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                                                                     EXHIBIT 8.1





                             ARMSTRONG TEASDALE LLP
                             One Metropolitan Square
                                   Suite 2600
                            St. Louis, MO 63102-2740


                                                  August 24, 2000


Kupper Parker Communications, Inc.
8301 Maryland Avenue
St. Louis, MO  63105

         Re:      Greenstone Roberts Advertising, Inc.
                  Registration Statement on Form S-4

Ladies and Gentlemen:

         You have requested our opinion with respect to certain federal income
tax consequences of the proposed merger and reorganization (the "Merger")
pursuant to the Agreement and Plan of Merger dated as of August 23, 2000 (the
"Agreement"), between KPCI, a Missouri corporation ("KPCI") and Greenstone
Roberts Advertising, Inc., a New York corporation("GRAI"). Specifically, you
have requested our opinion as to whether, for federal income tax purposes, the
Merger qualifies as a reorganization within the meaning of Section 368(a) of the
Internal Revenue Code of 1986, as amended, and all regulations promulgated
thereunder (the "Code"), by reason of Section 368(a)(1)(A) of the Code, to which
each of KPCI and GRAI will be a party to the reorganization within the meaning
of Section 368(a) of the Code. For purposes of this opinion, all capitalized
terms, unless otherwise specified, have the meanings assigned to them in the
Agreement.

         In rendering our opinion, we have examined and relied on the accuracy
and completeness of the facts, information, statements and representations
contained in the Agreement and in the Registration Statement on Form S-4, filed
on the date hereof (the "Registration Statement") filed with the Securities and
Exchange Commission under the Securities Act of 1933 relating to
5,073,950 shares of GRAI common stock. In connection with this opinion, we have
also relied upon statements and representations made to us in certificates by
GRAI and KPCI with respect to certain factual matters (the "Certificates"),
which statements and representations we have neither investigated nor verified.
The opinions expressed herein are conditioned on the initial and continuing
accuracy of the facts, information, statements and representations set forth in
the Certificates and filings referred to above. We have assumed that all such
facts, information, statements and representations qualified by the knowledge
and belief of GRAI or KPCI will be complete and accurate as of the Effective
Time as though not so qualified. We have further assumed that the Merger will be
performed in accordance with the terms of the Agreement and the description of
the transaction in the Registration Statement.

         In rendering our opinion, we have considered the applicable provisions
of the Code, the Treasury Regulations promulgated thereunder, pertinent judicial
authorities and published rulings and other pronouncements of the Internal
Revenue Service, all as of the date hereof. Any change in the foregoing may
affect the continuing validity of the opinion set forth herein. We express no
opinion as to the tax consequences of the Merger under any laws other than the
federal income tax laws of the United States.


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         In our opinion, the statements in the prospectus/proxy statement (the
"Proxy Statement") contained in the Registration Statement under the caption
"The Merger-Material Federal Income Tax Consequences", to the extent they
constitute matters of law or legal conclusions, are accurate in all material
respects.

         The foregoing opinion is based solely on and subject to (a) the
qualifications, assumptions and limitations set forth herein, and (b) the
qualifications, limitations and assumptions contained in the portion of the
Proxy Statement captioned "The Merger-Material Federal Income Tax Consequences".

         We hereby consent to the use of our name under the caption "Legal
Matters" in the Proxy Statement and to the filing of this opinion with the
Securities and Exchange Commission as an exhibit to the Registration Statement.
In giving such consent, we do not admit that we are within the category of
persons whose consent is required under Section 7 of the Securities Act of 1933,
as amended.


                                             Very truly yours,

                                             ARMSTRONG TEASDALE LLP




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