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                                                                   Exhibit 1.1


                                  [_________] Shares

                               INTUITIVE SURGICAL, INC.

                      COMMON STOCK (PAR VALUE $0.001 PER SHARE)

                                UNDERWRITING AGREEMENT

                                     _____, 1998




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                                                                    _____, 1998


Morgan Stanley & Co. Incorporated
Bear, Stearns & Co. Inc.
BT Alex. Brown Incorporated
c/o Morgan Stanley & Co. Incorporated
    1585 Broadway
    New York, New York 10036

Ladies and Gentlemen:

            Intuitive Surgical, Inc., a Delaware corporation (the "Company"),
proposes to issue and sell to the several Underwriters named in Schedule I
hereto (the "Underwriters"), an aggregate of [________] shares of the Common
Stock (par value $0.001 per share) of the Company (the "Firm Shares").  The
Company also proposes to sell to the several Underwriters not more than an
additional [________] shares of its Common Stock (par value $0.001 per share)
(the "Additional Shares"), if and to the extent that you, as Managers of the
offering, shall have determined to exercise, on behalf of the Underwriters, the
right to purchase such shares of Common Stock granted to the Underwriters in
Section 2 hereof. The Firm Shares and the Additional Shares are hereinafter
collectively referred to as the "Shares." The shares of Common Stock (par value
$0.001 per share) of the Company to be outstanding after giving effect to the
sales contemplated hereby are hereinafter referred to as the "Common Stock."

            The Company has filed with the Securities and Exchange Commission
(the "Commission") a registration statement, including a prospectus, relating to
the Shares. The registration statement as amended at the time it becomes
effective, including the information (if any) deemed to be part of the
registration statement at the time of effectiveness pursuant to Rule 430A under
the Securities Act of 1933, as amended (the "Securities Act"), is hereinafter
referred to as the "Registration Statement;" the prospectus in the form first
used to confirm sales of Shares is hereinafter referred to as the "Prospectus."
If the Company has filed an abbreviated registration statement to register
additional shares of Common Stock pursuant to Rule 462(b) under the Securities
Act (the "Rule 462 Registration Statement"), then any reference herein to the
term "Registration Statement" shall be deemed to include such Rule 462
Registration Statement.

            As part of the offering contemplated by this Agreement, Morgan
Stanley & Co. Incorporated ("Morgan Stanley") has agreed to reserve out of the
Shares set forth opposite its name on Schedule I to this Agreement, up to
[________] shares, for sale to the Company's employees, officers, and directors
and other parties associated with the Company (collectively, "Participants"), as
set forth in the Prospectus under the heading "Underwriting" (the "Directed
Share Program").  The Shares to be sold by Morgan Stanley pursuant to the
Directed Share Program (the "Directed Shares") will be sold by Morgan Stanley
pursuant to this Agreement at the public offering price.  Any Directed Shares
not orally confirmed for purchase by any Participants by the end of the first
business day after the date on which this Agreement is executed will be offered
to the public by Morgan Stanley as set forth in the Prospectus.

            1.    REPRESENTATIONS AND WARRANTIES OF THE COMPANY.  The Company
represents and warrants to and agrees with each of the Underwriters that:

            (a)   The Registration Statement has become effective; no stop order
      suspending the effectiveness of the Registration Statement is in effect,
      and no proceedings for such purpose are pending before or, to the
      Company's knowledge, threatened by the Commission.

            (b)   (i) The Registration Statement, when it became effective, did
      not contain and, as amended or supplemented, if applicable, will not
      contain any untrue statement of a material fact or omit to state a
      material fact required to be stated therein or necessary to make the
      statements therein not misleading, (ii) the Registration Statement and the
      Prospectus comply and, as amended or supplemented, if applicable, will
      comply in all material respects with the Securities Act and the applicable
      rules and regulations of the Commission thereunder, and (iii) the
      Prospectus does not contain and, as supplemented,

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      if applicable, will not contain any untrue statement of a material fact or
      omit to state a material fact necessary to make the statements therein, in
      the light of the circumstances under which they were made, not misleading,
      except that the representations and warranties set forth in this
      Section l(b) do not apply to statements or omissions in the Registration
      Statement or the Prospectus based upon information relating to any
      Underwriter furnished to the Company in writing by such Underwriter
      through you expressly for use therein.

            (c)   The Company has been duly incorporated, is validly existing as
      a corporation in good standing under the laws of the jurisdiction of its
      incorporation, has the corporate power and authority to own its property
      and to conduct its business as described in the Prospectus and is duly
      qualified to transact business and is in good standing in each
      jurisdiction in which the conduct of its business or its ownership or
      leasing of property requires such qualification, except to the extent that
      the failure to be so qualified or be in good standing would not have a
      material adverse effect on the Company.

            (d)   The Company does not own any equity or capital interests in
      any corporation, partnership, joint venture, association or other entity.

            (e)   This Agreement has been duly authorized, executed and
      delivered by the Company.

            (f)   The authorized capital stock of the Company conforms as to
      legal matters in all material respects to the description thereof
      contained in the Prospectus.

            (g)   The shares of Common Stock outstanding prior to the issuance
      of the Shares to be sold by the Company have been duly authorized and are
      validly issued, fully paid and non-assessable.  Except as set forth in the
      Prospectus and other than options to purchase [________] shares of the
      Company's Common Stock granted to employees pursuant to the Company's 1998
      Equity Incentive Plan (the "1998 Incentive Plan"), the Company's 1998
      Employee Stock Purchase Plan (the "1998 Purchase Plan"), the Company's
      1998 Non-Employee Directors' Stock Option Plan (the "1998 Directors'
      Plan") and a warrant to purchase 11,000 shares, all as described in the
      Prospectus, the Company has no outstanding options to purchase, or any
      preemptive rights or other rights to subscribe for or to purchase, any
      securities or obligations convertible into, or any contracts or
      commitments to issue or sell, shares of its capital stock or any such
      options, rights, convertible securities or obligations.  All outstanding
      shares of capital stock and options and other rights to acquire capital
      stock have been issued in compliance with the registration and
      qualification provisions of all applicable securities laws (or applicable
      exemptions thereof) and were not issued in violation of any preemptive
      rights, rights of first refusal and other similar rights.

            (h)   The Shares have been duly authorized, and when issued and
      delivered in accordance with the terms of this Agreement, will be validly
      issued, fully paid and non-assessable, and the issuance of such Shares
      will not be subject to any preemptive or similar rights.

            (i)   The execution and delivery by the Company of, and the
      performance by the Company of its obligations under, this Agreement will
      not contravene any provision of the Company's Amended and Restated
      Certificate of Incorporation, as amended, or bylaws of the Company or any
      agreement or other instrument binding upon the Company that is material to
      the Company or any judgment, order or decree of any governmental body,
      agency or court having jurisdiction over the Company, and no consent,
      approval, authorization or order of, or qualification with, any
      governmental body or governmental agency is required for the performance
      by the Company of its obligations under this Agreement, except such as may
      be required by the National Association of Securities Dealers ("NASD") or
      the securities or Blue Sky laws of the various states or international
      jurisdictions in connection with the offer and sale of the Shares.

