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                                                                   EXHIBIT 10.24


                          CHANGE OF CONTROL AGREEMENT

          This Change of Control Agreement (the "Agreement") is made and entered
into effective as of May 6, 1997, by and between  (the "Employee") and
KeraVision, Inc., a Delaware corporation (the "Company").


                                    RECITALS

          A.   It is expected that another company or other entity may from time
to time consider the possibility of acquiring the Company or that a change in
control may otherwise occur, with or without the approval of the Company's Board
of Directors (the "Board").  The Board recognizes that such consideration can be
a distraction to the Employee, a corporate officer of the Company, and can cause
the Employee to consider alternative employment opportunities.  The Board has
determined that it is in the best interests of the Company and its stockholders
to assure that the Company will have the continued dedication and objectivity of
the Employee, notwithstanding the possibility, threat or occurrence of a Change
of Control (as defined below) of the Company.

          B.   The Board believes that it is in the best interests of the
Company and its stockholders to provide the Employee with an incentive to
continue his or her employment with the Company.

          C.   The Board believes that it is imperative to provide the Employee
with certain benefits upon a Change of Control and, under certain circumstances,
upon termination of the Employee's employment in connection with a Change of
Control, which benefits are intended to provide the Employee with financial
security and provide sufficient income and encouragement to the Employee to
remain with the Company notwithstanding the possibility of a Change of Control.

          D.   To accomplish the foregoing objectives, the Board of Directors
has directed the Company, upon execution of this Agreement by the Employee, to
agree to the terms provided in this Agreement.

          E.   Certain capitalized terms used in the Agreement are defined in
Section 4 below.

          In consideration of the mutual covenants contained in this Agreement,
and in consideration of the continuing employment of Employee by the Company,
the parties agree as follows:

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          1.   At-Will Employment.  The Company and the Employee acknowledge
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that the Employee's employment is and shall continue to be at-will, as defined
under applicable law. If the Employee's employment terminates for any reason,
including (without limitation) any termination prior to a Change of Control, the
Employee shall not be entitled to any payments or benefits, other than as
provided by this Agreement, or as may otherwise be available in accordance with
the terms of the Company's established employee plans and written policies at
the time of termination. The terms of this Agreement shall terminate upon the
earlier of (i) the date on which Employee ceases to be employed as a corporate
officer of the Company, other than as a result of an involuntary termination by
the Company without Cause (ii) the date that all obligations of the parties
hereunder have been satisfied, or (iii) two (2) years after a Change of Control.
A termination of the terms of this Agreement pursuant to the preceding sentence
shall be effective for all purposes, except that such termination shall not
affect the payment or provision of compensation or benefits on account of a
termination of employment occurring prior to the termination of the terms of
this Agreement.

          2.   Stock Options.
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               (a) Hostile Takeover.  Subject to Sections 5 and 6 below, in
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the event of a Hostile Takeover and regardless of whether the Employee's
employment with the Company is terminated in connection with the Hostile
Takeover, each stock option granted for the Company's securities (the "Option")
held by the Employee shall become fully vested and immediately exercisable on
the effective date of the transaction and shall be exercisable to the extent so
vested in accordance with the provisions of the Option Agreement and Plan
pursuant to which such Option was granted.

               (b) Change of Control.  Subject to Sections 5 and 6 below, in the
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event of a Change of Control and regardless of whether the Employee's employment
with the Company is terminated in connection with the Change of Control, each
Option held by the Employee shall become vested on the effective date of the
transaction as to fifty percent (50%) of the Option shares that have not
otherwise vested as of such date.  The Option shares that remain unvested as of
the effective date of the transaction shall thereafter vest at the same rate
(that is, the same number of shares shall vest during each vesting period) that
was in effect prior to the Change of Control, and shall accordingly vest over a
period that is one-half of the total vesting period that would otherwise be then
remaining under the terms of the Option Agreement pursuant to which each such
Option was granted.

          3.   Change of Control.
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               (a) Termination Following A Change of Control.  Subject to
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Sections 5 and 6 below, if the Employee's employment with the Company is
terminated at any time within two (2) years after a Change of Control, then the
Employee shall be entitled to receive severance benefits as follows:

                   (i) Voluntary Resignation.  If the Employee voluntarily
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resigns from the Company (other than as an Involuntary Termination (as defined
below) or if the Company terminates the Employee's employment for Cause (as
defined below)), then the

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Employee shall not be entitled to receive severance payments. The Employee's
benefits will be terminated under the Company's then existing benefit plans and
policies in accordance with such plans and policies in effect on the date of
termination or as otherwise determined by the Board of Directors of the Company.

