EXHIBIT 4.3

                                CATALYTICA, INC.

                           1995 DIRECTOR OPTION PLAN

                         (AS AMENDED THROUGH JUNE 1997)


     1.   Purposes of the Plan.  The purposes of this 1995 Director Option Plan
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are to attract and retain the best available personnel for service as Outside
Directors (as defined herein) of the Company, to provide additional incentive to
the Outside Directors of the Company to serve as Directors, and to encourage
their continued service on the Board.

          All options granted hereunder shall be nonstatutory stock options.

     2.   Definitions.  As used herein, the following definitions shall apply:
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          (a)  "Board" means the Board of Directors of the Company.
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          (b)  "Code" means the Internal Revenue Code of 1986, as amended.
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          (c)  "Common Stock" means the Common Stock of the Company.
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          (d)  "Company" means Catalytica, Inc. a Delaware corporation.
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          (e)  "Director" means a member of the Board.
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          (f)  "Employee" means any person, including officers and Directors,
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employed by the Company or any Parent or Subsidiary of the Company.  The payment
of a Director's fee by the Company shall not be sufficient in and of itself to
constitute "employment" by the Company.

          (g)  "Exchange Act" means the Securities Exchange Act of 1934, as
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amended.

          (h)  "Fair Market Value" means, as of any date, the value of Common
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Stock determined as follows:

               (i)     If the Common Stock is listed on any established stock
exchange or a national market system, including without limitation the Nasdaq
National Market of the National Association of Securities Dealers, Inc.
Automated Quotation ("NASDAQ") System, the Fair Market Value of a Share of
Common Stock shall be the closing sales price for such stock (or the closing
bid, if no sales were reported) as quoted on such system or exchange (or the
exchange with the greatest volume of trading in Common Stock) on the date of
determination, as reported in The Wall Street Journal or such other source as
the Board deems reliable;

 
               (ii)    If the Common Stock is quoted on the NASDAQ System (but 
not on the National Market thereof) or regularly quoted by a recognized
securities dealer but selling prices are not reported, the Fair Market Value of
a Share of Common Stock shall be the mean between the high bid and low asked
prices for the Common Stock on the date of determination, as reported in The
Wall Street Journal or such other source as the Board deems reliable, or;

               (iii)   In the absence of an established market for the Common
Stock, the Fair Market Value thereof shall be determined in good faith by the
Board.

          (i)  "Inside Director" means a Director who is an Employee.
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          (j)  "Option" means a stock option granted pursuant to the Plan.
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          (k)  "Optioned Stock" means the Common Stock subject to an Option.
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          (l)  "Optionee"  means a Director who holds an Option.
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          (m)  "Outside Director" means a Director who is not an Employee and is
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neither affiliated with or nominated to be a Director by a stockholder that owns
five percent (5%) or more of the outstanding capital stock of the Company.

          (n)  "Parent" means a "parent corporation," whether now or hereafter
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existing, as defined in Section 424(e) of the Code.

          (o)  "Plan" means this 1995 Director Option Plan.
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          (p)  "Share" means a share of the Common Stock, as adjusted in
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accordance with Section 10 of the Plan.

          (q)  "Subsidiary" means a "subsidiary corporation," whether now or
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hereafter existing, as defined in Section 424(f) of the Internal Revenue Code of
1986.

     3.   Stock Subject to the Plan.  Subject to the provisions of Section 10 of
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the Plan, the maximum aggregate number of Shares which may be optioned and sold
under the Plan is 200,000 Shares of Common Stock (the "Pool").  The Shares may
be authorized, but unissued, or reacquired Common Stock.

          If an Option expires or becomes unexercisable without having been
exercised in full, the unpurchased Shares which were subject thereto shall
become available for future grant or sale under the Plan (unless the Plan has
terminated).  Shares that have actually been issued under the Plan shall not be
returned to the Plan and shall not become available for future distribution
under the Plan.

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     4.   Administration and Grants of Options under the Plan.
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          (a)  Procedure for Grants.  The provisions set forth in this Section
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4(a) shall not be amended more than once every six months, other than to comport
with changes in the Code, the Employee Retirement Income Security Act of 1974,
as amended, or the rules thereunder.  All grants of Options to Outside Directors
under this Plan shall be automatic and nondiscretionary and shall be made
strictly in accordance with the following provisions:

               (i)    No person shall have any discretion to select which 
Outside Directors shall be granted Options or to determine the number of Shares
to be covered by Options granted to Outside Directors.