            (j)   There has not occurred any material adverse change, or any
      development involving a prospective material adverse change, in the
      condition, financial or otherwise, or in the earnings, business or
      operations of the Company from that set forth in the Prospectus.

            (k)   There are no legal or governmental proceedings pending or, to
      the Company's knowledge,  threatened to which the Company is a party or to
      which any of the properties of the Company

                                          2
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      is subject that are required to be described in the Registration Statement
      or the Prospectus and are not so described or any statutes, regulations,
      contracts or other documents that are required to be described in the
      Registration Statement or the Prospectus or documents required to be filed
      as exhibits to the Registration Statement that are not described or filed
      as required.

            (l)   Each preliminary prospectus filed as part of the Registration
      Statement as originally filed or as part of any amendment thereto, or
      filed pursuant to Rule 424 or Rule 462 under the Securities Act, complied
      when so filed in all material respects with the Securities Act and the
      applicable rules and regulations of the Commission thereunder.

            (m)   The Company is not and, after giving effect to the offering
      and sale of the Shares and the application of the proceeds thereof as
      described in the Prospectus, will not be an "investment company" or an
      entity "controlled" by an "investment company" as such terms are defined
      in the Investment Company Act of 1940, as amended.

            (n)   There is no owner of any securities of the Company who has any
      right, not effectively satisfied or waived, to require registration of any
      shares of capital stock of the Company in connection with the filing of
      the Registration Statement or the sale of the Shares thereunder.  There
      are no contracts, agreements or understandings between the Company and any
      person granting such person the right to require the Company to file a
      registration statement under the Securities Act with respect to any
      securities of the Company or to require the Company to include such
      securities with the Shares registered pursuant to the Registration
      Statement, except in each case as described in the Prospectus.

            (o)   The Company (i) is in compliance with any and all applicable
      foreign, federal, state and local laws and regulations relating to the
      protection of human health and safety, the environment or hazardous or
      toxic substances or wastes, pollutants or contaminants ("Environmental
      Laws"), (ii) has received all permits, licenses or other approvals
      required of them under applicable Environmental Laws to conduct its
      respective business and (iii) is in compliance with all terms and
      conditions of any such permit, license or approval, except where such
      noncompliance with Environmental Laws, failure to receive required
      permits, licenses or other approvals or failure to comply with the terms
      and conditions of such permits, licenses or approvals would not, singly or
      in the aggregate, have a material adverse effect on the Company.

            (p)   There are no costs or liabilities associated with
      Environmental Laws (including, without limitation, any capital or
      operating expenditures required for clean-up, closure of properties or
      compliance with Environmental Laws or any permit, license or approval, any
      related constraints on operating activities and any potential liabilities
      to third parties) which would, singly or in the aggregate, have a material
      adverse effect on the Company.

            (q)   The Company has complied with all provisions of
      Section 517.075, Florida Statutes relating to doing business with the
      Government of Cuba or with any person or affiliate located in Cuba.

            (r)   The Company has notified each holder of a currently
      outstanding option issued under the 1998 Incentive Plan, 1998 Purchase
      Plan, or the 1998 Directors' Plan and each person who has acquired shares
      of Common Stock pursuant to the exercise of any option granted under the
      1998 Incentive Plan, 1998 Purchase Plan, or the 1998 Directors' Plan, that
      none of such options or shares may be sold or otherwise transferred or
      disposed of for a period of 180 days after the date of the initial public
      offering of the Shares and that the Company has the right to impose
      stop-transfer instructions with the Company's transfer agent in order to
      enforce the foregoing lock-up provision.

            (s)   As of the date the Registration Statement became effective,
      the Common Stock was authorized for quotation on The Nasdaq National
      Market upon official notice of issuance.

            (t)   The financial statements, including the notes thereto,
      included in the Registration Statement and the Prospectus fairly present,
      in all material respects, the financial position of the Company as of the
      dates indicated and the results of its operations for the periods
      specified; said financial statements

                                          3
<PAGE>

      have been prepared in conformity with generally accepted accounting
      principles applied on a consistent basis.

            (u)   Subsequent to the respective dates as of which information is
      given in the Registration Statement and the Prospectus, (1) the Company
      has not incurred any material liability or obligation, direct or
      contingent, nor entered into any material transaction not in the ordinary
      course of business; (2) the Company has not purchased any of its
      outstanding capital stock, nor declared, paid or otherwise made any
      dividend or distribution of any kind on its capital stock other than
      ordinary and customary dividends; and (3) there has not been any material
      change in the capital stock, short-term debt or long-term debt of the
      Company, except for options or warrants to purchase common stock which
      have been exercised on or after [May 31, 1998], in each case as described
      or contemplated in the Prospectus.


            (v)   The Company does not own any real property.  The Company has
      good and marketable title in fee simple to all personal property owned by
      it which is material to the business of the Company, in each case free and
      clear of all liens, encumbrances and defects except such as are described
      in the Prospectus or such as do not materially affect the value of such
      property and do not  interfere with the use made and proposed to be made
      of such property by the Company; and any real property and buildings held
      under lease by the Company are held by it under valid, subsisting and
      enforceable leases with such exceptions as are not material and do not
      interfere with the use made and proposed to be made of such property and
      buildings by the Company, in each case except as described in the
      Prospectus.

            (w)   The Company owns or possess, or can acquire on reasonable
      terms, all material patents, patent rights, licenses, inventions,
      copyrights, know-how (including trade secrets and other unpatented and/or
      unpatentable proprietary or confidential information, systems or
      procedures), trademarks, service marks and trade names currently employed
      by them in connection with the business now operated by it, and the
      Company has not received any notice of infringement of or conflict with
      asserted rights of others with respect to any of the foregoing and there
      are no legal or governmental proceedings other than patent applications
      pending relating to patent rights of the Company to which the Company is a
      party, which, singly or in the aggregate, if the subject of an unfavorable
      decision, ruling or finding, would have a material adverse affect on the
      Company.  The U.S. patents assigned to the Company are held by the
      Company, and, except as set forth in the Registration Statement and
      Prospectus, no other entity or individual has any right or claim in any of
      the applications, or any patent to be issued therefrom, by virtue of any
      contract, license or other agreement entered into between such entity or
      individual and the Company.

            (x)   No material labor dispute with the employees of the Company
      exists, except as described in the Prospectus, or, to the knowledge of the
      Company, is imminent.

            (y)   The Company is insured by the insurers of recognized financial
      responsibility against such losses and risks and in such amounts as are
      prudent and customary in the businesses in which they are engaged; the
      Company has not been refused any insurance coverage sought or applied for;
      and, except as described in the Prospectus, the Company has no  reason to
      believe that it will not be able to renew its existing insurance coverage
      as and when such coverage expires or to obtain similar coverage from
      similar insurers as may be necessary to continue its business at a cost
      that would not have a material adverse effect on the Company.

