Exhibit 8.1

                   [Letterhead of Wilmer, Cutler & Pickering]

                                December 8, 2000

Tyco International Ltd.
The Zurich Centre, Second Floor
90 Pitts Bay Road
Pembroke HM 08, Bermuda

Ladies and Gentlemen:

   We have acted as counsel to Tyco International Ltd. (the "Company") in
connection with the preparation and filing of a Registration Statement on Form
S-3 (the "Registration Statement") pursuant to the Securities Act of 1933, as
amended (the "Securities Act"), relating to the registration under the
Securities Act of $4,657,500,000 aggregate principal amount at maturity of the
Company's Liquid Yield Option Notes due 2020 (Zero Coupon--Senior) (the
"LYONs") which are convertible from time to time into shares of the Company's
common stock.

   In connection with our opinion, we have examined the Registration Statement,
including the exhibits thereto, and such other documents, corporate records and
instruments, and have examined such laws and regulations, as we have deemed
necessary for the purposes of this opinion. In such examination, we have
assumed the genuineness of all signatures, the authenticity of all documents
submitted to us as originals, the conformity to the original documents of all
documents submitted to us as copies and the authenticity of the originals of
such latter documents.

   This opinion is based on relevant provisions of the Internal Revenue Code of
1986, as amended, the Treasury Regulations issued thereunder, court decisions,
and administrative determinations as currently in effect, all of which are
subject to change, prospectively or retroactively, at any time. We undertake no
obligation to update or supplement this opinion to reflect any changes in laws
that may occur after the date hereof.

   Based on and subject to the foregoing, we hereby confirm that the discussion
set forth in the Registration Statement under the headings "Certain Bermuda and
United States Federal Income Tax Consequences--United States," "--U.S.
Holders," and "--Non-U.S. Holders," subject to the qualifications set forth
therein, to the extent that it constitutes matters of law, summaries of legal
matters, or legal conclusions with respect thereto under the laws of the United
States, is a fair summary in all material respects.

   We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the use of our name under the heading "Certain
Bermuda and United States Federal Income Tax Consequences--United States" in
the Registration Statement. In giving this consent, we do not thereby admit
that we are included in the category of persons whose consent is required under
Section 7 of the Securities Act or the rules and regulations promulgated
thereunder.

                                          Very truly yours,

                                          Wilmer, Cutler & Pickering

                                                    /s/ Robert Stack
                                          By: _________________________________
                                                      Robert Stack
                                                        A Partner