               (ii)   Each Outside Director shall be automatically granted an
Option (the "First Option") to purchase the number of Shares provided for in
Section 4(a)(iii) below (the "First Option") on the date on which the later of
the following events occurs:  (A) the effective date of this Plan, as determined
in accordance with Section 6 hereof, or (B) the date on which such person first
becomes an Outside Director, whether through election by the stockholders of the
Company or appointment by the Board to fill a vacancy; provided, however, that
an Inside Director who ceases to be an Inside Director but who remains a
Director shall not receive a First Option.

               (iii)  The number of Shares covered by First Options shall be 
as follows:

                      (A) A First Option granted to Utz Felcht ("Felcht") 
shall be an Option to purchase 15,000 Shares.

                      (B) A First Option granted to Richard Fleming 
("Fleming") shall be an Option to purchase 7,000 Shares.

                      (C) A First Option granted to any Outside Director 
other than Felcht and Fleming shall be an Option to purchase 20,000 Shares.

               (iv)   Each Outside Director shall be automatically granted an
Option to purchase 4,000 Shares (a "Subsequent Option") on the first day of each
fiscal year of the Company provided that he or she is then an Outside Director
and that, as of such date, he or she shall have served as an Outside Director
for the preceding six (6) months.

               (v)    Notwithstanding the provisions of Sections 4(a)(ii), 
(iii) and (iv) above, any exercise of an Option granted before the Company has
obtained stockholder approval of the Plan in accordance with Section 16 hereof
shall be conditioned upon obtaining such stockholder approval of the Plan in
accordance with Section 16 hereof.

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               (vi)   The terms of a First Option granted hereunder shall be as
follows:

                      (A) the term of the First Option shall be ten (10) years.

                      (B) the First Option shall be exercisable only while the 
Outside Director remains a Director of the Company, except as set forth in
Sections 8 and 10 hereof.

                      (C) the exercise price per Share shall be 100% of the 
Fair Market Value per Share on the date of grant of the First Option. In the
event that the date of grant of the First Option is not a trading day, the
exercise price per Share shall be the Fair Market Value on the next trading day
immediately following the date of grant of the First Option.

                      (D) subject to Section 10 hereof, the First Option shall 
become exercisable as to one-sixth (1/6th) of the Shares subject to the First
Option six (6) months after its date of grant, and as to one thirty-sixth
(1/36th) of the Shares subject to the First Option at the end of each month
thereafter, provided that the Optionee continues to serve as a Director on such
dates.

               (vii)  The terms of a Subsequent Option granted hereunder shall 
be as follows:

                      (A) the term of the Subsequent Option shall be ten (10)
years.

                      (B) the Subsequent Option shall be exercisable only while 
the Outside Director remains a Director of the Company, except as set forth in
Sections 8 and 10 hereof.

                      (C) the exercise price per Share shall be 100% of the 
Fair Market Value per Share on the date of grant of the Subsequent Option. In
the event that the date of grant of the Subsequent Option is not a trading day,
the exercise price per Share shall be the Fair Market Value on the next trading
day immediately following the date of grant of the Subsequent Option.

                      (D) subject to Section 10 hereof, the Subsequent Option 
shall become exercisable as to one-twelfth (1/12th) of the Shares subject to the
Subsequent Option at the end of each month after its date of grant, provided
that the Optionee continues to serve as a Director on such dates.

               (viii) In the event that any Option granted under the Plan would
cause the number of Shares subject to outstanding Options plus the number of
Shares previously purchased under Options to exceed the Pool, then the remaining
Shares available for Option grant shall be granted under Options to the Outside
Directors on a pro rata basis.  No further grants shall be made until such time,
if any, as additional Shares become available for grant under the Plan through
action of the Board or the stockholders to increase the number of Shares which
may be issued under the Plan or through cancellation or expiration of Options
previously granted hereunder.

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     5.   Eligibility.  Options may be granted only to Outside Directors.  All
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Options shall be automatically granted in accordance with the terms set forth in
Section 4 hereof.

          The Plan shall not confer upon any Optionee any right with respect to
continuation of service as a Director or nomination to serve as a Director, nor
shall it interfere in any way with any rights which the Director or the Company
may have to terminate the Director's relationship with the Company at any time.

     7.   Term of Plan.  The Plan shall become effective upon the earlier to
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occur of its adoption by the Board or its approval by the stockholders of the
Company as described in Section 16 of the Plan.  It shall continue in effect for
a term of ten (10) years unless sooner terminated under Section 11 of the Plan.

