Exhibit 31.1

                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER
                REQUIRED BY RULE 13a-14(a) (17 CFR 240.13a-14(a))


I, Miles D. White, certify that:


1. I have reviewed this quarterly report on Form 10-Q of Abbott Laboratories;

2. Based on my knowledge, this report does not contain any untrue statement of a
material fact or omit to state a material fact necessary to make the statements
made, in light of the circumstances under which such statements were made, not
misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of Abbott Laboratories
as of, and for, the periods presented in this report;

4. Abbott Laboratories' other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for Abbott Laboratories and have:

     a) Designed such disclosure controls and procedures, or caused such
     disclosure controls and procedures to be designed under our supervision, to
     ensure that material information relating to Abbott Laboratories, including
     its consolidated subsidiaries, is made known to us by others within those
     entities, particularly during the period in which this report is being
     prepared;

     b) Evaluated the effectiveness of Abbott Laboratories' disclosure controls
     and procedures and presented in this report our conclusions about the
     effectiveness of the disclosure controls and procedures, as of the end of
     the period covered by this report based on such evaluation; and

     c) Disclosed in this report any change in Abbott Laboratories' internal
     control over financial reporting that occurred during Abbott Laboratories'
     most recent fiscal quarter that has materially affected, or is reasonably
     likely to materially affect, Abbott Laboratories' internal control over
     financial reporting; and



5. Abbott Laboratories' other certifying officer and I have disclosed, based on
our most recent evaluation of internal control over financial reporting, to
Abbott Laboratories' auditors and the audit committee of Abbott Laboratories'
board of directors:

     a) All significant deficiencies and material weaknesses in the design or
     operation of internal control over financial reporting which are reasonably
     likely to adversely affect Abbott Laboratories' ability to record, process,
     summarize and report financial information; and

     b) Any fraud, whether or not material, that involves management or other
     employees who have a significant role in Abbott Laboratories' internal
     control over financial reporting.


Date: August 12, 2003                  /s/ Miles D. White
                                       ------------------------------------
                                       Miles D. White, Chairman of the Board
                                       and Chief Executive Officer