            (z)  The Company possesses all consents, approvals, orders,
      certificates, authorizations and permits issued by, and has made all
      declarations and filings with all appropriate federal, state or foreign
      regulatory authorities necessary to conduct its business as currently
      being conducted or as proposed in the Registration Statement to be
      conducted, except where the failure to possess such consents, approvals,
      orders, certificates, authorizations and permits or to make all
      declarations and filings would not have a material adverse effect on the
      Company, and to own, lease, license, and use their properties in the
      manner described in the Prospectus, and the Company has not received any
      notice of  proceedings relating to the revocation or modification of any
      such consent, approval, order, certificate, authorization or permit which,
      singly or in the aggregate, if the subject of an unfavorable decision,
      ruling or finding, would have a material adverse change in the condition,
      financial, or otherwise, or in the earnings, business or operations

                                          4
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      of the Company, except as described the Prospectus

            (aa)  The Company maintains a system of internal accounting controls
      sufficient to provide reasonable assurance that (1) transactions are
      executed in accordance with management's general or specific
      authorizations; (2) transactions are recorded as necessary to permit
      preparation of financial statements in  conformity with generally accepted
      accounting principles and to maintain asset accountability; (3) access to
      assets is permitted only in accordance with management's general or
      specific authorization; and (4) the recorded accountability for assets is
      compared with the existing assets at reasonable intervals and appropriate
      action is taken  with respect to any differences.

            (bb)  (i) The  Registration Statement, the Prospectus and any
      preliminary prospectus comply, and any further amendments or supplements
      thereto will comply, with any applicable laws or regulations of foreign
      jurisdictions in which the Prospectus or any preliminary prospectus, as
      supplemented, if applicable, are distributed in connection with the
      Directed Share Program, and (ii) no authorization, approval, consent,
      license, order, registration or qualification of or with any government,
      governmental instrumentality or court, other than such as have been
      obtained, is necessary under the securities laws and regulations of
      foreign jurisdictions in which the Directed Shares are offered outside the
      United States.

            (cc)  The Company has not offered, or caused the Underwriters to
      offer, Shares to any person pursuant to the Directed Share Program with
      the specific intent to unlawfully influence (i) a customer or supplier of
      the Company to alter the customer's or supplier's level or type of
      business with the Company, or (ii) a trade journalist or publication to
      write or publish favorable information about the Company or its products.

            2.    AGREEMENTS TO SELL AND PURCHASE.  The Company hereby agrees to
sell to the several Underwriters, and each Underwriter, upon the basis of the
representations and warranties herein contained, but subject to the conditions
hereinafter stated, agrees, severally and not jointly, to purchase from the
Company the respective number of Firm Shares set forth in Schedule I hereto
opposite its name at $____ a share (the "Purchase Price").

            On the basis of the representations and warranties contained in this
Agreement, and subject to its terms and conditions, the Company agrees to sell
to the Underwriters the Additional Shares, and the Underwriters shall have a
one-time right to purchase, severally and not jointly, up to [________]
Additional Shares at the Purchase Price. If you, on behalf of the Underwriters,
elect to exercise such option, you shall so notify the Company in writing not
later than 30 days after the date of this Agreement, which notice shall specify
the number of Additional Shares to be purchased by the Underwriters and the date
on which such shares are to be purchased. Such date may be the same as the
Closing Date (as defined below) but not earlier than the Closing Date nor later
than ten business days after the date of such notice.  Additional Shares may be
purchased as provided in Section 4 hereof solely for the purpose of covering
over-allotments made in connection with the offering of the Firm Shares.  If any
Additional Shares are to be purchased, each Underwriter agrees, severally and
not jointly, to purchase the number of Additional Shares (subject to such
adjustments to eliminate fractional shares as you may determine) that bears the
same proportion to the total number of Additional Shares to be purchased as the
number of Firm Shares set forth in Schedule I hereto opposite the name of such
Underwriter bears to the total number of Firm Shares.

            The Company hereby agrees that, without the prior written consent of
Morgan Stanley on behalf of the Underwriters, it will not, during the period
ending 180 days after the date of the Prospectus, (i) offer, pledge, sell,
contract to sell, sell any option or contract to purchase, purchase any option
or contract to sell, grant any option, right or warrant to purchase, lend, or
otherwise transfer or dispose of, directly or indirectly, any shares of Common
Stock or any securities convertible into or exercisable or exchangeable for
Common Stock or (ii) enter into any swap or other arrangement that transfers to
another, in whole or in part, any of the economic consequences of ownership of
the Common Stock, whether any such transaction described in clause (i) or
(ii) above is to be settled by delivery of Common Stock or such other
securities, in cash or otherwise.  The foregoing sentence shall not apply to
(A) the Shares to be sold hereunder (B) the grant of options pursuant to the
1998 Incentive Plan or the 1998 Directors Plan (C) the sale of stock pursuant to
the 1998 Purchase Plan (D) the grant of any option or warrant pursuant to an
equipment lease or accounts receivable finance transaction (E) the issuance by
the Company of shares of Common Stock upon the exercise of an option or warrant
or the conversion of a security outstanding on

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the date hereof of which the Underwriters have been advised in writing or (F) 
the sale by the Company of securities for an aggregate consideration not to 
exceed $__________, in connection with an investment by one or more strategic 
partners, provided that the holders of such securities are subject to a 
lock-up for six (6) months following the sale with substantially the same 
terms as set forth in the Lock-Up Agreements (as defined in Section 5(h) 
herein).

            3.    TERMS OF PUBLIC OFFERING.  The Company is advised by you that
the Underwriters propose to make a public offering of their respective portions
of the Shares as soon after the Registration Statement and this Agreement have
become effective as in your judgment is advisable.  The Company is further
advised by you that the Shares are to be offered to the public initially at
[$_____] a share (the "Public Offering Price") and to certain dealers selected
by you at a price that represents a concession not in excess of [$____] a share
under the Public Offering Price, and that any Underwriter may allow, and such
dealers may reallow, a concession, not in excess of [$____] a share, to any
Underwriter or to certain other dealers.

            4.    PAYMENT AND DELIVERY.  Payment for the Firm Shares shall be
made to the Company in federal or immediately available funds in New York City
against delivery of such Firm Shares for the respective accounts of the several
Underwriters at 10:00 a.m., New York City time, on [_________, 1998] or at such
other time on the same or such other date, not later than [________, 1998], as
shall be designated in writing by you. The time and date of such payment are
hereinafter referred to as the "Closing Date."

            Payment for any Additional Shares shall be made in federal or
immediately available funds in New York City against delivery of such Additional
Shares for the respective accounts of the several Underwriters at 10:00 a.m.,
New York City time, on the date specified in Section 2 or at such other time on
the same or such other date, not later than [________, 1998], as shall be
designated in writing by you. The time and date of such payment are hereinafter
referred to as the "Option Closing Date."

            Certificates for the Firm Shares and Additional Shares shall be in
definitive form and registered in such names and in such denominations as you
shall request in writing not later than one full business day prior to the
Closing Date or the Option Closing Date, as the case may be.  The certificates
evidencing the Firm Shares and Additional Shares shall be delivered to you on
the Closing Date or the Option Closing Date, as the case may be, for the
respective accounts of the several Underwriters, with any transfer taxes payable
in connection with the transfer of the Shares to the Underwriters duly paid,
against payment of the Purchase Price therefor.

            5.    CONDITIONS TO THE UNDERWRITER'S OBLIGATIONS.  The obligations
of the Company to sell the Shares to the Underwriters and the several
obligations of the Underwriters to purchase and pay for the Shares on the
Closing Date are subject to the condition that the Registration Statement shall
have become effective not later than [5:30 p.m.] (New York time) on the date
hereof.