     8.   Form of Consideration.  The consideration to be paid for the Shares to
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be issued upon exercise of an Option, including the method of payment, shall
consist of (i) cash, (ii) check, (iii) other shares which (x) in the case of
Shares acquired upon exercise of an Option, have been owned by the Optionee for
more than six (6) months on the date of surrender, and (y) have a Fair Market
Value on the date of surrender equal to the aggregate exercise price of the
Shares as to which said Option shall be exercised, (iv) delivery of a properly
executed exercise notice together with such other documentation as the Company
and the broker, if applicable, shall require to effect an exercise of the Option
and delivery to the Company of the sale or loan proceeds required to pay the
exercise price, or (v) any combination of the foregoing methods of payment.

     9.   Exercise of Option.
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          (a)  Procedure for Exercise; Rights as a Stockholder. Any Option
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granted hereunder shall be exercisable at such times as are set forth in Section
4 hereof.

          An Option may not be exercised for a fraction of a Share.

          An Option shall be deemed to be exercised when written notice of such
exercise has been given to the Company in accordance with the terms of the
Option by the person entitled to exercise the Option and full payment for the
Shares with respect to which the Option is exercised has been received by the
Company.  Full payment may consist of any consideration and method of payment
allowable under Section 7 of the Plan.  Until the issuance (as evidenced by the
appropriate entry on the books of the Company or of a duly authorized transfer
agent of the Company) of the stock certificate evidencing such Shares, no right
to vote or receive dividends or any other rights as a stockholder shall exist
with respect to the Optioned Stock, notwithstanding the exercise of the Option.
A share certificate for the number of Shares so acquired shall be issued to the
Optionee as soon as practicable after exercise of the Option. No adjustment
shall be made for a dividend or other right for which the record date is prior
to the date the stock certificate is issued, except as provided in Section 10 of
the Plan.

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          Exercise of an Option in any manner shall result in a decrease in the
number of Shares which thereafter may be available, both for purposes of the
Plan and for issuance under the Option, by the number of Shares as to which the
Option is exercised.

          (b)  Rule 16b-3.  Options granted to Outside Directors must comply
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with the applicable provisions of Rule 16b-3 promulgated under the Exchange Act
or any successor thereto and shall contain such additional conditions or
restrictions as may be required thereunder to qualify Plan transactions, and
other transactions by Outside Directors that otherwise could be matched with
Plan transactions, for the maximum exemption from Section 16 of the Exchange
Act.

          (c)  Termination of Continuous Status as a Director.  Subject to
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Section 10 hereof, in the event an Optionee's status as a Director terminates
(other than upon the Optionee's death or total and permanent disability (as
defined in Section 22(e)(3) of the Code)), the Optionee may exercise his or her
Option, but only within three (3) months following the date of such termination,
and only to the extent that the Optionee is entitled to exercise it on the date
of such termination (but in no event later than the expiration of its ten (10)
year term).  To the extent that the Optionee is not entitled to exercise an
Option on the date of such termination, and to the extent that the Optionee does
not exercise such Option (to the extent otherwise so entitled) within the time
specified herein, the Option shall terminate.

          (d)  Disability of Optionee.  In the event Optionee's status as a
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Director terminates as a result of total and permanent disability (as defined in
Section 22(e)(3) of the Code), the Optionee may exercise his or her Option, but
only within twelve (12) months following the date of such termination, and only
to the extent that the Optionee is entitled to exercise it on the date of such
termination (but in no event later than the expiration of its ten (10) year
term).  To the extent that the Optionee is not entitled to exercise an Option on
the date of termination, or if he or she does not exercise such Option (to the
extent otherwise so entitled) within the time specified herein, the Option shall
terminate.

          (e)  Death of Optionee.  In the event of an Optionee's death, the
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Optionee's estate or a person who acquired the right to exercise the Option by
bequest or inheritance may exercise the Option, but only within twelve (12)
months following the date of death, and only to the extent that the Optionee is
entitled to exercise it on the date of death (but in no event later than the
expiration of its ten (10) year term).  To the extent that the Optionee is not
entitled to exercise an Option on the date of death, and to the extent that the
Optionee's estate or a person who acquired the right to exercise such Option
does not exercise such Option (to the extent otherwise so entitled) within the
time specified herein, the Option shall terminate.

