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                                                                       EXHIBIT 5


                          July 15, 1996



ClinTrials Research Inc.
One Burton Hills Boulevard
Suite 210
Nashville, Tennessee 37215

Ladies and Gentlemen:

       We have acted as counsel to ClinTrials Research Inc., a Delaware
corporation (the "Company"), in connection with the registration of up to
1,350,000 shares of the Company's common stock (the "Shares") to be issued under
the provisions of the Company's 1989 Stock Plan, as amended, pursuant to a
registration statement on Form S-8 filed with the Securities and Exchange
Commission on July 15, 1996 (the registration statement, as it may be amended,
is hereinafter referred to as the "Registration Statement").  This firm hereby
consents to the filing of this opinion as an exhibit to the Registration
Statement and with agencies of such states and other jurisdictions as may be
necessary in the course of complying with the laws of such states and
jurisdictions regarding the offer and sale of the Shares in accordance with the
Registration Statement.

       We have examined copies of the Company's Restated Certificate of
Incorporation and Bylaws, such records of proceedings of the Company's Board of
Directors as we consider appropriate, and the Registration Statement.

       In stating our opinion, we have assumed:  (i) that all signatures are
genuine, all documents submitted to us as originals are authentic, and all
documents submitted to us as copies conform to authentic original documents; and
(ii) that the parties to such documents have the legal right and power under all
applicable laws, regulations and agreements to enter into, execute, deliver and
perform their respective obligations thereunder.

       On the basis of such review, subject to the limitations expressed herein,
we are of the opinion, as of the date hereof,

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that the Shares, when issued, sold, and delivered pursuant to the Registration
Statement will be validly issued, fully paid and non-assessable.

       Our opinion herein is limited solely to the laws of the United States of
America and the corporate law of the State of Delaware.  In rendering the
opinion set forth herein, we have relied upon the documents referenced above and
such other information as we have deemed necessary, but we have made no
independent verification or investigation of factual matters pertaining thereto
or to the Company.  The opinion expressed herein is subject to applicable
bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance and
similar laws now or hereafter in effect relating to or affecting the rights of
creditors generally; judicial discretion; and equitable principles, whether
applied pursuant to a proceeding at law or in equity.  No opinion is expressed
with respect to the availability of equitable remedies.

                                     Sincerely,

                                     HARWELL HOWARD HYNE
                                     GABBERT & MANNER, P.C.