            The several obligations of the Underwriters are subject to the
following further conditions:

            (a)   Subsequent to the execution and delivery of this Agreement and
      prior to the Closing Date:

                  (i)   there shall not have occurred any downgrading, nor shall
            any notice have been given of any intended or potential downgrading
            or of any review for a possible change that does not indicate the
            direction of the possible change, in the rating accorded any of the
            Company's securities by any "nationally recognized statistical
            rating organization," as such term is defined for purposes of Rule
            436(g)(2) under the Securities Act; and

                  (ii)  there shall not have occurred any change, or any
            development involving a prospective change, in the condition,
            financial or otherwise, or in the earnings, business or operations
            of the Company, from that set forth in the Registration Statement at
            the time it was declared effective (exclusive of any amendments or
            supplements thereto subsequent to the date of this Agreement) that,
            in your judgment, is material and adverse and that makes it, in your
            judgment, impracticable to market the Shares on the terms and in the
            manner contemplated in the Prospectus.

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            (b)   The Underwriters shall have received on the Closing Date a
      certificate, dated the Closing Date and signed by an executive officer of
      the Company on behalf of the Company, to the effect set forth in
      clause (a) above and to the effect that the representations and warranties
      of the Company contained in this Agreement are true and correct as of the
      Closing Date and that the Company has complied with all of the agreements
      and satisfied all of the conditions on its part to be performed or
      satisfied hereunder on or before the Closing Date.

            The officer signing and delivering such certificate may rely upon
      his or her knowledge as to proceedings threatened.

            (c)   The Underwriters shall have received on the Closing Date an
      opinion of Cooley Godward LLP, outside counsel for the Company, dated the
      Closing Date, to the effect that:

                  (i)   the Company has been duly incorporated, is validly
            existing as a corporation in good standing under the laws of the
            jurisdiction of its incorporation, has the corporate power authority
            to own its property and to conduct its business as described in the
            Prospectus and is duly qualified as a foreign corporation to
            transact business and is in good standing in each jurisdiction in
            which the conduct of its business or its ownership or leasing of
            property requires such qualification, except where the failure to be
            so qualified or be in good standing would not have a material
            adverse effect on the Company;

                  (ii)  the authorized, issued and outstanding capital stock of
            the Company conforms as to legal matters to the description thereof
            contained in the Prospectus under the caption "Description of
            Capital Stock";

                  (iii) the shares of Common Stock outstanding prior to the
            issuance of the Shares to be sold by the Company have been duly
            authorized and are validly issued, fully paid, and non-assessable;

                  (iv)  the Shares have been duly authorized and, when issued
            and delivered in accordance with the terms of this Agreement, will
            be validly issued, fully paid and non-assessable, and the issuance
            of such Shares will not be subject to any preemptive or similar
            rights contained in the Company's Certificate of Incorporation or
            bylaws or to such counsel's knowledge, under any agreement to which
            the Company is a party;

                  (v)   this Agreement has been duly authorized, executed and
            delivered by the Company;

                  (vi)  the execution and delivery by the Company of, and the
            performance by the Company of its obligations under, this Agreement
            will not contravene any provision of applicable law or the Amended
            and Restated Certificate of Incorporation, as amended, or bylaws of
            the Company or any agreement or other instrument binding upon the
            Company that is filed as an exhibit to the Registration Statement,
            or, to the best of such counsel's knowledge, any judgment, order or
            decree of any governmental body, agency or court having jurisdiction
            over the Company, and no consent, approval, authorization or order
            of, or qualification with, any governmental body or governmental
            agency is required for the performance by the Company of its
            obligations under this Agreement, except such as may be required by
            the NASD and securities or Blue Sky laws of the various states or
            international jurisdiction in connection with the offer and sale of
            the Shares;

                  (vii) the statements (A) in the Prospectus under the captions
            "Management--Officers and Directors (except with respect to the 
            seventh and eighth sentences of the last paragraph thereof),
            "Management--Employee Benefit Plans," "Management--Executive Officer
            and Employment Arrangements," "Certain Transactions," "Description
            of Capital Stock," "Shares Eligible for Future Sale," and
            "Business--Intellectual Property--SRI INTERNATIONAL AGREEMENT" 
            (except with respect to the first paragraph) and "--IBM AGREEMENT 
            (except with respect to the first paragraph) and (B) in the 
            Registration Statement in Items 14 and 15, in each case insofar 
            as such statements constitute summaries of the legal matters, 
            documents or

                                          7
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            proceedings referred to therein, fairly present the information
            called for with respect to such legal matters, documents and
            proceedings and fairly summarize the matters referred to therein to
            the extent required by the Act and the Rules;

                  (viii) to such counsel's knowledge, there are no legal or
            governmental proceedings pending or overtly threatened to which the
            Company is a party or to which any of the properties of the Company
            is subject that are required by the Securities Act or the rules and
            regulations thereunder (the "Act and Rules") to be described in the
            Registration Statement or the Prospectus or any statutes,
            regulations, contracts or other documents that are required to be
            described in the Registration Statement or the Prospectus or
            contracts or other documents required to be filed as exhibits to the
            Registration Statement, that are not described or filed as required
            by the Act or the Rules;

                  (ix)  the Company is not and, after giving effect to the
            offering and sale of the Shares and the application of the net
            proceeds therefrom as described in the Prospectus, will not be an
            "investment company" as such terms are defined in the Investment
            Company Act of 1940, as amended; and

                  (x)   the Registration Statement and Prospectus (except for
            the Regulatory Portion and Intellectual Property Portion (as defined
            below) and the financial statements and schedules and other
            financial and statistical data included therein as to which such
            counsel need not express any opinion) comply as to form in all
            material respects with the Securities Act and the applicable rules
            and regulations of the Commission thereunder.

                  (xi)  In addition, such counsel shall state that during the
            course of the preparation of the Registration Statement, they have
            participated in conferences with the Representatives and with
            officers and other representatives of the Company, its counsel and
            its independent public accountants at which the contents of the
            Registration Statement and Prospectus and any supplements or
            amendments thereto, and related matters were discussed.  Such
            counsel shall further state that although they have not
            independently verified and are not passing upon the accuracy,
            completeness or fairness of the statements made in the Registration
            Statement and Prospectus and any supplements or amendments thereto
            (other than as specified above in paragraphs (ii) and (vii)),
            nothing has come to their attention that has caused them to believe
            that the Registration Statement, as of the time it became effective,
            contained an untrue statement of a material fact or omitted to state
            a material fact required to be stated therein or necessary to make
            the statements therein not misleading, or that the Prospectus, as of
            its date or the date hereof, contained or contains an untrue
            statement of a material fact or omitted or omits to state a material
            fact necessary to make the statements therein, in light of the
            circumstances under which they were made, not misleading, except
            that such counsel shall express no comment with respect to the
            financial statements and schedules, related notes, other financial
            data and statistical data derived therefrom included in the
            Registration Statement and Prospectus or derived therefrom.

