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                                                                       Exhibit 5


December 18, 2001



Abbott Laboratories
100 Abbott Park Road
Abbott Park, Illinois 60064-6400

Dear Sir or Madam:

I am Divisional Vice President and Assistant Secretary of Abbott
Laboratories, an Illinois corporation, am a member of the Bar of the State of
Illinois, and have advised Abbott Laboratories in connection with the
proposed offering of 1,000,000 shares of the common stock, without par value,
of Abbott Laboratories (the "Shares") pursuant to the Abbott Laboratories
Affiliate Employee Stock Purchase Plan (the "Plan"), which Plan is the
subject of the Registration Statement on Form S-8 to which this is an exhibit
(the "Registration Statement"). The Registration Statement is being filed
with the Securities and Exchange Commission under the Securities Act of 1933,
as amended. In connection with the proposed offering and registration, I, or
members of my staff, have examined or are otherwise familiar with:

     (i)   the Registration Statement,

     (ii)  the Restated Articles of Incorporation of Abbott Laboratories,

     (iii) the By-laws of Abbott Laboratories,

     (iv)  the Plan, and

     (v)   the minutes of all of the meetings of the board of directors of
           Abbott Laboratories relating to the establishment of the Plan.

In addition, I have made such other examinations and have ascertained or
verified to my satisfaction such additional facts as I deem pertinent under
the circumstances.

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Abbott Laboratories
December 18, 2001
Page Two


On the basis of such examinations, I am of the opinion that:

     1.  Abbott Laboratories is a corporation duly organized and validly
         existing under the laws of the State of Illinois with full corporate
         power and authority to issue the Shares and having authorized
         capital of 2,400,000,000 common shares, of which 1,553,656,141 were
         outstanding on November 30, 2001, and 1,000,000 cumulative preferred
         shares, par value $1.00 per share, none of which are outstanding.

     2.  As of December 14, 2001, 1,000,000 additional shares of Common Stock
         were reserved for issuance upon the exercise of options or the grant
         of benefits under the Plan.

     3.  All of the legal and corporate proceedings that are necessary in
         connection with the grant of benefits under the Plan and the
         authorization and issuance of the Shares pursuant thereto have been
         duly taken and, after those Shares have been issued in accordance
         with the provisions of the Plan, they will be legally issued, fully
         paid and nonassessable outstanding common shares of Abbott
         Laboratories.

I hereby consent to the use of this legal opinion as an exhibit to the
Registration Statement to be filed with the Securities and Exchange
Commission under the Securities Act of 1933, as amended.

Very truly yours,

/s/ Brian J. Smith

BJS:pk