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                                                                    EXHIBIT 8.01


                            SMITH, ANDERSON, BLOUNT,
                      DORSETT, MITCHELL & JERNIGAN, L.L.P.


           OFFICES                                           MAILING ADDRESS
2500 FIRST UNION CAPITOL CENTER                               P.O. BOX 2611
 RALEIGH, NORTH CAROLINA 27601                           RALEIGH, NORTH CAROLINA
                                                                27602-2611

                                                       TELEPHONE: (919) 821-1220
                                                       FACSIMILE: (919) 821-6800
                                                              


                              ______________, 1999


Quintiles Transnational Corp.
4709 Creekstone Drive
Riverbirch Building, Suite 200
Durham, North Carolina 27703

        Amended and Restated Agreement and Plan of Merger Dated as of December
        15, 1998 By and Among Quintiles Transnational Corp., QELS Corp. and
        Envoy Corporation

Gentlemen:

         We have acted as counsel to Quintiles Transnational Corp.
("Quintiles"), a North Carolina corporation, in connection with the proposed
merger (the "Merger") of QELS Corp. ("Sub"), a North Carolina corporation wholly
owned by Quintiles, with and into Envoy Corporation, a Tennessee corporation
("Envoy") pursuant to the terms of the Amended and Restated Agreement and Plan
of Merger dated as of December 15, 1998 (the "Merger Agreement") by and among
Quintiles, Envoy and Sub. This opinion is being rendered pursuant to Section
7.02(f) of the Merger Agreement. All capitalized terms, unless otherwise
specified, have the meaning assigned to them in the Merger Agreement.

         In connection with this opinion, we have examined originals or copies,
certified or otherwise identified to our satisfaction, of the Merger Agreement,
the Registration Statement and such other documents as we have deemed necessary
or appropriate in order to enable us to render the opinion expressed below. In
our examination, we have assumed the genuineness of all signatures, the legal
capacity of all natural persons, the authenticity of all documents submitted to
us as originals, the conformity to original documents of all documents submitted
to us as certified, conformed or photostatic copies and the authenticity of the
originals of such copies.

         In rendering the opinion set forth below, we have relied, with your
permission, upon certain written factual representations of Quintiles, Sub and
Envoy dated as of the date of this letter. We have assumed that any
representation or statement made in connection with such representations that is
made "to the best of knowledge" or similarly qualified is correct without such
qualification. We have also assumed that when a person or entity making a
representation has represented that such person or entity either is not a party
to or does not have, or is not aware of, any plan or intention, understanding or
agreement as to a particular matter, there is in fact no such plan, intention,
understanding or agreement. We also have assumed that all such written
representations will be true as of the Effective Time.

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Quintiles Transnational Corp.
______________, 1999
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         In rendering our opinion, we have considered the applicable provisions
of the Code, the Treasury Regulations, pertinent judicial authorities,
interpretive rulings of the Internal Revenue Service and such other authorities
as we have considered relevant.

         Based upon and subject to the foregoing, we are of the opinion that (i)
the Merger will constitute a tax-free reorganization under Section 368(a) of the
Code; (ii) Quintiles, Sub and PMSI will each be a party to the reorganization
within the meaning of Section 368(b) of the Code; and (iii) the summary of
"Material Federal Income Tax Considerations" set forth in the Registration
Statement filed by Quintiles with the Securities and Exchange Commission is
accurate, subject to the assumptions, conditions and limitations set forth
therein.

         Our opinion expressed in this letter is based on current law and upon
facts and assumptions as of the date of this letter. Our opinion is subject to
change in the event of a change in the applicable law, a change in the
interpretation of the applicable law by the courts or by the Internal Revenue
Service or a change in any of the facts or assumptions upon which the opinion is
based. There is no assurance that legislative, regulatory, administrative or
judicial developments may not be forthcoming which would significantly modify
the statements or opinion expressed in this letter. Any such developments may or
may not be retroactive. This opinion represents our best legal judgment but has
no binding effect or official status of any kind. As a result, no assurance can
be given that the opinion expressed in this letter will be sustained by a court
if contested. No ruling will be obtained from the Internal Revenue Service with
respect to the Merger.

         Except as set forth above, we express no opinion as to the tax
consequences to any party, whether Federal, state, local or foreign, of the
Merger or of any transactions related to the Merger or contemplated by the
Merger Agreement. This opinion is being furnished only to you in connection with
the Merger and solely for your benefit in connection therewith and may not be
used or relied upon for any other purpose and may not be circulated, quoted or
otherwise referred to for any other purpose without our express written consent.
We hereby acknowledge and consent to Quintiles's filing of this opinion as an
exhibit to the Registration Statement with the Securities and Exchange
Commission. In giving such consent, we do not thereby admit that we are in the 
category of persons whose consent is required under Section 7 of the Securities 
Act of 1933, as amended, or the rules and regulations of the Securities and 
Exchange Commission promulgated thereunder.

                                     Very truly yours,



                                     SMITH, ANDERSON, BLOUNT, DORSETT,
                                     MITCHELL & JERNIGAN, L.L.P.