<PAGE>
 
                                                                    EXHIBIT 10.4

                          CHANGE OF CONTROL AGREEMENT

                                    between

                                   KEN TAPMAN

                                      and

                              PROCYTE CORPORATION

                                  dated as of

                                 APRIL 27, 1998

<PAGE>
 
                          CHANGE OF CONTROL AGREEMENT

     This Change of Control Agreement (this "Agreement"), dated as of April 27,
1998 is between ProCyte Corporation, a Washington corporation (the "Company"),
and Ken Tapman (the "Executive").

     The Board of Directors of the Company (the "Board") has determined that it
is in the best interests of the Company and its stockholders to ensure that the
Company will have the continued dedication of the Executive, notwithstanding the
possibility, threat or occurrence of a Change of Control (as defined in Section
1.1 below) of the Company.  The Board believes it is imperative to diminish the
inevitable distraction of the Executive arising from the personal uncertainty
and risks created by a pending or threatened Change of Control, to encourage the
Executive's full attention and dedication to the Company currently and in the
event of any threatened or pending Change of Control, and to provide the
Executive with reasonable compensation and benefit arrangements upon a Change of
Control.

     In order to accomplish these objectives, the Board has caused the Company
to enter into this Agreement.

                                1.  DEFINITIONS

1.1  CHANGE OF CONTROL

     Shall have the definition set forth in Appendix A to this Agreement, which
is hereby incorporated by reference.

1.2  CHANGE OF CONTROL DATE

     Shall mean the first date on which a Change of Control occurs.

1.3  EMPLOYMENT AGREEMENT

     Shall mean the Employment Agreement between Executive and the Company dated
as of the same date as this Agreement.

1.4  EMPLOYMENT PERIOD

     Shall mean the two-year period commencing on the Change of Control Date and
ending on the second anniversary of such date.

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                                    2.  TERM

     The term of this Agreement ("Term") shall be for a period of two years from
the date of this Agreement as first entered above, at which time this Agreement
shall terminate without further action by either the Company or the Executive,
provided, however, that if a Change of Control occurs during the Term, the Term
shall automatically extend for the duration of the Employment Period.

                                 3.  EMPLOYMENT

3.1  EMPLOYMENT PERIOD

     During the Employment Period, the Company hereby agrees to continue the
Executive in its employ or in the employ of its affiliated companies, and the
Executive hereby agrees to remain in the employ of the Company or its affiliated
companies, in accordance with the terms and provisions of this Agreement;
provided, however, that either the Company or the Executive may terminate the
employment relationship subject to the terms of this Agreement, or subject to
the terms of the Employment Agreement.

3.2  POSITION AND DUTIES

     During the Employment Period, the Executive's position, authority, duties
and responsibilities shall be at least commensurate in all material respects
with the most significant of those held, exercised and assigned at any time
during the 90-day period immediately preceding the Change of Control Date.

3.3  LOCATION

     During the Employment Period, the Executive's services shall be performed
at the Company's headquarters on the Change of Control Date or any office which
is subsequently designated as the headquarters of the Company and is less than
30 miles from such location.

3.4  EMPLOYMENT AT WILL

     The Executive and the Company acknowledge that, except as may otherwise be
provided under any other written agreement between the Executive and Company,
the employment of the Executive by the Company or its affiliated companies is
"at will" and may be terminated by either the Executive or the Company or its
affiliated companies at any time with or without cause.  Moreover, if prior to
the Change of Control Date, the Executive's employment with the Company or its
affiliated companies terminates for any reason, then the Executive shall have no
further rights 

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under this Agreement; provided, however, that Company may not avoid liability
for any termination payments which would have been required during the
Employment Period pursuant to Section 8 below by terminating the Executive prior
to the Employment Period where such termination is carried out in anticipation
of a Change of Control and the principal motivating purpose is to avoid
liability for such termination payment.

                            4.  ATTENTION AND EFFORT

     During the Employment Period, and excluding any periods of vacation and
sick leave to which the Executive is entitled, the Executive will devote all of
his productive time, ability, attention and effort to the business and affairs
of the Company and the discharge of the responsibilities assigned to him
hereunder, and will use his reasonable best efforts to perform faithfully and
efficiently such responsibilities.  It shall not be a violation of this
Agreement for the Executive to:

      A.  serve on corporate, civic or charitable boards or committees,

      B.  deliver lectures, fulfill speaking engagements or teach at educational
          institutions, and

      C.  manage personal investments, so long as such activities do not
          significantly interfere with the performance of the Executive's
          responsibilities in accordance with this Agreement.