            (d)   The Underwriters shall have received on the Closing Date an
      opinion of Hogan & Hartsen LLP, outside regulatory counsel for the
      Company, dated the Closing Date, to the effect that the statements under
      the captions "Risk Factors--Need for Federal and State Regulatory
      Clearance or Approval," "Risk Factors--Limited Manufacturing Experience;
      Scale-Up Risk, "Business--Clinical Trials and Experience," and
      "Business--Government Regulation" (together the "Regulatory Portion"), (i)
      insofar as such statements purport to summarize applicable provisions of
      the Federal Food, Drug, and Cosmetic Act and the regulations promulgated
      thereunder, are accurate summaries in all material respects of the
      provisions purported to be summarized under such captions in the
      Prospectus and Registration Statement, and (ii) insofar as such statements
      relate to FDA regulatory matters, such counsel has no reason to believe
      that the information contained in the Regulatory Portion of the
      Registration Statement and Prospectus at the time each became effective,
      contains any untrue statement of a material fact or omits to state any
      material fact required to be stated therein or necessary to make the
      statements therein, in light of the circumstances under which they are
      made, not misleading.

                                          8
<PAGE>

            (e)   The Underwriters shall have received on the Closing Date an
      opinion of Townsend, Townsend & Crew LLP, outside intellectual property
      counsel for the Company, dated the Closing Date, to the effect that (i)
      such counsel is familiar with the technology used by the Company in its
      business and the manner of its use, (ii) such counsel has read the
      statements contained in the Registration Statement and Prospectus under
      the captions "Risk Factors--Dependence on Patents and Proprietary and
      Licensed Technology," "Risk Factors--Risks of Third-Party Claims of
      Infringement," "and "Business--Intellectual Property--Patents" (together
      the "Intellectual Property Portion"), (iii) the Intellectual Property
      Portion contains accurate descriptions of the Company's patent
      applications, issued and allowed patents, and, to the best of counsel's
      knowledge,  patents licensed to the Company, and fairly summarizes the
      legal matters, documents and proceedings relating thereto, (iv) such
      counsel is not aware of any valid United States or foreign patent that is
      or would be infringed by the activities of the Company in the manufacture,
      use or sale of any presently proposed product, as described in the
      Prospectus, (v) such counsel has reviewed the Company's patent
      applications filed in the U.S. and outside the U.S. (the "Applications"),
      and the Applications have been properly prepared and filed on behalf of
      the Company, and are being diligently pursued by the Company; the
      inventions described in the Applications are assigned or licensed to the
      Company to our knowledge, except for patents where the Company has
      obtained a field of use license, no other entity or individual has any
      right or claim in any of the inventions, Applications, or any patent to be
      issued therefrom, and in such counsel's opinion based on presently
      available information each of the Applications discloses patentable
      subject matter, (vi) such counsel not aware of any pending or threatened
      judicial or governmental proceedings relating to patents or proprietary
      information to which the Company is a party or of which an property of the
      Company is subject and such counsel is not aware of any pending or
      threatened action, suit or claim by others that the Company is infringing
      or otherwise violating any patent rights of others, nor is such counsel
      aware of any rights of third parties to any of the Company's inventions
      described in the Applications, issued, approved or licensed patents which
      could reasonably be expected to materially affect the ability of the
      Company to conduct its business as described in the Prospectus, including
      the commercialization of the "surgeon's console,"  the "patient-side cart"
      and the "resposable instruments" (each as described in the Prospectus) and
      other products currently under development, and (vii) such counsel has no
      reason to believe that the information contained in the Intellectual
      Property Portion of the Registration Statement and the Prospectus at the
      time each became effective, contained any untrue statement of a material
      fact or omitted to state any material fact necessary to make the
      statements therein, in the light of the circumstances under which they
      were made, not misleading].

            (f)   The Underwriters shall have received on the Closing Date an
      opinion of Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP,
      counsel for the Underwriters, dated the Closing Date, covering the matters
      referred to in subparagraphs (c)(iv), (c)(v), (c)(vii) (but only as to the
      statements in the Prospectus under "Description of Capital Stock" and
      "Underwriters") and Section 5(c)(x)(i) above.


            With respect to Section 5(c)(x)(i) above, Cooley Godward LLP and
      Gunderson Dettmer Stough Villeneuve Franklin & Hachigian, LLP, may state
      that their opinion and belief are based upon their participation in the
      preparation of the Registration Statement and Prospectus and any
      amendments or supplements thereto and review and discussion of the
      contents thereof, but are without independent check or verification,
      except as specified.

            The opinions of Cooley Godward LLP, Hogan & Hartsen LLP, and
      Townsend, Townsend & Crew LLP described in paragraphs (c), (d) and (e)
      above shall be rendered to the Underwriters at the request of the Company
      and shall so state therein.

            (g)   The Underwriters shall have received, on each of the date
      hereof and the Closing Date, a letter dated the date hereof or the Closing
      Date, as the case may be, in form and substance satisfactory to the
      Underwriters, from Ernst & Young LLP, independent certified public
      accountants, containing statements and information of the type ordinarily
      included in accountants' "comfort letters" to underwriters with respect to
      the financial statements and certain financial information contained in
      the

                                          9
<PAGE>

      Registration Statement and the Prospectus; PROVIDED that the letter
      delivered on the Closing Date shall use a "cut-off date" not earlier than
      the date hereof.

            (h)   The lock-up agreements (the "Lock-Up Agreements"), each
      substantially in the form attached as EXHIBIT A hereto, between you and
      certain stockholders, officers and directors of the Company relating to
      sales and certain other dispositions of shares of Common Stock or certain
      other securities, delivered to you on or before the date hereof, shall be
      in full force and effect on the Closing Date.

            The several obligations of the Underwriters to purchase Additional
Shares hereunder are subject to the delivery to you on the Option Closing Date
of such documents as you may reasonably request with respect to the good
standing of the Company, the due authorization and issuance of the Additional
Shares and other matters related to the Additional Shares.

            6.    COVENANTS OF THE COMPANY.  In further consideration of the
agreements of the Underwriters herein contained, the Company covenants with each
Underwriter as follows:

            (a)   To furnish to you, without charge, three (3) signed copies of
      the Registration Statement (including exhibits thereto) and for delivery
      to each other Underwriter a conformed copy of the Registration Statement
      (without exhibits thereto) and to furnish to you in New York City, without
      charge, prior to 10:00 a.m. local time on the second business day
      following the date of this Agreement and during the period mentioned in
      paragraph (c) below, as many copies of the Prospectus and any supplements
      thereto or to the Registration Statement as you may reasonably request.

            (b)   Before amending the Registration Statement or supplementing
      the Prospectus, to furnish to you a copy of each such proposed amendment
      or supplement and not to file any such proposed amendment or supplement to
      which you reasonably object, and to file with the Commission within the
      applicable period specified in Rule 424(b) under the Securities Act any
      prospectus required to be filed pursuant to such Rule.

