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                                                                     EXHIBIT 5.1

                          [Latham & Watkins Letterhead]

                                 July 21, 2003

Intuitive Surgical, Inc.
950 Kifer Road
Sunnyvale, California  94086

Ladies and Gentlemen:

      In connection with the registration under the Securities Act of 1933, as
amended, by Intuitive Surgical, Inc., a Delaware corporation (the "Company"), on
Form S - 8 to be filed with the Securities and Exchange Commission on July 21,
2003 (the "Registration Statement") of an aggregate 1,500,000 shares of common
stock, $0.001 par value (the "Shares"), of the Company issuable pursuant to
outstanding options under Computer Motion, Inc.'s Tandem Stock Option Plan and
1997 Stock Incentive Plan (the "Plans"), as assumed by the Company in connection
with the Company's acquisition of Computer Motion, Inc., you have requested our
opinion with respect to the matters set forth below.

      In our capacity as your special counsel in connection with such
registration, we are familiar with the proceedings taken and proposed to be
taken by the Company in connection with the authorization, issuance and sale of
the Shares. In addition, we have made such legal and factual examinations and
inquiries, including an examination of originals or copies certified or
otherwise identified to our satisfaction, of such documents, corporate records
and instruments as we have deemed necessary or appropriate for purposes of this
opinion.

      In our examination, we have assumed the genuineness of all signatures, the
authenticity of all documents submitted to us as originals, and the conformity
to authentic original documents of all documents submitted to us as copies.

      We are opining herein as to the effect on the subject transaction only of
the General Corporation Law of the State of Delaware, and we express no opinion
with respect to the applicability thereto, or the effect thereon, of the laws of
any other jurisdiction or, in the case of Delaware, any other laws, or as to any
matters of municipal law or the laws of any local agencies within any state.

      Subject to the foregoing, it is our opinion that the Shares to be issued
under the Plans have been duly authorized, and upon the issuance and delivery of
the Shares in the manner contemplated by the Plans, and assuming the Company
completes all actions and proceedings required on its part to be taken prior to
the issuance and delivery of the Shares pursuant to the terms of the Plans,
including, without limitation, collection of required payment for the Shares,
the Shares will be validly issued, fully paid and nonassessable.

      We consent to your filing this opinion as an exhibit to the Registration
Statement.

                                              Very truly yours,

                                              /s/ Latham & Watkins LLP