                   (ii) Involuntary Termination.  If the Employee's employment
                        -----------------------
is terminated as a result of an Involuntary Termination other than for Cause,
the Employee shall be entitled to receive the following benefits: (i) severance
payments during the period from the date of the Employee's termination until the
date 12 months after the effective date of the termination (the "Severance
Period") equal to the salary which the Employee was receiving at the time of
such termination, which payments shall be paid during the Severance Period in
accordance with the Company's standard payroll practices; (ii) monthly severance
payments during the Severance Period equal to 1/12th of the Employee's "target
bonus" (as defined below) for the fiscal year in which the termination occurs
(or for the prior fiscal year if a target bonus has not yet been determined for
the fiscal year in which the termination occurs); (iii) continuation of all
health and life insurance benefits through the end of the Severance Period
substantially identical to those to which the Employee was entitled immediately
prior to the termination, or to those being offered to officers of the Company,
or a successor corporation, if the Company's benefit programs are changed during
the Severance Period; (iv) full and immediate vesting of each unvested Option
held by the Employee on the date of termination so that each such option shall
be exercisable in full on the termination date in accordance with the provisions
of the Option Agreement and Plan pursuant to which such option was granted; and
(v) outplacement services with a total value not to exceed $15,000. For purposes
of this Agreement, the term "target bonus" shall mean the Employee's base salary
in effect on the termination date multiplied by that percentage of such base
salary that is prescribed by the Company under its Executive Bonus Program as
the percentage of such base salary payable to the Employee as a bonus if the
Company pays bonuses at one-hundred percent (100%) of its operating plan.

                   (iii)  Involuntary Termination for Cause.  If the
                          ---------------------------------
Employee's employment is terminated for Cause, then the Employee shall not be
entitled to receive severance payments.  The Employee's benefits will be
terminated under the Company's then existing benefit plans and policies in
accordance with such plans and policies in effect on the date of termination.

          (b) Termination Apart from A Change of Control.  In the event the
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Employee's employment terminates for any reason, either prior to the occurrence
of a Change of Control or after the two year period following the effective date
of a Change of Control, then the Employee shall not be entitled to receive any
severance payments under this Agreement.  The Employee's benefits will be
terminated under the terms of the Company's then existing benefit plans and
policies in accordance with such plans and policies in effect on the date of
termination or as otherwise determined by the Board of Directors of the Company.

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           4.   Definition of Terms.  The following terms referred to
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in this Agreement shall have the following meanings:

                (a) Change of Control.  "Change of Control" shall mean the
                    -----------------
occurrence of any of the following events:

                    (i) Ownership.  Any "Person" (as such term is used in
                        ---------
Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended) is
or becomes the "Beneficial Owner" (as defined in Rule 13d-3 under said Act),
directly or indirectly, of securities of the Company representing twenty percent
(20%) or more of the total voting power represented by the Company's then
outstanding voting securities without the approval of the Board of Directors of
the Company; or

                    (ii) Merger/Sale of Assets.  A merger or consolidation of
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the Company whether or not approved by the Board of Directors of the Company,
other than a merger or consolidation which would result in the voting securities
of the Company outstanding immediately prior thereto continuing to represent
(either by remaining outstanding or by being converted into voting securities of
the surviving entity) at least fifty percent (50%) of the total voting power
represented by the voting securities of the Company or such surviving entity
outstanding immediately after such merger or consolidation, or the stockholders
of the Company approve a plan of complete liquidation of the Company or an
agreement for the sale or disposition by the Company of all or substantially all
of the Company's assets.

                     (iii)  Change in Board Composition.  A change in
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the composition of the Board of Directors of the Company, as a result of which
fewer than a majority of the directors are Incumbent Directors.  "Incumbent
Directors" shall mean directors who either (A) are directors of the Company as
of May 6, 1997 or (B) are elected, or nominated for election, to the Board of
Directors of the Company with the affirmative votes of at least a majority of
the Incumbent Directors at the time of such election or nomination (but shall
not include an individual whose election or nomination is in connection with an
actual or threatened proxy contest relating to the election of directors to the
Company).

