EXHIBIT 5.1
                                                                     -----------


                                                                December 9, 2003


Boston Scientific Corporation
One Boston Scientific Place
Natick, MA 01760-1537


       RE:  BOSTON SCIENTIFIC CORPORATION
            2003 LONG-TERM INCENTIVE PLAN
            401(K) RETIREMENT SAVINGS PLAN

Gentlemen:

       This opinion is furnished in connection with the registration, pursuant
to a Registration Statement on Form S-8 under the Securities Act of 1933, as
amended (the "Act"), to be filed with the Securities and Exchange Commission on
or about December 9, 2003,(the "Registration Statement"), of 60,000,000 shares
(the "Shares") of the Common Stock, par value $.01 per share (the "Common
Stock"), of Boston Scientific Corporation, a Delaware corporation (the
"Company"), which have been or will issued pursuant to the Company's 2003
Long-Term Incentive Plan and 401(k) Retirement Savings Plan (the "Plans"). The
Company's 2003 Long-Term Incentive Plan was approved by the Company's Board of
Directors on February 25, 2003 and by the Company's stockholders on May 6, 2003.

       I have acted as counsel to the Company in connection with the foregoing
registration of the Shares. I or attorneys in my office have examined and relied
upon the originals or copies, certified or otherwise identified to our
satisfaction, of such records, instruments, certificates, memoranda and other
documents as we have deemed necessary or advisable for purposes of this opinion
and have assumed, without independent inquiry, the accuracy of those documents.
In that examination, we have assumed the genuineness of all signatures, the
conformity to the originals of all documents reviewed by me or by attorneys in
my office as copies, the authenticity and completeness of all original documents
reviewed by me or by attorneys in my office in original or copy form and the
legal competence of each individual executing such documents. I have further
assumed that all options and shares to be granted pursuant to the Plans will be
validly granted in accordance with the terms of the respective Plans and that
all Shares to be issued upon exercise of such options or otherwise will be
issued in accordance with such options and the respective Plans.

       Based upon the foregoing, I am of the opinion that, upon the issuance and
delivery of the Shares in accordance with the terms of such options and the
respective Plans, and as described in the Registration Statement, the Shares
will be validly issued, fully paid and non-assessable shares of the Company's
Common Stock.

       This opinion is limited solely to the Delaware General Corporation Law,
as applied by courts located in Delaware, the applicable provisions of the
Delaware Constitution and the reported judicial decisions interpreting those
laws.

       I consent to the filing of a copy of this opinion as an exhibit to the
Registration Statement.

                                            Very truly yours,


                                            /s/ Lawrence J. Knopf
                                            -----------------------------------
                                            Lawrence J. Knopf
                                            Vice President, Assistant Secretary
                                            and Assistant General Counsel