     9.   Non-Transferability of Options.  The Option may not be sold, pledged,
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assigned, hypothecated, transferred, or disposed of in any manner other than by
will or by the laws of descent or distribution and may be exercised, during the
lifetime of the Optionee, only by the Optionee.

     10.  Adjustments Upon Changes in Capitalization, Dissolution or Liquidation
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          or Change of Control.
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          (a)  Changes in Capitalization.  In the event that the stock of the
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Company is changed by reason of any stock split, reverse stock split,
recapitalization, or other change in the capital structure of the Company, or
converted into or exchanged for other securities as a result of any merger,
consolidation or reorganization, or in the event that the outstanding number of
shares of stock of the Company is increased through payment of a stock dividend,
appropriate proportionate adjustments shall be made in the number and class of
shares of stock subject to the Plan, the number and class of shares subject to
any Option outstanding under the Plan, and the exercise price of any such
outstanding Option; provided, however, that the Company shall not be required to
issue fractional shares as a result of any such adjustment.  Any such adjustment
shall be made upon approval by the Board, whose determination shall be
conclusive.  If there is any other change in the number or type of the
outstanding shares of stock of the Company, or of any other security into which
such stock shall have been changed or for which it shall have been exchanged,
and if the Board in its sole discretion determines that such change equitably
requires an adjustment in the Options then outstanding under the Plan, such
adjustment shall be made in accordance with the determination of the Board.  No
adjustments shall be required by reason of the issuance or sale by the Company
for cash or other consideration of additional shares of its stock or securities
convertible into or exchangeable for shares of its stock.

          (b)  Dissolution or Liquidation.  In the event of the proposed
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dissolution or liquidation of the Company, each Optionee shall be notified as
soon as practicable prior to the effective date of such proposed transaction.
The Optionee shall have the right to exercise an Option until ten (10) days
prior to such transaction as to all of the Optioned Stock covered thereby,
including Shares as to which the Option would not otherwise be exercisable.  To
the extent that it has not been previously exercised, an Option shall terminate
immediately prior to the consummation of such proposed action.

          (c)  Change in Control.  In the event of a "Change in Control" of the
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Company, as defined in paragraph (d) below, then the following provisions shall
apply:

               (i)    Merger or Asset Sale.  If the Change in Control is a 
                      -------------------- 
merger of the Company with or into another corporation as described in Section
10(d)(ii), or a sale of substantially all of the assets of the Company as
described in Section 10(d)(iii), outstanding Options may be assumed or
equivalent options may be substituted by the successor corporation or a Parent
or Subsidiary thereof (the "Successor Corporation"). If an Option is assumed or
substituted for, the Option or equivalent option shall continue to be
exercisable as provided in Section 4 hereof for so long as the Optionee serves
as a Director, or as a director of the Successor Corporation. Following such
assumption or substitution, if the Optionee's status as a Director or director
of the Successor Corporation, as applicable, is terminated other than upon a
voluntary resignation by the Optionee, the Option or option shall become fully
exercisable, including as to Shares for which it would not otherwise be
exercisable. Thereafter, the Option or option shall remain exercisable in
accordance with Sections 8(c) through (e) above.

                      If the Successor Corporation does not assume an 
outstanding Option or substitute for it an equivalent option, the Option shall
become fully vested and exercisable, 

                                      -7-

 
including as to Shares for which it would not otherwise be exercisable. In such
event the Board shall notify the Optionee that the Option shall be fully
exercisable for a period of thirty (30) days from the date of such notice, and
upon the expiration of such period the Option shall terminate.

                      For the purposes of this Section 10(c)(i), an Option 
shall be considered assumed if, following the merger or sale of assets, the
Option confers the right to purchase or receive, for each Share of Optioned
Stock subject to the Option immediately prior to the merger or sale of assets,
the consideration (whether stock, cash, or other securities or property)
received in the merger or sale of assets by holders of Common Stock for each
Share held on the effective date of the transaction (and if holders were offered
a choice of consideration, the type of consideration chosen by the holders of a
majority of the outstanding Shares).

               (ii)   Other Changes in Control.  If the Change in Control is a
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change in ownership of the Company or a change in the composition of the Board
as described in Section 10(d)(i) or 10(d)(iv), following such Change in Control
an outstanding Option shall continue to be exercisable as provided in Section 4
hereof for so long as the Optionee serves as a Director.  If the Optionee's
status as a Director is terminated other than upon a voluntary resignation by
the Optionee, the Option shall become fully exercisable, including as to Shares
for which it would not otherwise be exercisable.  Thereafter, the Option or
option shall remain exercisable in accordance with Sections 8(c) through (e)
above.

