EXHIBIT 5.1

                                                             August 3, 2000

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

Dear Sirs

TYCO INTERNATIONAL LTD. ("TYCO")

   We have acted as Bermuda counsel to Tyco in connection with Amendment No. 1
to the Registration Statement on Form S-4, as amended (File Nos. 333-42128 and
333-42128-01) (the "Registration Statement") filed by Tyco and Tyco
International Group S.A., a Luxembourg company (the "Issuer" and collectively
with Tyco the "Registrants") with the United States Securities and Exchange
Commission (the "Commission") under the Securities Act of 1933, as amended, for
the registration of (Euro)600,000,000 aggregate principal amount of the
Issuer's 6 1/8% Notes due 2007 (the "Debt Securities") and the guarantees (the
"Guarantees") of the Debt Securities by Tyco, to be issued upon consummation of
the exchange offer referred to in the Registration Statement (the "Exchange
Offer"). The Debt Securities to be issued upon consummation of the Exchange
Offer will be so issued pursuant to the Indenture previously filed as Exhibit
4.1 to the Registrants' Form S-3 (File Nos. 333-50855 and 333-50855-01) (the
"Indenture") among the Issuer, Tyco (as Guarantor) and the trustee thereunder
as supplemented by Supplemental Indenture No. 13 filed as Exhibit 4.2 to the
Registration Statement.

   For the purposes of this opinion we have examined and relied upon the
documents listed (which, in some cases, are also defined) in the Schedule to
this opinion, (the "Documents").

Assumptions

   In stating our opinion we have assumed:-

     (a) the authenticity, accuracy and completeness of all documents
  submitted to us as originals and the conformity to authentic original
  documents of all documents submitted to us as certified, conformed,
  notarised or photostatic copies;

     (b) the genuineness of all signatures on the documents we have reviewed;

     (c) the authority, capacity and power of each of the persons, other than
  Tyco, signing the documents which we have reviewed;

     (d) that any factual statements made in the Registration Statement, any
  of the exhibits thereto and any certificates examined by us are true,
  accurate and complete in all respects material to this opinion;

     (e) that there are no provisions of the laws or regulations of any
  jurisdiction other than Bermuda which would be contravened by the execution
  or delivery of the Guarantees or which would have any implication in
  relation to the opinion expressed herein and that, in so far as any
  obligation under, or action to be taken under, the Guarantees is required
  to be performed or taken in any jurisdiction outside Bermuda, the
  performance of such obligation or the taking of such action will constitute
  a valid and binding obligation of each of the parties thereto under the
  laws of that jurisdiction and will not be illegal by virtue of the laws of
  that jurisdiction;

     (f) that the records which were the subject of the Searches were
  complete and accurate at the date of such Searches and disclosed all
  information which is material for the purposes of this opinion and such
  information has not since such date been materially altered;



     (g) that the Tyco Board Resolutions and the Issuer's Board Resolutions
  are in full force and effect and have not been rescinded, either in whole
  or in part, and accurately record the resolutions passed by the respective
  Board of Directors of Tyco and the Issuer in meetings which were duly
  convened and at which a duly constituted quorum was present and voting
  throughout;

     (h) that each Director of Tyco and the Issuer, when the Board of
  Directors of Tyco and the Issuer passed the Tyco Board Resolutions and the
  Issuer's Board Resolutions respectively, discharged his fiduciary duty owed
  to Tyco or the Issuer respectively and acted honestly and in good faith
  with a view to the respective best interests of Tyco or the Issuer;

     (i) that Tyco has entered into its obligations under the Guarantees in
  good faith for the purpose of carrying on its business and that, at the
  time it did so, there were reasonable grounds for believing that the
  transactions contemplated by the Guarantees would benefit Tyco; and

     (j) that the Purchase Agreement, the Registration Rights Agreement, the
  Indenture and the Supplemental Indenture constitute legal, valid and
  binding obligations of each of the parties thereto, enforceable in
  accordance with their terms, under the laws of the State of New York by
  which they are expressed to be governed.