            (c)   If, during such period after the first date of the public
      offering of the Shares in the opinion of counsel for the Underwriters the
      Prospectus is required by law to be delivered in connection with sales by
      an Underwriter or dealer, any event shall occur or condition exist as a
      result of which it is necessary to supplement the Prospectus in order to
      make the statements therein, in the light of the circumstances when the
      Prospectus is delivered to a purchaser, not misleading, or if, in the
      opinion of counsel for the Underwriters, it is necessary to supplement the
      Prospectus to comply with applicable law, forthwith to prepare, file with
      the Commission and furnish, at its own expense, to the Underwriters and to
      the dealers (whose names and addresses you will furnish to the Company) to
      which Shares may have been sold by you on behalf of the Underwriters and
      to any other dealers upon request, either such supplements to the
      Prospectus so that the statements in the Prospectus as so supplemented
      will not, in the light of the circumstances when the Prospectus is
      delivered to a purchaser, be misleading or so that the Prospectus, as
      supplemented, will comply with law.

            (d)   To the extent necessary to comply with applicable law, to
      endeavor to qualify the Shares for offer and sale under the securities or
      Blue Sky laws of such jurisdictions as you shall reasonably request.

            (e)   To make generally available to the Company's security holders
      and to you as soon as practicable an earnings statement of the Company
      that satisfies Section 11(a) of the Securities Act and the rules and
      regulations of the Commission thereunder.

            (f)   Whether or not the transactions contemplated in this Agreement
      are consummated or this Agreement is terminated, to pay or cause to be
      paid all expenses incident to the performance of its obligations under
      this Agreement, including: (i) the fees, disbursements and expenses of the
      Company's counsel and the Company's accountants in connection with the
      registration and delivery of the Shares under the Securities Act and all
      other fees or expenses in connection with the preparation and filing of
      the Registration Statement, any preliminary prospectus, the Prospectus and
      amendments and supplements to

                                          10
<PAGE>

      any of the foregoing, including all printing costs associated therewith,
      and the mailing and delivering of copies thereof to the Underwriters and
      dealers, in the quantities hereinabove specified, (ii) all costs and
      expenses related to the transfer and delivery of the Shares to the
      Underwriters, including any transfer or other taxes payable thereon,
      (iii) the cost of printing or producing any Blue Sky memorandum in
      connection with the offer and sale of the Shares under state securities
      laws, including filing fees and the reasonable fees and disbursements of
      counsel for the Underwriters in connection with the Blue Sky memorandum,
      (iv) all filing fees and reasonable disbursements of counsel to the
      Underwriters incurred in connection with the review and qualification of
      the offering of the Shares by the National Association of Securities
      Dealers, Inc., (v) all fees and expenses in connection with the
      preparation and filing of the registration statement on Form 8-A relating
      to the Common Stock and all costs and expenses incident to listing the
      Shares on the Nasdaq National Market, (vi) the cost of printing 
      certificates representing the Shares, (vii) the costs and charges of any
      transfer agent, registrar or depositary, (viii) the costs and expenses of
      the Company associated with the production of road show slides and
      graphics, fees and expenses of any consultants engaged in connection with
      the road show presentations with the prior approval of the Company, travel
      and lodging expenses of officers of the Company and any such consultants,
      and the Company's pro rata cost of any aircraft chartered in connection
      with the road show, (ix) all other costs and expenses incident to the
      performance of the obligations of the Company hereunder for which
      provision is not otherwise made in this Section, and (x) all fees and
      disbursements of counsel incurred by the Underwriters in connection with
      the Directed Share Program and stamp duties, similar taxes or duties or
      other taxes, if any, incurred by the Underwriters in connection with the
      Directed Share Program. It is understood, however, that except as provided
      in this Section, Section 7 entitled "Indemnity and Contribution," and the
      last paragraph of Section 9 below, the Underwriters will pay all of their
      costs and expenses, including fees and disbursements of their counsel,
      stock transfer taxes payable on resale of any of the Shares by them, and
      any advertising expenses connected with any offers they may make.

            (g)   To not release any shares of Common Stock from any
      restrictions imposed upon such shares by the Lock-Up Agreements without
      the prior written consent of Morgan Stanley.

            (h)   That in connection with the Directed Share Program, the
      Company will ensure that the Directed Shares will be restricted to the
      extent required by the NASD or the NASD rules from sale, transfer,
      assignment, pledge or hypothecation for a period of three months following
      the date of the effectiveness of the Registration Statement.  Morgan
      Stanley will notify the Company as to which Participants will need to be
      so restricted.  The Company will direct the transfer agent to place
      stop-transfer restrictions upon such securities for such period of time.

            (i)   To comply with all applicable securities and other applicable
      laws, rules and regulations in each foreign jurisdiction in which the
      Directed Shares are offered in connection with the Directed Share Program.

            7.    INDEMNITY AND CONTRIBUTION.

            (a)   The Company agrees to indemnify and hold harmless each
      Underwriter and each person, if any, who controls any Underwriter within
      the meaning of either Section 15 of the Securities Act or Section 20 of
      the Securities Exchange Act of 1934, as amended (the "Exchange Act"), from
      and against any and all losses, claims, damages and liabilities
      (including, without limitation, any legal or other expenses reasonably
      incurred in connection with defending or investigating any such action or
      claim) caused by any untrue statement or alleged untrue statement of a
      material fact contained in the Registration Statement or any amendment
      thereof, any preliminary prospectus or the Prospectus (as amended or
      supplemented if the Company shall have furnished any amendments or
      supplements thereto) or caused by any omission or alleged omission to
      state therein a material fact required to be stated therein or necessary
      to make the statements therein not misleading; provided, however, that the
      Company will not be liable in any such case to the extent that such
      losses, claims, damages or liabilities are caused by any such untrue
      statement or omission or alleged untrue statement or omission based upon
      information relating to any Underwriter furnished to the Company in
      writing by such Underwriter through you expressly for use therein; and
      provided further that the foregoing indemnity agreement with respect to
      any preliminary prospectus shall not inure to the benefit of any
      Underwriter or any person controlling such Underwriter,

                                          11
<PAGE>

      from whom the person asserting any such losses, claims, damages or
      liabilities purchased Shares, if a copy of the Prospectus (as then
      supplemented if the Company shall have furnished any amendment or
      supplements thereto) was not sent or given by or on behalf of such
      Underwriter to such person, if required by law so to have been delivered,
      at or prior to the written confirmation of the sale of the Shares to such
      person, and if the Prospectus (as so amended or supplemented) would have
      cured the defect giving rise to such loss, claim, damage or liability,
      unless such failure is the result of non-compliance by the Company with
      Section 6(a) hereof.

            (b)   The Company agrees to indemnify and hold harmless Morgan
      Stanley and each person, if any, who controls Morgan Stanley within the
      meaning of either Section 15 of the Securities Act or Section 20 of the
      Exchange Act ("Morgan Stanley Entities"), from and against any and all
      losses, claims, damages and liabilities (including, without limitation,
      any legal or other expenses reasonably incurred in connection with
      defending or investigating any such action or claim) (i) caused by any
      untrue statement or alleged untrue statement of a material fact contained
      in the prospectus wrapper material attached to the Prospectus or any
      preliminary prospectus prepared by or with the consent of the Company for
      distribution in foreign jurisdictions in connection with the Directed
      Share Program, or caused by any omission or alleged omission to state
      therein a material fact required to be stated therein or necessary to make
      the statement therein, when considered in conjunction with the Prospectus
      or any applicable preliminary prospectus and in light of the circumstances
      in which they were made, not misleading; (ii) caused by the failure of any
      Participant to pay for and accept delivery of the shares which,
      immediately following the effectiveness of the Registration Statement,
      were subject to a properly confirmed agreement to purchase; or
      (iii) related to, arising out of, or in connection with the Directed Share
      Program, provided that, the Company shall not be responsible under this
      subparagraph (iii) for any losses, claim, damages or liabilities (or
      expenses relating thereto) that are finally judicially determined to have
      resulted from the bad faith or gross negligence of Morgan Stanley
      Entities.