     It is expressly understood and agreed that to the extent any such
activities have been conducted by the executive prior to the Employment Period,
the continued conduct of such activities (or the conduct of activities similar
in nature and scope thereto) during the Employment Period shall not thereafter
be deemed to interfere with the performance of the Executive's responsibilities
to the Company.

                                5.  COMPENSATION

     As long as the Executive remains employed by the Company during the
Employment Period, the Company agrees to pay or cause to be paid to the
Executive, and the Executive agrees to accept in exchange for the services
rendered hereunder by him, the following compensation:

5.1  SALARY

     The Executive shall receive an annual base salary (the "Annual Base
Salary"), at least equal to the annual salary established by the Board or the
Compensation Committee of the Board (the "Compensation Committee") for the
fiscal year in which 

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the Change of Control Date occurs. The Annual Base Salary shall be paid in
substantially equal installments and at the same intervals as the salaries of
other executives of the Company are paid. The Board or the Compensation
Committee shall review the Annual Base Salary at least annually and shall
determine in good faith and consistent with any generally applicable Company
policy any increases for future years.

5.2  BONUS

     In addition to Annual Base Salary, the Executive shall be awarded, for each
fiscal year ending during the Employment Period, an annual bonus (the "Annual
Bonus") in cash at least equal to the average annualized (for any fiscal year
consisting of less than 12 full months) bonus paid or payable, including by
reason of any deferral, to the Executive by the Company and its affiliated
companies in respect of the three fiscal years immediately preceding the fiscal
year in which the Change of Control Date occurs; provided, however, that amounts
paid or payable by the Company to Executive as "Earnout Payments" under the
Employment Agreement shall not be considered bonuses for such determination.
Each such Annual Bonus shall be paid no later than 90 days after the end of the
fiscal year for which the Annual Bonus is awarded, unless the Executive shall
elect to defer the receipt of such Annual Bonus.

                                  6.  BENEFITS

6.1  INCENTIVE, RETIREMENT AND WELFARE BENEFIT PLANS; VACATION

     During the Employment Period, the Executive shall be entitled to
participate, subject to and in accordance with applicable eligibility
requirements, in such fringe benefit programs as shall be generally made
available to other executives of the Company and its affiliated companies from
time to time during the Employment Period by action of the Board (or any person
or committee appointed by the Board to determine fringe benefit programs and
other emoluments), including, without limitation, paid vacations; any stock
purchase, savings or retirement plan, practice, policy or program; and all
welfare benefit plans, practices, policies or programs (including, without
limitation, medical, prescription, dental, disability, salary continuance,
employee life, group life, accidental death and travel accident insurance plans
or programs).

6.2  EXPENSES

     During the Employment Period, the Executive shall be entitled to receive
prompt reimbursement for all reasonable employment expenses incurred by him in

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accordance with the policies, practices and procedures of the Company and its
affiliated companies in effect for the executives of the Company and its
affiliated companies during the Employment Period.

                                7.  TERMINATION

     During the Employment Period and subject to the Employment Agreement, if
applicable, employment of the Executive may be terminated as follows but, in any
case, the nondisclosure provisions set forth in Section 10 hereof shall survive
the termination of this Agreement and the termination of the Executive's
employment with the Company.

7.1  BY THE COMPANY OR THE EXECUTIVE

     At any time during the Employment Period, the Company may terminate the
employment of the Executive with or without Cause (as defined below), and the
Executive may terminate his employment for Good Reason (as defined below) or for
any reason, upon giving Notice of Termination (as defined below).

7.2  AUTOMATIC TERMINATION

     This Agreement and the Executive's employment during the Employment Period
shall terminate automatically upon the death or Total Disability of the
Executive.  The term "Total Disability" as used herein shall mean the
Executive's inability (with such accommodation as may be required by law and
which places no undue burden on the Company), as determined by a physician
selected by the Company and acceptable to the Executive, to perform the duties
set forth in Section 3.2 hereof for a period or periods aggregating 120 calendar
days in any 12 month period as a result of physical or mental illness, loss of
legal capacity or any other cause beyond the Executive's control, unless the
Executive is granted a leave of absence by the Board.  The Executive and the
Company hereby acknowledge that the duties specified in Section 3.2 hereof are
essential to Executive's position and that Executive's ability to perform those
duties is the essence of this Agreement.

