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                                                                   EXHIBIT 10.31
                                FORM OF AGREEMENT
                             WITH EXECUTIVE OFFICER
                          RELATING TO CHANGE OF CONTROL



                                                                  ________, 19__


First Name- Initial/Last Name-
Title-
Cygnus, Inc.
400 Penobscot Drive
Redwood City, CA  94063

Dear Salutation-:

          Cygnus, Inc., a Delaware corporation (the "Company"), considers the
establishment and maintenance of a sound and vital management to be essential to
protecting and enhancing the best interests of the Company and its shareholders.
In this connection, the Company recognizes that, as is the case with many
publicly held corporations, the possibility of a change in control may arise and
that such possibility, and the uncertainty and questions which it may raise
among management, may result in the departure or distraction of management
personnel to the detriment of the Company and its shareholders.  

          In view of the above, the Board of Directors of the Company (the
"Board") has determined that appropriate steps should be taken to reinforce and
encourage the continued attention and dedication of members of the Company's
management to their assigned duties without distraction in circumstances arising
from the possibility of a change in control of the Company.  In particular, the
Board believes it important, should the Company or its shareholders receive a
proposal for transfer of control of the Company, that you be able to assess and
advise the Board whether such proposal would be in the best interests of the
Company and its shareholders and to take such other action regarding such
proposal as the Board might determine to be appropriate, without being
influenced by the uncertainties of your own situation.

          In order to induce you to remain in the employ of the Company, this
letter agreement, which has been approved by the Board, sets forth the severance
benefits which the Company agrees will be provided to you in the event your
employment with the Company is terminated subsequent to a "change in control" of
the Company under the circumstances described below.  This letter agreement
includes, as if set forth in full 

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                                                                     Page 2

herein, those definitions and miscellaneous terms and provisions set forth in 
Exhibit A hereto, which exhibit is specifically incorporated herein by this 
reference.

     1.   AGREEMENT TO PROVIDE SERVICES; RIGHT TO TERMINATE.

          (i)  Except as otherwise provided in paragraph (ii) below, the Company
or you may terminate your employment at any time, subject to the Company's
providing the benefits hereinafter specified in accordance with the terms
hereof.

          (ii) In the event a tender offer or exchange offer is made by a Person
(as defined herein) for more than 50% of the combined voting power of the
Company's outstanding securities ordinarily having the right to vote at
elections of directors ("Voting Securities"), or in the event of any
solicitation of proxies or written consents not approved by the Board, you agree
that such event will not lead you to leave the employ of the Company (other than
as a result of Disability or upon Retirement, as such terms are defined herein)
and will render the services contemplated in the recitals to this Agreement
until such tender offer or exchange offer has been abandoned or terminated or a
"change in control" of the Company, as defined herein, has occurred.   

     2.   TERM OF AGREEMENT.  This Agreement shall commence on the date hereof
and shall continue in effect until December 31, 19__; provided, however, that
commencing on January 1, 19__ and each January 1 thereafter, the term of this
Agreement shall automatically be extended for one additional year unless at
least 90 days prior to such January 1st date, the Company or you shall have
given notice that this Agreement shall not be extended; and provided, further,
that this Agreement shall continue in effect for a period of twenty-four (24)
months beyond the term provided herein if a change in control of the Company
shall have occurred during such term.  Notwithstanding anything in this
Section 2 to the contrary, this Agreement shall terminate if you or the Company
terminate your employment prior to a change in control of the Company.  

     3.   TERMINATION FOLLOWING CHANGE IN CONTROL.  If any of the events
described in Exhibit A hereto constituting a change in control of the Company
shall have occurred, you shall be entitled to the benefits provided in
paragraphs (iii) and (iv) of Section 4 hereof upon the termination of your
employment within twenty-four (24) months after such event, unless such
termination is (a) because of your death or Retirement, (b) by the Company for
Cause or Disability or (c) by you other than for Good Reason (as all such
capitalized terms are defined herein).

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                                                                     Page 3

           Any purported termination by the Company or by you following a change
in control shall be communicated by written Notice of Termination to the other
party hereto.  For purposes of this Agreement, a "Notice of Termination" shall
mean a notice which shall indicate the specific termination provision in this
Agreement relied upon.


     4.   COMPENSATION UPON TERMINATION OR DURING DISABILITY; OTHER AGREEMENTS.

          (i)  During any period following a change in control that you fail to
perform your duties as a result of incapacity due to physical or mental illness,
you shall continue to receive your salary at the rate then in effect and any
benefits or awards under any Plans shall continue to accrue during such period,
to the extent not inconsistent with such Plans, until your employment is
terminated pursuant to and in accordance with the provisions hereof. 
Thereafter, your benefits shall be determined in accordance with the Plans then
in effect.