            (c)   Each Underwriter agrees, severally and not jointly, to
      indemnify and hold harmless, the Company, its directors and officers who
      sign the Registration Statement, and each person, if any, who controls the
      Company within the meaning of either Section 15 of the Securities Act or
      Section 20 of the Exchange Act from and against any and all losses,
      claims, damages and liabilities (including, without limitation, any legal
      or other expenses reasonably incurred in connection with defending or
      investigating any such action or claim) caused by any untrue statement or
      alleged untrue statement of a material fact contained in the Registration
      Statement or any amendment thereof, any preliminary prospectus or the
      Prospectus (as amended or supplemented if the Company shall have furnished
      any amendments or supplements thereto), or caused by any omission or
      alleged omission to state therein a material fact required to be stated
      therein or necessary to make the statements therein not misleading, but
      only with reference to information relating to such Underwriter furnished
      to the Company in writing by or on behalf of such Underwriter through you
      expressly for use in the Registration Statement, any preliminary
      prospectus, the Prospectus or any amendments or supplements thereto.

            (d)   In case any proceeding (including any governmental
      investigation) shall be instituted involving any person in respect of
      which indemnity may be sought pursuant to paragraph (a), (b) or (c) of
      this Section 7, such person (the "indemnified party") shall promptly
      notify the person against whom such indemnity may be sought (the
      "indemnifying party") in writing and the indemnifying party, upon request
      of the indemnified party, shall retain counsel reasonably satisfactory to
      the indemnified party to represent the indemnified party and any others
      the indemnifying party may reasonably designate in such proceeding and
      shall pay the fees and disbursements of such counsel related to such
      proceeding. In any such proceeding, any indemnified party shall have the
      right to retain its own counsel, but the fees and expenses of such counsel
      shall be at the expense of such indemnified party unless (i) the
      indemnifying party and the indemnified party shall have mutually agreed to
      the retention of such counsel or (ii) the named parties to any such
      proceeding (including any impleaded parties) include both the indemnifying
      party and the indemnified party and representation of both parties by the
      same counsel would be inappropriate due to actual or potential differing
      interests between them. It is understood that the indemnifying party shall
      not, in respect of the legal expenses of any indemnified party in
      connection with any proceeding or related proceedings in the same
      jurisdiction, be liable for the fees and expenses of more than one
      separate firm (in addition to any local counsel) for (i) all Underwriters
      and all persons, if any, who control any Underwriter

                                          12
<PAGE>

      within the meaning of either Section 15 of the Securities Act or
      Section 20 of the Exchange Act, and (ii) the Company, its directors, its
      officers who sign the Registration Statement and each person, if any, who
      controls the Company within the meaning of either such Section, and that
      all such fees and expenses shall be reimbursed as they are incurred.  In
      the case of any such separate firm for the Underwriters and such control
      persons of the Underwriters, such firm shall be designated in writing by
      Morgan Stanley.  In the case of any such separate firm for the Company,
      and such directors, officers and control persons of the Company, such firm
      shall be designated in writing by the Company.  The indemnifying party
      shall not be liable for any settlement of any proceeding effected without
      its written consent, but if settled with such consent or if there be a
      final judgment for the plaintiff, the indemnifying party agrees to
      indemnify the indemnified party from and against any loss or liability by
      reason of such settlement or judgment.  Notwithstanding the foregoing
      sentence, if at any time an indemnified party shall have requested an
      indemnifying party to reimburse the indemnified party for fees and
      expenses of counsel as contemplated by the second and third sentences of
      this paragraph, the indemnifying party agrees that it shall be liable for
      any settlement of any proceeding effected without its written consent if
      (i) such settlement is entered into more than 60 days after receipt by
      such indemnifying party of the aforesaid request and (ii) such
      indemnifying party shall not have reimbursed the indemnified party in
      accordance with such request prior to the date of such settlement.  No
      indemnifying party shall, without the prior written consent of the
      indemnified party, effect any settlement of any pending or threatened
      proceeding in respect of which any indemnified party is or could have been
      a party and indemnity could have been sought hereunder by such indemnified
      party, unless such settlement includes an unconditional release of such
      indemnified party from all liability on claims that are the subject matter
      of such proceeding.  Notwithstanding anything contained herein to the
      contrary, if indemnity may be sought pursuant to Section 7(b) hereof in
      respect of such action or proceeding, then in addition to such separate
      firm for the indemnified parties, the indemnifying party shall be liable
      for the reasonable fees and expenses of not more than one separate firm
      (in addition to any local counsel) for Morgan Stanley for the defense of
      any losses, claims, damages and liabilities arising out of the Directed
      Share Program, and all persons, if any, who control Morgan Stanley within
      the meaning of either Section 15 of the Act or Section 20 of the Exchange
      Act provided that (i) the indemnifying party and Morgan Stanley shall have
      mutually agreed to the retention of such counsel or (ii) the
      representation of the indemnified parties and Morgan Stanley by the same
      counsel would be inappropriate due to actual or potential differing
      interests between them.

            (e)   To the extent the indemnification provided for in
      paragraph (a), (b) or (c) of this Section 7 is unavailable to an
      indemnified party or insufficient in respect of any losses, claims,
      damages or liabilities referred to therein, then each indemnifying party
      under such paragraph, in lieu of indemnifying such indemnified party
      thereunder, shall contribute to the amount paid or payable by such
      indemnified party as a result of such losses, claims, damages or
      liabilities (i) in such proportion as is appropriate to reflect the
      relative benefits received by the indemnifying party or parties on the one
      hand and the indemnified party or parties on the other hand from the
      offering of the Shares or (ii) if the allocation provided by clause (i)
      above is not permitted by applicable law, in such proportion as is
      appropriate to reflect not only the relative benefits referred to in
      clause (i) above but also the relative fault of the indemnifying party or
      parties on the one hand and of the indemnified party or parties on the
      other hand in connection with the statements or omissions that resulted in
      such losses, claims, damages or liabilities, as well as any other relevant
      equitable considerations.  The relative benefits received by the Company
      on the one hand and the Underwriters on the other hand in connection with
      the offering of the Shares shall be deemed to be in the same respective
      proportions as the net proceeds from the offering of the Shares (before
      deducting expenses) received by the Company and the total underwriting
      discounts and commissions received by the Underwriters, in each case as
      set forth in the table on the cover of the Prospectus, bear to the
      aggregate Public Offering Price of the Shares.  The relative fault of the
      Company and the Underwriters shall be determined by reference to, among
      other things, whether the untrue or alleged untrue statement of a material
      fact or the omission or alleged omission to state a material fact relates
      to information supplied by the Company or by the Underwriters and the
      parties' relative intent, knowledge, access to information and opportunity
      to correct or prevent such statement or omission.  The Underwriters'
      respective obligations to contribute pursuant to this Section 7 are
      several in proportion to the respective number of Shares they have
      purchased hereunder, and not joint.