7.3  NOTICE OF TERMINATION

     Any termination by the Company or by the Executive during the Employment
Period shall be communicated by Notice of Termination to the other party given
in accordance with Section 12 hereof.  The term "Notice of Termination" shall
mean a written notice which:

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     A.  indicates the specific termination provision in this Agreement relied
         upon; and

     B.  to the extent applicable, sets forth in reasonable detail the facts and
         circumstances claimed to provide a basis for termination of the
         Executive's employment under the provision so indicated.

     The failure by the Executive or Company to set forth in the Notice of
Termination any fact or circumstance which contributes to a showing of Good
Reason or Cause shall not waive any right of the Executive or the Company
hereunder or preclude the Executive or the Company from asserting such fact or
circumstance in enforcing the Executive's or the Company's rights hereunder.

7.4  DATE OF TERMINATION

     During the Employment Period, "Date of Termination" means:

     A.  if the Executive's employment is terminated by reason of death, the
         last day of the calendar month in which the Executive's death occurs,

     B.  if the Executive's employment is terminated by reason of Total
         Disability, immediately upon a determination by the Company of the
         Executive's Total Disability; and

     C.  in all other cases, five days after the date of personal delivery or
         mailing of the Notice of Termination.

     The Executive's employment and performance of services will continue during
such five-day period; provided, however, that the Company may, upon notice to
the Executive and without reducing the Executive's compensation during such
period, excuse the Executive from any or all of his duties during such period.

                            8.  TERMINATION PAYMENTS

     In the event of termination of Executive's employment during the Employment
Period, subject to the Employment Agreement, if applicable, all compensation and
benefits shall terminate except as specifically provided in this section.

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8.1  TERMINATION BY THE COMPANY OTHER THAN FOR CAUSE OR BY THE EXECUTIVE FOR
     GOOD REASON

     If during the Employment Period the Company terminates the Executive's
employment other than for Cause or the Executive terminates his employment for
Good Reason, the Executive shall be entitled to:

     A.   receive payment of the following accrued obligation (the "Accrued
          Obligations"):

          1)  the Executive's then current annual base salary through the Date
              of Termination to the extent not therefore paid;

          2)  the product of (x) the Annual Bonus payable with respect to the
              fiscal year in which the Date of Termination occurs and (y) a
              fraction, the numerator of which is the number of days in the
              current fiscal year through the Date of Termination, and the
              denominator of which is 3654; and

          3)  any compensation previously deferred by the Executive (together
              with accrued interest or earnings thereon, if any) and any accrued
              vacation pay which would be payable under the Company's standard
              policy, in each case to the extent not therefore paid;

     B.   for twelve months after the Date of Termination, the Company shall pay
          the Executive's premiums for health insurance benefit continuation for
          Executive and his family members, if applicable, which the Company
          provides to the Executive under the provisions of the federal
          Comprehensive Omnibus Budget Reconciliation Act of 1986, as amended
          ("COBRA") to the extent that the Company (such continued payment is
          hereinafter referred to as "COBRA Continuation"); and

     C.   an amount as severance pay equal to one (1) times the Annual Base
          Salary for the fiscal year in which the Date of Termination occurs;

LESS all amounts payable by the Company to Executive as a result of such
termination under the Employment Agreement.

8.2  TERMINATION FOR CAUSE OR OTHER THAN FOR GOOD REASON

     If during the Employment Period the Executive's employment shall be
terminated by the Company for Cause or by the Executive for other than Good

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Reason, this Agreement shall terminate without further obligation on the part of
the Company to the Executive, other than the Company's obligation to pay the
Executive:

     A.  his Annual Base Salary through the Date of Termination,

     B.  the amount of any compensation previously deferred by the Executive,
         and

     C.  any accrued vacation pay which would be payable under the Company's
         standard policy, in each case to the extent heretofore unpaid;

LESS all amounts payable by the Company to Executive as a result of such
termination under the Employment Agreement.

8.3  EXPIRATION OF TERM

     In the case of a termination of the Executive's employment as a result of
the expiration of the Term of this Agreement, this Agreement shall terminate
without further obligation on the part of the Company to the Executive, other
than the Company's obligation to pay the Executive the Accrued Obligations.