          (ii)  If your employment shall be terminated for Cause following a
change in control of the Company, the Company shall pay you your salary through
the Date of Termination at the rate in effect just prior to the time a Notice of
Termination is given plus any benefits or awards (including both the cash and
stock components) which pursuant to the terms of any Plans have been earned or
become payable, but which have not yet been paid to you.  Thereupon the Company
shall have no further obligations to you under this Agreement.

          (iii)       Subject to Section 7 hereof, if, within twenty-four (24)
months after a change in control of the Company shall have occurred, as defined
herein, your employment by the Company shall be terminated (a) by the Company
other than for Cause, Disability or Retirement or (b) by you for Good Reason,
then, by no later than the fifth day following the Date of Termination (except
as otherwise provided), you shall be entitled, without regard to any contrary
provisions of any Plan, to the benefits as provided below:

               (A)  the Company shall pay your salary through the Date of
     Termination at the rate in effect just prior to the time a Notice of
     Termination is given plus any benefits or awards (including both the cash
     and stock components) which pursuant to the terms of any Plans have been
     earned or become payable, but which have not yet been paid to you
     (including amounts which previously had been deferred at your request); 

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                                                                     Page 4

               (B)  as severance pay and in lieu of any further salary for
     periods subsequent to the Date of Termination, the Company shall pay to you
     an amount in cash equal to one times (1x) your annual base salary in effect
     immediately prior to the change in control plus the amount of any cash
     bonus awards made to you with respect to the Company's full fiscal year
     immediately preceding the change of control; and

               (C)  with respect to any stock options, restricted stock, share
     rights or other incentive compensation awards made to you by the Company
     which (i) were originally denominated in Common Stock of the Company, (ii)
     are subject to a vesting requirement (based solely upon your period of
     continuous employment by the Company or a Successor (as defined in Section
     5 hereof)) and (iii) have been assumed or replaced by a Successor, such
     vesting requirement shall be automatically accelerated by 12 months from
     the Date of Termination.  

          (iv)  Following a change in control of the Company, unless you are
terminated for Cause, Disability or Retirement or you terminate your employment
other than for Good Reason, the Company shall maintain in full force and effect,
for the continued benefit of you and your dependents for a period terminating on
the earliest of (a) one year after the Date of Termination, (b) the commencement
date of equivalent benefits from a new employer or (c) your normal retirement
date under the terms of the Retirement Policy, all insured and self-insured
employee welfare benefit Plans in which you were entitled to participate
immediately prior to the Date of Termination, provided that your continued
participation is possible under the general terms and provisions of such Plans
(and any applicable funding media) and you continue to pay an amount equal to
your regular contribution under such plans for such participation.  If, at the
end of two years after the Termination Date, you have not reached your normal
retirement date and you have not previously received or are not then receiving
equivalent benefits from a new employer, the Company shall arrange, at its sole
cost and expense, to enable you to convert your and your dependents' coverage
under such Plans to individual policies or programs upon the same terms as
employees of the Company may apply for such conversions.  In the event that your
participation in any such Plan is barred, the Company, at its sole cost and
expense, shall arrange to have issued for the benefit of you and your dependents
individual policies of insurance providing benefits substantially similar (on an
after-tax basis) to those which you otherwise would have been entitled to
receive under such Plans pursuant to this paragraph (iv) or, if such insurance
is not available at a reasonable cost to the Company, the Company shall
otherwise provide you and your dependents equivalent benefits (on an after-tax
basis).  You shall not be 

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                                                                     Page 5

required to pay any premiums or other charges in an amount greater than that 
which you would have paid in order to participate in such Plans.

          (v)  Except as specifically provided in paragraph (iv) above, the
amount of any payment provided for in this Section 4 shall not be reduced,
offset or subject to recovery by the Company by reason of any compensation
earned by you as the result of employment by another employer after the Date of
Termination, or otherwise.

     5.   SUCCESSORS; BINDING AGREEMENT.

          (i)  Upon your written request, the Company will seek to have any
Successor (as hereinafter defined), by agreement in form and substance
satisfactory to you, assent to the fulfillment by the Company of its obligations
under this Agreement.  Failure of the Company to obtain such assent at least
three business days prior to the time a Person becomes a Successor (or where the
Company does not have at least three business days' advance notice that a Person
may become a Successor, within one business day after having notice that such
Person may become or has become a Successor) shall constitute Good Reason for
termination by you of your employment and, if a change in control of the Company
has occurred, shall entitle you immediately to the benefits provided in
paragraphs (iii) and (iv) of Section 4 hereof upon delivery by you of a Notice
of Termination.  For purposes of this Agreement, "Successor" shall mean any
Person that succeeds to, or has the practical ability to control (either
immediately or with the passage of time), the Company's business directly, by
merger or consolidation, or indirectly, by purchase of the Company's Voting
Securities, all or substantially all of its assets or otherwise.

