
Delaware corporation, in connection with the proposed merger (the "Merger") of
CADI Acquisition Corporation ("Merger Sub"), a Colorado corporation and a
direct wholly-owned transitory merger subsidiary of InfoCure, with and into
Medical Dynamics, Inc. ("Medy"), a Colorado corporation, pursuant to an
Agreement and Plan of Merger and Reorganization dated as of December 21, 1999,
as amended by that certain First Amendment to Agreement and Plan of Merger by
and among Medy, InfoCure and Merger Sub dated April 10, 2000, and that certain
Second Amendment to Agreement and Plan of Merger by and among Medy, InfoCure
and Merger Sub dated June 22, 2000 (the "Merger Agreement"). The Merger is
described in the Registration Statement of InfoCure on Form S-4 (the
"Registration Statement") filed on the date hereof with the Securities and
Exchange Commission (the "Commission") under the Securities Act of 1933, as
amended (the "Securities Act"), which includes the joint proxy statement and
prospectus of Medical Dynamics and InfoCure (the "Proxy Statement/Prospectus").

         In that connection, we have reviewed the Merger Agreement, the Proxy
Statement/Prospectus and such other materials as we have deemed necessary or
appropriate for purposes of our opinion. In addition, we have assumed (i) that
the Merger will be consummated in accordance with the provisions of the Merger
Agreement and as contemplated by the Proxy Statement/Prospectus and (ii) the
truth and accuracy, on the date of the Merger Agreement and on the date hereof,
of the representations and warranties made by InfoCure, Medy and Merger Sub in
the Merger Agreement.

         Based upon and subject to the foregoing, in our opinion, the
discussion contained in the Registration Statement under the caption "Material
Federal Income Tax Consequences of the Merger," subject to the limitations and
qualifications described therein, sets forth the material United States federal
income tax considerations generally applicable to the Merger. Because this

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MORRIS, MANNING & MARTIN
A LIMITED LIABILITY PARTNERSHIP


July 7, 2000
Page 2

opinion is being delivered prior to the effective time of the Merger, it must
be considered prospective and dependent upon future events. There can be no
assurance that changes in the law will not take place which could affect the
federal income tax consequences of the Merger or that contrary positions may
not be asserted by the Internal Revenue Service.

         This opinion is being furnished in connection with the Registration
Statement. You may rely upon and refer to the foregoing opinion in the Proxy
Statement/Prospectus. Any variation or difference in any fact from those set
forth or assumed either herein or in the Proxy Statement/Prospectus may affect
the conclusions stated herein.

         We hereby consent to the use of our name under the caption "Material
Federal Income Tax Consequences of the Merger" in the Proxy
Statement/Prospectus and to the filing of this opinion as an Exhibit 8.1 to the
Registration Statement. In giving this consent, we do not admit that we come
within the category of persons whose consent is required under Section 7 of the
Securities Act or the rules and regulations of the Commission thereunder.

                                       Very truly yours,

                                       MORRIS, MANNING & MARTIN, LLP



                                       By:/s/ Charles R. Beaudrot, Jr., Partner
                                          -------------------------------------
                                          Charles R. Beaudrot, Jr., Partner