8.4  TERMINATION BECAUSE OF DEATH OR TOTAL DISABILITY

     If during the Employment Period the Executive's employment is terminated by
reason of the Executive's death or Total Disability, this Agreement shall
terminate automatically without further obligation on the part of the Company to
the Executive or his legal representatives under this Agreement, other than the
Company's obligation to pay the Executive the Accrued Obligations (which shall
be paid to the Executive's estate or beneficiary, as applicable in the case of
the Executive's death), and to provide COBRA Continuation.

8.5  PAYMENT SCHEDULE

     All payments of Accrued Obligations, or any portion thereof payable
pursuant to this Section 8, shall be made to the Executive within ten working
days of the Date of Termination.  Any severance payments payable to the
Executive pursuant to Section 8.1C shall be made to the Executive, at the
Company's option, either in the lump sum within ten working days of the Date of
Termination; or in two equal payments, the first of which is made within ten
working days of the Date of Termination and the second of which is made within
six months of the Date of Termination.

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8.6  CAUSE

     For purposes of this Agreement, "Cause" means cause given by the Executive
to the Company and shall include, without limitation, the occurrence of one or
more of the following events:

     A.  A clear refusal to carry out any material lawful duties of the
         Executive or any directions of the Board or senior management of the
         Company, all reasonably consistent with those duties described in
         Section 3.2 hereof;

     B.  Persistent failure to carry out any lawful duties of the Executive
         described in Section 3.2 hereof or any directions of the Board or
         senior management reasonably consistent with those duties herein set
         forth to be performed by the Executive, provided Executive has been
         given reasonable notice and opportunity to correct any such failure;

     C.  Violation by the Executive of a state or federal criminal law involving
         the commission of a crime against the Company or any other criminal act
         involving moral turpitude;

     D.  Current abuse by the Executive of alcohol or controlled substances;
         deception, fraud, misrepresentation or dishonesty by the Executive; or
         any incident materially compromising the Executive's reputation or
         ability to represent the Company with investors, customers or the
         public; or

     E.  Any other material violation of any provision of this Agreement by the
         Executive, subject to the notice and opportunity to cure requirements
         of Section 11.

8.6  GOOD REASON

     For purposes of this Agreement, "Good Reason" means

     A.  The assignment to the Executive of any duties materially inconsistent
         with the Executive's position, authority, duties or responsibilities as
         contemplated by Section 3.2 hereof or any other action by the Company
         which results in a material diminution in such position, authority,
         duties or responsibilities, excluding for this purpose an isolated and
         inadvertent action not taken in bad faith and which is remedied by the
         Company promptly after receipt of notice thereof given by the
         Executive;

     B.  Any failure by the Company to comply with any of the provision of
         Section 5 or Section 6 hereof, other than an isolated and inadvertent
         failure not 

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         taken in bad faith and which is remedied by the Company promptly after
         receipt of notice thereof given by the Executive;

     C.  The Company's requiring the Executive to be based at any office or
         location more than that described in Section 3.3 hereof;

     D.  Any failure by the Company to comply with and satisfy Section 13
         hereof, provided that the Company's successor has received at least ten
         days' prior written notice from the Company or the Executive of the
         requirements of Section 13 hereof; or

     E.  Any other material violation of any provision of this Agreement by the
         Company, subject to the notice and opportunity to cure requirements of
         Section 11.

8.7  EXCESS PARACHUTE LIMITATION

     If either the Company or the Executive receives confirmation from the
Company's independent tax counsel or its certified public accounting firm, or
such other accounting firm retained as independent certified public accountants
for the Company (the "Tax Advisor"), that any payment by the Company to the
Executive under this Agreement or otherwise would be considered to be an "excess
parachute payment" within the meaning of Section 280G of the Internal Revenue
Code of 1986, as amended, or any successor statute then in effect (the "Code"),
then the aggregate payments by the Company pursuant to this Agreement shall be
reduced to the highest amount that may be paid to the Executive by the Company
under this Agreement without having any portion of any amount payable to the
Executive by the Company or a related entity under this agreement or otherwise
treated as such an "excess parachute payment", and, if permitted by applicable
law and without adverse tax consequence, such reduction shall be made to the
last payment due hereunder.  Any payments made by the Company to the Executive
under this Agreement which are later confirmed by the Tax Advisor to be "excess
parachute payments" shall be considered by all parties to have been a loan by
the Company to the Executive, which loan shall be repaid by the Executive upon
demand together with interest calculated at the lowest interest rate authorized
for such loans under the Code without a requirement that further interest be
imputed.