                                          13
<PAGE>

            (f)   The Company and the Underwriters agree that it would not be
      just or equitable if contribution pursuant to this Section 7 were
      determined by PRO RATA allocation (even if the Underwriters were treated
      as one entity for such purpose) or by any other method of allocation that
      does not take account of the equitable considerations referred to in
      paragraph (e) of this Section 7.  The amount paid or payable by an
      indemnified party as a result of the losses, claims, damages and
      liabilities referred to in the immediately preceding paragraph shall be
      deemed to include, subject to the limitations set forth above, any legal
      or other expenses reasonably incurred by such indemnified party in
      connection with investigating or defending any such action or claim.
      Notwithstanding the provisions of this Section 7, no Underwriter shall be
      required to contribute any amount in excess of the amount by which the
      total price at which the Shares underwritten by it and distributed to the
      public were offered to the public exceeds the amount of any damages that
      such Underwriter has otherwise been required to pay by reason of such
      untrue or alleged untrue statement or omission or alleged omission.  No
      person guilty of fraudulent misrepresentation (within the meaning of
      Section 11(f) of the Securities Act) shall be entitled to contribution
      from any person who was not guilty of such fraudulent misrepresentation.
      The remedies provided for in this Section 7 are not exclusive and shall
      not limit any rights or remedies which may otherwise be available to any
      indemnified party at law or in equity.

            (g)   The indemnity and contribution provisions contained in this
      Section 7 and the representations, warranties and other statements of the
      Company contained in this Agreement shall remain operative and in full
      force and effect regardless of (i) any termination of this Agreement,
      (ii) any investigation made by or on behalf of any Underwriter or any
      person controlling any Underwriter, or the Company, its officers or
      directors or any person controlling the Company and (iii) acceptance of
      and payment for any of the Shares.

            8.    TERMINATION.  This Agreement shall be subject to termination
by notice given by you to the Company, if (a) after the execution and delivery
of this Agreement and prior to the Closing Date (i) trading generally shall have
been suspended or materially limited on or by, as the case may be, any of the
New York Stock Exchange, the American Stock Exchange, the National Association
of Securities Dealers, Inc., the Chicago Board of Options Exchange, the Chicago
Mercantile Exchange or the Chicago Board of Trade, (ii) trading of any
securities of the Company shall have been suspended on any exchange or in any
over-the-counter market, (iii) a general moratorium on commercial banking
activities in New York shall have been declared by either Federal or New York
State authorities or (iv) there shall have occurred any outbreak or escalation
of hostilities or any change in financial markets or any calamity or crisis
that, in your judgment, is material and adverse and (b) in the case of any of
the events specified in clauses (a)(i) through (iv), such event, singly or
together with any other such event, makes it, in your judgment, impracticable to
market the Shares on the terms and in the manner contemplated in the Prospectus.

            9.    EFFECTIVENESS: DEFAULTING UNDERWRITERS.  This Agreement shall
become effective upon the execution and delivery hereof by the parties hereto.

            If, on the Closing Date or the Option Closing Date, as the case may
be, any one or more of the Underwriters shall fail or refuse to purchase Shares
that it has or they have agreed to purchase hereunder on such date, and the
aggregate number of Shares which such defaulting Underwriter or Underwriters
agreed but failed or refused to purchase is not more than one-tenth of the
aggregate number of the Shares to be purchased on such date, the other
Underwriters shall be obligated severally in the proportions that the number of
Firm Shares set forth opposite their respective names in Schedule I bears to the
aggregate number of Firm Shares set forth opposite the names of all such
non-defaulting Underwriters, or in such other proportions as you may specify, to
purchase the Shares which such defaulting Underwriter or Underwriters agreed but
failed or refused to purchase on such date; PROVIDED that in no event shall the
number of Shares that any Underwriter has agreed to purchase pursuant to this
Agreement be increased pursuant to this Section 9 by an amount in excess of
one-ninth of such number of Shares without the written consent of such
Underwriter.  If, on the Closing Date, any Underwriter or Underwriters shall
fail or refuse to purchase Firm Shares and the aggregate number of Firm Shares
with respect to which such default occurs is more than one-tenth of the
aggregate number of Firm Shares to be purchased, and arrangements satisfactory
to you and the Company for the purchase of such Firm Shares are not made within
36 hours after such default, this Agreement shall terminate without liability on
the part of any non-defaulting Underwriter or the Company.  In any such case
either you or the Company shall have the right to postpone the Closing Date, but
in no event for longer than seven days, in order that the required changes, if
any, in the Registration Statement and in the

                                          14
<PAGE>

Prospectus or in any other documents or arrangements may be effected.  If, on
the Option Closing Date, any Underwriter or Underwriters shall fail or refuse to
purchase Additional Shares and the aggregate number of Additional Shares with
respect to which such default occurs is more than one-tenth of the aggregate
number of Additional Shares to be purchased, the non-defaulting Underwriters
shall have the option to (i) terminate their obligation hereunder to purchase
Additional Shares or (ii) purchase not less than the number of Additional Shares
that such non-defaulting Underwriters would have been obligated to purchase in
the absence of such default.  Any action taken under this paragraph shall not
relieve any defaulting Underwriter from liability in respect of any default of
such Underwriter under this Agreement.

            If this Agreement shall be terminated by the Underwriters, or any of
them, because of any failure or refusal on the part of the Company to comply
with the terms or to fulfill any of the conditions placed upon it in this
Agreement, or if for any reason the Company shall be unable to perform its
obligations under this Agreement that are within its control, the Company will
reimburse the Underwriters or such Underwriters as have so terminated this
Agreement with respect to themselves, severally, for all out-of-pocket expenses
(including the fees and disbursements of their counsel) reasonably incurred by
such Underwriters in connection with this Agreement or the offering contemplated
hereunder.

            10.   COUNTERPARTS.  This Agreement may be signed in two or more
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

            11.   APPLICABLE LAW.  This Agreement shall be governed by and
construed in accordance with the internal laws of the State of New York.

            12.   HEADINGS.  The headings of the sections of this Agreement have
been inserted for convenience of reference only and shall not be deemed a part
of this Agreement.

                                          15
<PAGE>


                                          Very truly yours,

                                          INTUITIVE SURGICAL, INC.

                                          By:
                                             -----------------------------------
                                             Name:  Lonnie M. Smith
                                             Title:  President and Chief
                                                     Executive Officer

Accepted as of the date hereof:

MORGAN STANLEY & CO. INCORPORATED
BEAR, STEARNS & CO. INC.
BT ALEX. BROWN INCORPORATED

Acting severally on behalf of themselves
      and the several Underwriters
      named in Schedule I hereto.

By:   Morgan Stanley & Co. Incorporated

By:
    -----------------------------------------
            Name:
            Title:



<PAGE>

                                      SCHEDULE I

                                                                    Number of
                                                                   Firm Shares
UNDERWRITER                                                      TO BE PURCHASED

Morgan Stanley & Co. Incorporated
Bear, Stearns & Co. Inc.
BT Alex. Brown Incorporated


                  Total:


