1
                                                                   EXHIBIT 5.01



                           [SMITH ANDERSON LETTERHEAD]




                                 May 8, 1997











                                                                (919) 821-6668






Quintiles Transnational Corp.
4709 Creekstone Drive
Riverbirch Building, Suite 300
Durham, North Carolina 27703-8411

         Re:  Registration Statement on Form S-4

Ladies and Gentlemen:

         We are counsel for Quintiles Transnational Corp. (the "Company") in
connection with the issuance by the Company of up to 350,000 shares of the
Company's Common Stock, $0.01 par value per share to be issued in exchange for
the shares of Common Stock and Series A Preferred Stock of CerebroVascular
Advances, Inc. ("CVA") outstanding as of the effective date of the merger of CVA
with and into CVA Acquisition Corp., a North Carolina corporation which has not
engaged in any material operations since its incorporation and is a wholly owned
subsidiary of the Company (the "Merger"). These shares are described in the
Company's Registration Statement on Form S-4 to be filed with the Securities and
Exchange Commission (the "Commission") under the Securities Act of 1933, as
amended (the "Act"), with which this opinion will be filed as an exhibit (the
"Registration Statement").

         We have examined the Articles of Incorporation and Bylaws of the
Company, the minutes of the meetings of the Board of Directors of the Company
relating to the authorization and the issuance of securities and such other
documents, records, and matters of law as we have deemed necessary for purposes
of this opinion. In our examination, we have assumed the genuineness of all
signatures, the authenticity of all documents as originals, the conformity to
originals of all documents submitted to us as certified copies or photocopies,
and the authenticity of the originals of such latter documents. In



   2

Quintiles Transnational Corp.
May 8, 1997
Page 2


rendering the opinion set forth below, we have relied on a certificate of a
Company officer, whom we believe is responsible.

         Based upon the foregoing, it is our opinion, as of the date hereof,
that the 350,000 shares of Common Stock of the Company which are being
registered pursuant to the Registration Statement are duly authorized and, when
issued and delivered in exchange for the shares of CVA Common Stock and Series A
Preferred Stock surrendered in the Merger, as contemplated by the Registration
Statement, such shares will be validly issued, fully paid and nonassessable.

         The opinion expressed herein does not extend to compliance with state
and federal securities laws relating to the sale of these securities.

         We hereby consent to the reference to our firm under the heading "Legal
Matters" in the Registration Statement and to the filing of this opinion as
Exhibit 5.01 to the Registration Statement. Such consent shall not be deemed to
be an admission that this firm is within the category of persons whose consent
is required under Section 7 of the Act, or the regulations promulgated by the
Commission pursuant to such Act.

         This opinion is rendered solely for your benefit in connection with the
transactions described above. This opinion may not be used or relied upon by any
other person without our prior written consent.


                                   Sincerely yours,

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