                (b) Cause.  "Cause" shall mean (i) gross negligence or willful
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misconduct in the performance of the Employee's duties to the Company where such
gross negligence or willful misconduct has resulted or is likely to result in
substantial and material damage to the Company or its subsidiaries,
(ii) repeated unexplained or unjustified absence from the Company, (iii) a
material and willful violation of any federal or state law; (iv) commission of
any act of fraud with respect to the Company; or (v) conviction of a felony or a
crime involving moral turpitude causing material harm to the standing and
reputation of the Company, in each case as determined in good faith by the Board
of Directors of the Company.

                (c) Hostile Takeover.  "Hostile Takeover" shall mean a
                    ----------------
transaction or series of transactions that results in any Person becoming the
Beneficial Owner, directly or

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indirectly, of securities of the Company representing more than 50% of the total
voting power represented by the Company's then outstanding voting securities
without the approval of the Board of Directors of the Company.

                (d) Involuntary Termination.  "Involuntary Termination" shall
                    -----------------------
include any termination by the Company other than for Cause and the Employee's
voluntary termination, upon 30 days prior written notice to the Company,
following (i) a material reduction or change in job duties, responsibilities and
requirements inconsistent with the Employee's position with the Company and the
Employee's prior duties, responsibilities and requirements; (ii) any reduction
of the Employee's base compensation (other than in connection with a general
decrease in base salaries for most similarly situated employees of the successor
corporation); or (iii) the Employee's refusal to relocate to a location more
than 50 miles from the Company's current location.

            5.  Limitation on Payments.  In the event that the severance and
                ----------------------
other benefits provided for in this Agreement to the Employee (i) constitute
"parachute payments" within the meaning of Section 280G of the Internal Revenue
Code of 1986, as amended (the "Code") and (ii) but for this Section, would be
subject to the excise tax imposed by Section 4999 of the Code, then the
Employee's benefits under Sections 2 and 3(a)(ii) shall be payable either:

                (a)  in full, or

                (b)  as to such lesser amount which would result in no
portion of such severance benefits being subject to excise tax under
Section 4999 of the Code, whichever of the foregoing amounts, taking into
account the applicable federal, state and local income taxes and the excise tax
imposed by Section 4999, results in the receipt by the Employee on an after-tax
basis, of the greatest amount of benefits under Sections 2 and 3(a)(ii),
notwithstanding that all or some portion of such benefits may be taxable under
Section 4999 of the Code. Unless the Company and the Employee otherwise agree in
writing, any determination required under this Section 5 shall be made in
writing by the Company's independent public accountants (the "Accountants"),
whose determination shall be conclusive and binding upon the Employee and the
Company for all purposes. For purposes of making the calculations required by
this Section 5, the Accountants may make reasonable assumptions and
approximations concerning applicable taxes and may rely on reasonable, good
faith interpretations concerning the application of Section 280G and 4999 of the
Code. The Company and the Employee shall furnish to the Accountants such
information and documents as the Accountants may reasonably request in order to
make a determination under this Section. The Company shall bear all costs the
Accountants may reasonably incur in connection with any calculations
contemplated by this Section 5.

            6.  Certain Business Combinations.  In the event it is
                -----------------------------
determined by the Board, upon consultation with Company management and the
Company's independent auditors, that the enforcement of any Section of this
Agreement, including, but not limited to, Section 2 hereof, which allows for the
acceleration of vesting of Option shares upon the

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effective date of a Hostile Takeover or a Change of Control, would preclude
accounting for any proposed business combination of the Company involving a
Hostile Takeover or a Change of Control as a pooling of interests, and the Board
otherwise desires to approve such a proposed business transaction which requires
as a condition to the closing of such transaction that it be accounted for as a
pooling of interests, then any such Section of this Agreement shall be null and
void. For purposes of this Section 6, the Board's determination shall require
the unanimous approval of the non-employee Board members.

            7.  Successors.  Any successor to the Company (whether direct or
                ----------
indirect and whether by purchase, lease, merger, consolidation, liquidation or
otherwise) to all or substantially all of the Company's business and/or assets
shall assume the obligations under this Agreement and agree expressly to perform
the obligations under this Agreement in the same manner and to the same extent
as the Company would be required to perform such obligations in the absence of a
succession.  The terms of this Agreement and all of the Employee's rights
hereunder shall inure to the benefit of, and be enforceable by, the Employee's
personal or legal representatives, executors, administrators, successors, heirs,
distributees, devisees and legatees.