              9.  REPRESENTATIONS, WARRANTIES AND OTHER CONDITIONS

     In order to induce the Company to enter into this Agreement, the Executive
represents and warrants to the Company as follows:

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9.1  HEALTH

     The Executive is in good health and knows of no physical or mental
disability which, with any accommodation which may be required by law and which
places no undue burden on the Company, would prevent him form fulfilling his
obligations hereunder.  The Executive agrees, if the Company requests, to submit
to reasonable periodic medical examinations by a physician or physicians
designated by, paid for and arranged by the Company.  The Executive agrees that
the examination's medical report shall be provided to the Company.

9.2  NO VIOLATION OF OTHER AGREEMENT

     The Executive represents that neither the execution nor the performance of
this Agreement by the Executive will violate or conflict in any way with any
other agreement by which the Executive may be bound.

                    10.  NONDISCLOSURE; RETURN OF MATERIALS

10.1  NONDISCLOSURE

     Except as required by his employment with the Company, the Executive will
not, at any time during the term of employment by the Company, or at any time
thereafter, directly, indirectly or otherwise, use, communicate, disclose,
disseminate, lecture upon or publish articles relating to any confidential,
proprietary or trade secret information without the prior written consent of the
Company.  The Executive understands that the Company will be relying on this
covenant in continuing the Executive's employment, paying him compensation,
granting him any promotions or raises, or entrusting him with any information
which helps the Company compete with others.

10.2  RETURN OF MATERIALS

     All documents, records, notebooks, notes, memoranda, drawings or other
documents made or compiled by the Executive at any time while employed by the
Company, or in his possession, including any and all copies thereof, shall be
the property of the Company and shall be held by the Executive in trust and
solely for the benefit of the Company, and shall be delivered to the Company by
the Executive upon termination of employment or at any other time upon request
by the Company.

                         11.  NOTICE AND CURE OF BREACH

     Whenever a breach of this Agreement by either party is relied upon as
justification for any action taken by other party pursuant to any provision of
this 

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Agreement, other than clause A, B, C, or D of Section 8.6 hereof, before such
action is taken, the party asserting the breach of this Agreement shall give the
other party at least ten days' prior written notice of the existence and the
nature of such breach before taking further action hereunder and shall give the
party purportedly in breach of this Agreement the opportunity to correct such
breach during the ten-day period.

                              12.  FORM OF NOTICE

     Every notice required by the terms of this Agreement shall be given in
writing by serving the same upon the party to whom it was addressed personally
or by registered or certified mail, return receipt requested, at the address set
forth below or at such other address as may hereafter be designated by notice
given in compliance with the terms hereof:


If to the Executive            Ken Tapman

If to the Company              ProCyte Corporation
                               8511 154th Avenue NE, Building A
                               Redmond, WA  98052-3557
                               Attn:  Corporate Secretary

With a copy to                 Perkins Coie
                               1201 Third Avenue, 40th Floor
                               Seattle, WA  98101-3099
                               Attn:  James R. Lisbakken

     or such other address as shall be provided in accordance with the terms
hereof.  Except as set forth in Section 4.4 hereof, if notice is mailed, such
notice shall be effective upon mailing.

                                13.  ASSIGNMENT

     This Agreement is personal to the Executive and shall not be assignable by
the Executive.

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     The Company shall assign to and require any successor (whether direct or
indirect, by purchase, merger, consolidation or otherwise) to all or
substantially all the business and/or assets of the Company to assume expressly
and agree to perform this Agreement in the same manner and to the same extent
that the Company would be required to perform it if no such succession had taken
place.  As used in this Agreement, "Company" shall mean ProCyte Corporation and
any affiliated company or successor to its business and/or assets as aforesaid
which assumes and agrees to perform this Agreement by contract, operation of
law, or otherwise; and as long as such successor assumes and agrees to perform
this Agreement, the termination of Executive's employment by one such entity and
the immediate hiring and continuation of the Executive's employment by the
succeeding entity shall not be deemed to constitute a termination or trigger any
severance obligation under this Agreement.  All the terms and provisions of this
Agreement shall be binding upon and inure to the benefit of and be enforceable
by the parties hereto and their respective successors and permitted assigns.

                                  14.  WAIVERS

     No delay or failure by any party hereto in exercising, protecting or
enforcing any of its rights, titles, interests or remedies hereunder, and no
course of dealing or performance with respect thereto, shall constitute a waiver
thereof.  The express waiver by a party hereto of any right, title, interest or
remedy in a particular instance or circumstance shall not constitute a waiver
thereof in any other instance or circumstance.  All rights and remedies shall be
cumulative and not exclusive of any other rights or remedies.