Opinion

   Based upon and subject to the foregoing and subject to the reservations set
out below and to any matters not disclosed to us, we are of the opinion that:-

     (1) Tyco is an exempted company incorporated with limited liability and
  existing under the laws of Bermuda. Tyco is in good standing under the laws
  of Bermuda.

     (2) All necessary corporate action required to be taken pursuant to
  Bermuda law by Tyco in connection with the issue by Tyco of the Guarantees
  in accordance with the provisions of the Indenture and the Supplemental
  Indenture and upon the terms of the Exchange Offer set forth in the
  Registration Statement has been taken by or on behalf of Tyco.

     (3) There are no taxes, duties or other charges payable to or chargeable
  by the Government of Bermuda, or any authority or agency thereof in respect
  of the issue of the Guarantees.

Reservations

   We have the following reservations:-

     (a) We express no opinion as to any law other than Bermuda law and none
  of the opinions expressed herein relates to compliance with or matters
  governed by the laws of any jurisdiction except Bermuda. This opinion is
  limited to Bermuda law as applied by the Courts of Bermuda at the date
  hereof.

     (b) In paragraph (1) above, the term "good standing" means that Tyco has
  neither failed to make any filing with any Bermuda governmental authority
  nor to pay any Bermuda government fee or tax, which might make it liable to
  be struck off the Registrar of Companies and thereby cease to exist under
  the laws of Bermuda.


Disclosure

   This opinion is addressed to you solely for your benefit and is neither to
be transmitted to any other person, nor relied upon by any other person or for
any other purpose nor quoted or referred to in any public document nor filed
with any governmental agency or person, without our prior written consent,
except as may be required by law or regulatory authority. Further, this opinion
speaks as of its date and is strictly limited to the matters stated herein.

   We hereby consent to the inclusion of the opinion as an exhibit to the
Registration Statement and the references to our Firm under the caption "Legal
Matters" in the prospectus included as part of the Registration Statement.

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   This opinion is governed by and is to be construed in accordance with
Bermuda law. It is given on the basis that it will not give rise to any legal
proceedings with respect thereto in any jurisdiction other than Bermuda.

                                          Yours faithfully,

                                          /s/ Appleby Spurling & Kempe

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                                    SCHEDULE

  (i) The Registration Statement (excluding exhibits thereto than those
      specifically mentioned below);

  (ii) the executed Indenture, the executed Supplemental Indenture and the
       executed Guarantees;

 (iii) the Purchase Agreement filed as Exhibit 4.3 to the Registration
       Statement;

 (iv) the executed Registration Rights Agreement, filed as Exhibit 4.4 to the
      Registration Statement;

  (v) a copy of the Certificate of Byron S. Kalogerou, Vice President and
      Assistant Secretary of Tyco dated August 2, 2000 attaching the
      resolutions of the Board of Directors of Tyco, passed on November 3, 1999
      (the "Tyco Board Resolutions");

 (vi)  a copy of the Certificate of Richard W. Brann, Managing Director of the
       Issuer, dated April 4, 2000, as to the resolutions of the Board of
       Directors of the Issuer passed on March 16, 2000 (the "Issuer's Board
       Resolutions");

 (vii) the entries and filings shown in respect of the Company on the file of
       the Company maintained in the Register of Companies at the office of the
       Registrar of Companies in Hamilton, Bermuda, as revealed by a search on
       August 1, 2000 (the "Company Search");

(viii) the entries and filings shown in the Supreme Court Causes Book
       maintained at the Registry of the Supreme Court in Hamilton, Bermuda, as
       revealed by a search on August 1, 2000 in respect of the Company, (the
       "Litigation Search");

   (The Company Search and the Litigation Search are collectively referred to
      as the "Searches");

  (ix) the Certificate of Incorporation, Memorandum of Association and Bye-laws
       of Tyco (collectively referred to as the "Constitutional Documents").

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