          (ii) This Agreement shall inure to the benefit of and be enforceable
by your personal or legal representatives, executors, administrators,
successors, heirs, distributees, devisees and legatees.  If you should die while
any amount would still be payable to you hereunder if you had continued to live,
all such amounts, unless otherwise provided herein, shall be paid in accordance
with the terms of this Agreement to your devisee, legatee or other designee or,
if there be no such designee, to your estate.

          (iii)     For purposes of this Agreement, the "Company" shall include
any corporation or other entity which is the surviving or continuing entity in
respect of any merger, consolidation or form of business combination in which
the Company ceases to exist.

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                                                                     Page 6


     6.   FEES AND EXPENSES; MITIGATION.

          (i)  The Company shall pay all reasonable legal fees and related
expenses incurred by you in connection with the Agreement following a change in
control of the Company, including, without limitation, (a) all such fees and
expenses, if any, incurred in contesting or disputing any such termination or
(b) your seeking to obtain or enforce any right or benefit provided by this
Agreement.

          (ii) You shall not be required to mitigate the amount of any payment
the Company becomes obligated to make to you in connection with this Agreement,
by seeking other employment or otherwise.

     7.   TAXES.  All payments to be made to you under this Agreement will be
subject to required withholding of federal, state and local income and
employment taxes.

     8.   SURVIVAL.  The respective obligations of, and benefits afforded to,
the Company and you as provided in Sections 4, 5, 6, 7 and 8 of this Agreement
shall survive termination of this Agreement.

     9.   EMPLOYEE'S COMMITMENT.  You agree that subsequent to your period of
employment with the Company, you will not at any time communicate or disclose to
any unauthorized person, without the written consent of the Company, any
proprietary or other confidential information concerning the Company or any
subsidiary which, if disclosed, would have a material adverse effect upon the
business or operations of the Company and its subsidiaries, taken as a whole; it
being understood, however, that the obligations of this Section 9 shall not
apply to the extent that the aforesaid matters (a) are disclosed in
circumstances where you are legally required to do so or (b) become generally
known to and available for use by the public otherwise than by your wrongful act
or omission.

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                                                                     Page 7

          If this letter correctly sets forth our agreement on the subject
matter hereof, kindly sign and return to the Company the enclosed copy of this
letter which will then constitute our agreement on this subject.

               
                                              Very truly yours, 

                                              CYGNUS, INC.


                                              By
                                                   ---------------------------
                                                   Signee-
                                                   Signee Title-
Agreed to this          day of
               --------
                        , 19  .
------------------------    --
 
-------------------------------------                                        
First Name- Initial/Last Name-

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                                    EXHIBIT A

                        TERMS, PROVISIONS AND DEFINITIONS
                           APPLICABLE TO CYGNUS, INC. 
                          CHANGE OF CONTROL AGREEMENTS


I.  DEFINITIONS.

        For purposes of the letter agreement to which this Exhibit A is
    attached, the terms set forth below shall be defined as follows:

    CAUSE.     Termination by the Company of your employment for "Cause" shall 
    mean termination upon (a) the willful and continued failure by you to
    perform substantially your duties with the Company (other than any such
    failure resulting from your incapacity due to physical or mental illness)
    after a demand for substantial performance is delivered to you by the
    Chairman of the Board or President of the Company which specifically
    identifies the manner in which such executive believes that you have not
    substantially performed your duties, or (b) the willful engaging by you in
    illegal conduct which is materially and demonstrably injurious to the
    Company.  For purposes of this definition, no act, or failure to act, on
    your part shall be considered "willful" unless done, or omitted to be done,
    by you in bad faith and without reasonable belief that your action or
    omission was in, or not opposed to, the best interests of the Company.  Any
    act, or failure to act, based upon authority given pursuant to a resolution
    duly adopted by the Board or based upon the advice of counsel for the
    Company shall be conclusively presumed to be done, or omitted to be done, by
    you in good faith and in the best interests of the corporation.  It is also
    expressly understood that your attention to matters not directly related to
    the business of the Company shall not provide a basis for termination for
    Cause so long as the Board has approved your engagement in such activities. 
    Notwithstanding the foregoing, you shall not be deemed to have been
    terminated for Cause unless and until there shall have been delivered to you
    a copy of a resolution duly adopted by the affirmative vote of not less than
    three quarters of the entire membership of the Board at a meeting of the
    Board called and held for the purpose (after reasonable notice to you and an
    opportunity for you, together with your counsel, to be heard before the
    Board), finding that in the good faith opinion of the Board you were guilty
    of the conduct set forth above in (a) or (b) of this definition and
    specifying the particulars thereof in detail.

