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                                                                     Exhibit 5.1

                       [LATHAM & WATKINS LLP LETTERHEAD]

March 28, 2003

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

          Re:   Registration Statement on Form S-4

Ladies and Gentlemen:

     In connection with the registration of 20,438,802 shares of common stock of
Intuitive Surgical, Inc. (the "Company"), par value $0.001 per share (the
"Shares"), under the Securities Act of 1933, as amended (the "Act"), by the
Company on Form S-4 (the "Registration Statement") filed with the Securities and
Exchange Commission on March 28, 2003, 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, as of the date hereof,
the Shares have been duly authorized and, upon issuance, delivery and payment
therefor in the manner contemplated by the Registration Statement, will be
validly issued, fully paid and nonassessable.

     We consent to your filing this opinion as an exhibit to the Registration
Statement and to the reference to our firm under the caption "Legal Matters" in
the prospectus included in the Registration Statement.

                                        Very truly yours,

                                        /s/ Latham & Watkins LLP