                           15.  AMENDMENTS IN WRITING

     No amendment, modification, waiver, termination or discharge of any
provision of this Agreement, nor consent to any departure therefrom by either
party hereto, shall in any event be effective unless the same shall be in
writing, specifically identifying this Agreement and the provision intended to
be amended, modified, waived, terminated or discharged and signed by the Company
and the Executive, and each such amendment, modification, waiver, termination or
discharge shall be effective only in the specific instance and for the specific
purpose for which given.  No provision of this Agreement shall be varied,
contradicted or explained by any oral agreement, course of dealing or
performance or any other matter not set forth in an agreement in writing and
signed by the Company and the Executive.

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                              16.  APPLICABLE LAW

     This Agreement shall in all respects, including all matters of
construction, validity and performance, be governed by, and construed and
enforced in accordance with, the laws of the State of Washington, without regard
to any rules governing conflicts of laws.

                       17.  ARBITRATION; ATTORNEY'S FEES

     Except in connection with enforcing Section 7 of this Agreement, for which
legal and equitable remedies may be sought in a court of law, any dispute
arising under this Agreement shall be subject to arbitration.  The arbitration
proceeding shall be conducted in accordance with the Commercial Arbitration
Rules of the American Arbitration Association then in effect, conducted by one
arbitrator either mutually agreed upon or selected in accordance with the AAA
Rules.  The arbitration shall be conducted in King County, Washington under the
jurisdiction of the Seattle office of the American Arbitration Association.  The
arbitrator shall have authority only to interpret and apply the provisions of
this Agreement, and shall have no authority to add to, subtract from, or
otherwise modify the terms of this Agreement.  Any demand for the arbitration
must be made within sixty (60) days of the event(s) giving rise to the claim
that this Agreement has been breached.  The arbitrator's decision shall be final
and binding, and each party agrees to be bound to by arbitrator's award subject
only to an appeal therefrom in accordance with the laws of the State of
Washington.  Either party may obtain judgment upon the arbitrator's award in the
Superior Court of King County, Washington.

     If it becomes necessary to pursue or defend any legal proceeding, whether
in arbitration or court, in order to resolve a dispute arising under this
Agreement, the prevailing party in any such proceeding shall be entitled to
recover its reasonable costs and attorneys' fees.

                               18.  SEVERABILITY

     If any provision of this Agreement shall be held invalid, illegal or
unenforceable in any jurisdiction, for any reason, including, without
limitation, the duration of such provision, its geographical scope or the extent
of the activities prohibited or required by it, then, to the full extent
permitted by law:

     A.  all other provisions hereof shall remain in full force and effect in
         such jurisdiction and shall be liberally construed in order to carry
         out the intent of the parties hereto as nearly as may be possible,

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     B.  such invalidity, illegality or unenforceability shall not affect the
         validity, legality or enforceability of any other provision hereof, and

     C.  any court or arbitrator having jurisdiction thereover shall have the
         power to reform such provision to the extent necessary for such
         provision to be enforceable under applicable law.

                             19.  ENTIRE AGREEMENT

     This Agreement on and as of the date hereof and the Employment Agreement
constitutes the entire agreement between the Company and the Executive with
respect to the subject matter hereof and all prior or contemporaneous oral or
written communications, understandings or agreements between the Company and the
Executive with respect to such subject matter are hereby superseded and
nullified in their entireties, except that the Proprietary Information and
Invention Agreement between the Executive and the Company shall continue in full
force and effect to the extent not superseded by Section 10 hereof.

                                20.  WITHHOLDING

     The Company may withhold from any amounts payable under this Agreement such
federal, state or local taxes as shall be required to be withheld pursuant to
any applicable law or regulation.

                               21.  COUNTERPARTS

     This Agreement may be executed in counterparts, each of which counterpart
shall be deemed an original, but all of which together shall constitute on e and
the same instrument.

     IN WITNESS WHEREOF,  the parties have executed and entered into this
Agreement effective on the date first set forth above.


PROCYTE CORPORATION                    KEN TAPMAN


By:  /s/ John F. Clifford              By:  /s/ Ken Tapman
    --------------------------             --------------------------
Name: John F. Clifford                 Name:  /s/ Ken Tapman
      ------------------------               ------------------------
Title: Chief Executive Officer         Title: 
       -----------------------                -----------------------

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