                                  i
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    CHANGE IN CONTROL.   A "change in control" of the Company shall mean a
    change in control of a nature that would be required to be reported
    (assuming such event has not been "previously reported") in response to
    Item 1(a) of the Current Report on Form 8-K, as in effect on the date
    hereof, pursuant to Section 13 or 15(d) of the Exchange Act; provided that,
    without limitation, such a change in control shall be deemed to have
    occurred at such time as (a) any Person is or becomes the "beneficial owner"
    (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly,
    of 50% or more of the combined voting power of the Company's Voting
    Securities; or (b) individuals who constitute the Board on the date hereof
    (the "Incumbent Board") cease for any reason to constitute at least a
    majority thereof, provided that any person becoming a director subsequent to
    the date hereof whose election, or nomination for election by the Company's
    shareholders, was approved by a vote of at least three quarters of the
    directors comprising the Incumbent Board (either by a specific vote or by
    approval of the proxy statement of the Company in which such person is named
    as a nominee for director, without objection to such nomination) shall be,
    for purposes of this clause (b), considered as though such person were a
    member of the Incumbent Board.  Notwithstanding anything in the foregoing to
    the contrary, no change in control shall be deemed to have occurred by
    virtue of any transaction which results in you, or a group of Persons which
    includes you, acquiring, directly or indirectly, 30% or more of the combined
    voting power of the Company's Voting Securities.

    DATE OF TERMINATION.  "Date of Termination" following a change in control
    shall mean (a) if your employment is to be terminated for Disability, thirty
    (30) days after Notice of Termination is given (provided that you shall not
    have returned to the performance of your duties on a full-time basis during
    such thirty (30) day period), (b) if your employment is to be terminated by
    the Company for Cause or by you for Good Reason, the date specified in the
    Notice of Termination, or (c) if your employment is to be terminated by the
    Company for any reason other than Cause, the date specified in the Notice of
    Termination, which in no event shall be a date earlier than ninety (90) days
    after the date on which a Notice of Termination is given, unless an earlier
    date has been expressly agreed to by you in writing either in advance of, or
    after, receiving such Notice of Termination.  In the case of termination by
    the Company of your employment for Cause, if you have not previously
    expressly agreed in writing to the termination, then within thirty (30) days
    after receipt by you of the Notice of Termination with respect thereto, you
    may notify the Company that a dispute exists concerning the termination, in
    which event the Date of Termination shall be the date set either by mutual
    written agreement of the parties or through a judicial determination. 
    During the pendency 

                                  ii
<PAGE>


    of any such dispute, the Company will continue to pay you your full 
    compensation in effect just prior to the time the Notice of Termination is 
    given and until the dispute is resolved in accordance with the terms hereof.

    DISABILITY.    Termination by the Company of your employment based on
    "Disability" shall mean termination because of your absence from your duties
    with the Company on a full time basis for one hundred eighty (180)
    consecutive days as a result of your incapacity due to physical or mental
    illness, unless within thirty (30) days after Notice of Termination (as
    defined herein) is given to you following such absence you shall have
    returned to the full time performance of your duties.

    GOOD REASON.   Termination by you of your employment for "Good Reason" shall
    mean termination based on:

          (A)   an adverse change in your status or position(s) as an officer
    of the Company as in effect immediately prior to the change in control,
    including, without limitation, any adverse change in your status or position
    as a result of a material diminution in your duties or responsibilities
    (other than, if applicable, any such change directly attributable to the
    fact that the Company is no longer publicly owned) or the assignment to you
    of any duties or responsibilities which, in your reasonable judgment, are
    inconsistent with such status or position(s), or any removal of you from or
    any failure to reappoint or reelect you to such position(s) (except in
    connection with the termination of your employment for Cause, Disability or
    Retirement or as a result of your death or by you other than for Good
    Reason);

          (B)  a reduction by the Company in your base salary as in effect
    immediately prior to the change in control;

          (C)  the failure by the Company to continue in effect any Plan (as
    defined herein) in which you are participating at the time of the change in
    control of the Company (or Plans providing you with at least substantially
    similar benefits) other than as a result of the normal expiration of any
    such Plan in accordance with its terms as in effect at the time of the
    change in control, or the taking of any action, or the failure to act, by
    the Company which would adversely affect your continued participation in any
    of such Plans on at least as favorable a basis to you as is the case on the
    date of the change in control or which would materially reduce your benefits
    in the future under any of such Plans or deprive you of any material benefit
    enjoyed by you at the time of the change in control;