          (d)  Definition of "Change in Control".  For purposes of this Section
               ---------------------------------                               
10, a "Change in Control" means the happening of any of the following:

               (i)    when any "person" or "group" of persons, as such terms are
used in Sections 13(d) and 14(d) of the Exchange Act (other than the Company, a
Subsidiary or a Company employee benefit plan, including any trustee of such
plan acting as trustee) is or becomes the "beneficial owner" (as defined in Rule
13d-3 under the Exchange Act), directly or indirectly, of securities of the
Company representing more than fifty percent (50%) of the combined voting power
of the Company's then outstanding securities entitled to vote generally in the
election of directors; provided that "person" shall not include any person (or
any person acting as a group) which, as of the date of the adoption of this 1995
Director Option Plan, is the "beneficial owner" of securities of the Company
representing more than fifty percent (50%) of the combined voting power of the
Company's outstanding securities entitled to vote generally in the election of
directors;

               (ii)   a merger or consolidation of the Company with any other
corporation, 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;

               (iii)  the stockholders of the Company approve an agreement for 
the sale or disposition by the Company of all or substantially all the Company's
assets; or

                                      -8-

 
               (iv)   a change in the composition of the Board occurring within
any twelve- month period as a result of which fewer than a majority of the
members of the Board are Incumbent Directors.  "Incumbent Directors" shall mean
Directors who either are (A) Directors as of the date the Plan is approved by
the stockholders, or (B) who are elected or nominated for election to the Board
with the affirmative votes of at least a majority of the Incumbent Directors who
are members of the Board at the time of such election or nomination.  The term
"Incumbent Director" shall not include an individual not otherwise an Incumbent
Director whose election, nomination or appointment is in connection with an
actual or threatened proxy contest relating to the election of directors of the
Company.

     11.  Amendment and Termination of the Plan.
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          (a)  Amendment and Termination.  Except as set forth in Section 4, the
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Board may at any time amend, alter, suspend, or discontinue the Plan, but no
amendment, alteration, suspension, or discontinuation shall be made which would
impair the rights of any Optionee under any grant theretofore made, without his
or her consent.  In addition, to the extent necessary and desirable to comply
with Rule 16b-3 under the Exchange Act (or any other applicable law or
regulation), the Company shall obtain stockholder approval of any Plan amendment
in such a manner and to such a degree as required.

          (b)  Effect of Amendment or Termination.  Any such amendment or
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termination of the Plan shall not affect Options already granted and such
Options shall remain in full force and effect as if this Plan had not been
amended or terminated.

     12.  Time of Granting Options.  The date of grant of an Option shall, for
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all purposes, be the date determined in accordance with Section 4 hereof.

     13.  Conditions Upon Issuance of Shares.  Shares shall not be issued
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pursuant to the exercise of an Option unless the exercise of such Option and the
issuance and delivery of such Shares pursuant thereto shall comply with all
relevant provisions of law, including, without limitation, the Securities Act of
1933, as amended, the Exchange Act, the rules and regulations promulgated
thereunder, state securities laws, and the requirements of any stock exchange
upon which the Shares may then be listed, and shall be further subject to the
approval of counsel for the Company with respect to such compliance.

          As a condition to the exercise of an Option, the Company may require
the person exercising such Option to represent and warrant at the time of any
such exercise that the Shares are being purchased only for investment and
without any present intention to sell or distribute such Shares, if, in the
opinion of counsel for the Company, such a representation is required by any of
the aforementioned relevant provisions of law.

          Inability of the Company to obtain authority from any regulatory body
having jurisdiction, which authority is deemed by the Company's counsel to be
necessary to the lawful 

                                      -9-

 
issuance and sale of any Shares hereunder, shall relieve the Company of any
liability in respect of the failure to issue or sell such Shares as to which
such requisite authority shall not have been obtained.

     14.  Reservation of Shares.  The Company, during the term of this Plan,
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will at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.

     15.  Option Agreement.  Options shall be evidenced by written option
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agreements in such form as the Board shall approve.

     16.  Stockholder Approval.  Continuance of the Plan shall be subject to
          --------------------                                              
approval by the stockholders of the Company at or prior to the first annual
meeting of stockholders held subsequent to the granting of an Option hereunder.
Such stockholder approval shall be obtained in the degree and manner required
under applicable state and federal law.

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