            8.  Notice.  Notices and all other communications contemplated
                ------
by this Agreement shall be in writing and shall be deemed to have been duly
given when personally delivered or when mailed by U.S. registered or certified
mail, return receipt requested and postage prepaid.  Mailed notices to the
Employee shall be addressed to the Employee at the home address which the
Employee most recently communicated to the Company in writing.  In the case of
the Company, mailed notices shall be addressed to its corporate headquarters,
and all notices shall be directed to the attention of its Secretary.

            9.  Miscellaneous Provisions.
                ------------------------

                (a) No Duty to Mitigate.  The Employee shall not be required to
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mitigate the amount of any payment contemplated by this Agreement (whether by
seeking new employment or in any other manner), nor, except as otherwise
provided in this Agreement, shall any such payment be reduced by any earnings
that the Employee may receive from any other source.

                (b) Waiver.  No provision of this Agreement shall be modified,
                    ------
waived or discharged unless the modification, waiver or discharge is agreed to
in writing and signed by the Employee and by an authorized officer of the
Company (other than the Employee). No waiver by either party of any breach of,
or of compliance with, any condition or provision of this Agreement by the other
party shall be considered a waiver of any other condition or provision or of the
same condition or provision at another time.

                (c) Whole Agreement.  No agreements, representations or
                    ---------------
understandings (whether oral or written and whether express or implied) which
are not expressly set forth in this Agreement have been made or entered into by
either party with respect to the subject matter hereof. This Agreement
supersedes any agreement of the same title and concerning similar subject matter
dated prior to the date of this Agreement, and by

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execution of this Agreement both parties agree that any such predecessor
agreement shall be deemed null and void.

                (d) Choice of Law.  The validity, interpretation, construction
                    -------------
and performance of this Agreement shall be governed by the laws of the State of
California without reference to conflict of laws provisions.

                (e) Severability.  If any term or provision of this Agreement
                    ------------
or the application thereof to any circumstance shall, in any jurisdiction and to
any extent, be invalid or unenforceable, such term or provision shall be
ineffective as to such jurisdiction to the extent of such invalidity or
unenforceability without invalidating or rendering unenforceable the remaining
terms and provisions of this Agreement or the application of such terms and
provisions to circumstances other than those as to which it is held invalid or
unenforceable, and a suitable and equitable term or provision shall be
substituted therefor to carry out, insofar as may be valid and enforceable, the
intent and purpose of the invalid or unenforceable term or provision.

                (f) Arbitration.  Any dispute or controversy arising under or in
                    -----------
connection with this Agreement may be settled at the option of either party by
binding arbitration in the County of Contra Costa, California, in accordance
with the rules of the American Arbitration Association then in effect.  Judgment
may be entered on the arbitrator's  award in any court having jurisdiction.
Punitive damages shall not be awarded.

                (g) Legal Fees and Expenses.  The parties shall each bear
                    -----------------------
their own expenses, legal fees and other fees incurred in connection with this
Agreement.

                (h) No Assignment of Benefits.  The rights of any person to
                    -------------------------
payments or benefits under this Agreement shall not be made subject to option or
assignment, either by voluntary or involuntary assignment or by operation of
law, including (without limitation) bankruptcy, garnishment, attachment or other
creditor's process, and any action in violation of this subsection (h) shall be
void.

                (i) Employment Taxes.  All payments made pursuant to this
                    ----------------
Agreement will be subject to withholding of applicable income and employment
taxes.

                (j) Assignment by Company.  The Company may assign its rights
                    ---------------------
under this Agreement to an affiliate, and an affiliate may assign its rights
under this Agreement to another affiliate of the Company or to the Company;
provided, however, that no assignment shall be made if the net worth of the
assignee is less than the net worth of the Company at the time of assignment. In
the case of any such assignment, the term "Company" when used in a section of
this Agreement shall mean the corporation that actually employs the Employee.

                (k) Counterparts.  This Agreement may be executed in
                    ------------
counterparts, each of which shall be deemed an original, but all of which
together will constitute one and the same instrument.

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          IN WITNESS WHEREOF, each of the parties has executed this Agreement,
in the case of the Company by its duly authorized officer, as of the day and
year first above written.



KERAVISION, INC.


By:
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Title:
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