                                  iii
<PAGE>

          (D)  the failure by the Company to provide and credit you with the
    number of paid vacation days to which you are then entitled in accordance
    with the Company's normal vacation policy as in effect immediately prior to
    the change in control;

          (E)  the Company's requiring you to be based more than 50 miles from
    where your office is located immediately prior to the change in control
    except for required travel on the Company's business to an extent
    substantially consistent with the business travel obligations which you
    undertook on behalf of the Company prior to the change in control;

          (F)  the failure by the Company to obtain from any Successor (as
    defined herein) the assent to this Agreement as contemplated by the terms
    hereof;

          (G)  any purported termination by the Company of your employment
    which is not effected pursuant to a Notice of Termination satisfying the
    requirements of paragraph (v) below (and, if applicable, paragraph (iii)
    above); and for purposes of this Agreement, no such purported termination
    shall be effective; or

          (H)  any refusal by the Company to continue to allow you to attend to
    matters or engage in activities not directly related to the business of the
    Company which, prior to the change in control, you were permitted by the
    Board to attend to or engage in.


    PERSON.   "Person" shall mean and include any individual, corporation,
    partnership, group, association or other "person," as such term is used in
    Section 14(d) of the Securities Exchange Act of 1934 (the "Exchange Act"),
    other than the Company, a wholly-owned subsidiary of the Company or any
    employee benefit plan(s) sponsored by the Company.

    PLAN.    The term "Plan" shall mean any compensation plan such as an
    incentive, stock option or restricted stock plan or any pension or profit
    sharing plan.
    
    RETIREMENT.    Termination by you or by the Company of your employment based
    on "Retirement" shall mean termination on or after your normal retirement
    date under the terms of the Company's retirement policy (or any successor or
    substitute 

                                  iv
<PAGE>

    policy or policies of the Company put into effect prior to a change in 
    control) (the "Retirement Policy").


II. MISCELLANEOUS PROVISIONS.

        The following terms and provisions shall be included in, and
    incorporated into, the letter agreement to which this Exhibit A is attached:

    1.  NOTICE.  Notices and all other communications provided for in the
        Agreement shall be in writing and shall be deemed to have been duly
        given when delivered or mailed by United States registered mail, return
        receipt requested, postage prepaid and addressed, in the case of the
        Company, to Cygnus, Inc., 400 Penobscot Drive, Redwood City, California
        94063, Attention: Chief Executive Officer or, in the case of the
        undersigned employee, to the address set forth below his signature,
        provided that all notices to the Company shall be directed to the
        attention of the Chairman of the Board or President of the Company, with
        a copy to the Secretary of the Company, or to such other address as
        either party may have furnished to the other in writing in accordance
        herewith, except that notice of change of address shall be effective
        only upon receipt.

    2.  MISCELLANEOUS.  No provision of this Agreement may be modified, waived
        or discharged unless such modification, waiver or discharge is agreed to
        in a writing signed by you and the Chairman of the Board or President of
        the Company.  No waiver by either party hereto at any time of any breach
        by the other party hereto of, or of compliance with, any condition or
        provision of this Agreement to be performed by such other party shall be
        deemed a waiver of similar or dissimilar provisions or conditions at the
        same or at any prior or subsequent time.  No agreements or
        representations, oral or otherwise, express or implied, with respect to
        the subject matter hereof have been made by either party which are not
        expressly set forth in this Agreement.  The validity, interpretation,
        construction and performance of this Agreement shall be governed by the
        laws of the State of California.


    3.  VALIDITY.  The invalidity or unenforceability of any provision of this
        Agreement shall not affect the validity or enforceability of any other
        provision of this Agreement, which shall remain in full force and
        effect.

                                  v
<PAGE>

    4.  RELATED AGREEMENTS.  To the extent that any provision of any other
        agreement between the Company or any of its subsidiaries and you shall
        limit, qualify or be inconsistent with any provision of this Agreement,
        then for purposes of this Agreement, while the same shall remain in
        force, the provision of this Agreement shall control and such provision
        of such other agreement shall be deemed to have been superseded, and to
        be of no force or effect, as if such other agreement had been formally
        amended to the extent necessary to accomplish such purpose.

    5.  COUNTERPARTS.  This Agreement may be executed in several counterparts,
        each of which shall be deemed to be an original but all of which
        together will constitute one and the same instrument.

                                  vi