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                                                                   EXHIBIT 10.15



                                 ENDOCARE, INC.

                              CONSULTING AGREEMENT


        This Consulting Agreement is entered into as of May 27, 1997 between Bob
Byrnes ("Consultant") and ENDOCARE, INC., a Delaware corporation
("Corporation"). In consideration of the mutual covenants set forth in this
Agreement, the parties agree as follows:

1.      TERM OF RETENTION AS CONSULTANT

        Upon the terms and conditions set forth in this Agreement, Corporation
hereby agrees to retain Consultant, and Consultant agrees to act, as a
consultant to Corporation. During the term of this Agreement, Consultant agrees
to perform the duties set forth in Exhibit A to this Agreement. Within 60 days
of signing this initial agreement, the parties agree to use their best efforts
to sign a long term agreement.

2.      COMPENSATION

        For his/her services to Corporation under Section 1 during the term of
this Agreement, Consultant shall receive from Corporation a monthly consulting
fee of $15,000.00 per month, payable at the first of each month.

3.      EXPENSES

        Corporation shall reimburse Consultant for reasonable out-f-pocket
expenses incurred by Consultant in connection with Corporation's business, but
only if the incurring of any such expenses is approved in writing by an
executive officer of Corporation and Consultant provides Corporation with such
substantiating receipts or other documentation as Corporation may reasonably
require.

4.      TERM

        The term of this Agreement shall begin on the date set forth in the
first paragraph and shall continue until terminated in accordance with this
Section. Either party may terminate this Agreement, at such party's discretion
without cause, by giving at least seven (7) days prior written notice of the
termination to the other party. The termination of this Agreement pursuant to
this Section shall not release either party from any accrued obligation to pay
any sum to the other party (whether then or thereafter payable) or operate to
discharge any liability incurred prior to the termination date. In addition, the
obligations under the following sections shall survive the termination of this
Agreement.

5.      CONFIDENTIAL INFORMATION

        (a) As used in this Agreement, the term "Confidential Information"
refers to any and all valuable information of a confidential, proprietary or
secret nature related to the present or future business of Corporation, the
research and development activities of Corporation or the business



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of any customer of or supplier or contractor to Corporation. Confidential
Information is to be broadly construed and includes, without limitation: (i)
information disclosed by Corporation or its customers, suppliers or contractors
("together, "Contractors") to Consultant in the course of his retention by
Corporation as well as information developed or learned by Consultant during the
course of his retention; (ii) information that has or could have commercial
value or other utility in the business in which Corporation or its Contractors
are engaged or contemplate being engaged; (iii) information of which the
unauthorized disclosure could be detrimental to the interests of Corporation or
its Contractors, whether or not such information is identified as Confidential
Information by Corporation or its Contractors; and (iv) trade secrets,
processes, formulas, data, source code, know-how, improvements, inventions,
techniques, test results, specifications, costs and pricing data, employee
information, terms of Corporation's agreements, production and marketing plans
and strategies, and information concerning Corporation's Contractors.

        (b) Employee acknowledges that the Confidential Information is a
valuable and unique asset of Corporation, and Consultant agrees at all times
during the period of his retention by Corporation and thereafter to keep in
confidence and trust all Confidential Information. Consultant agrees that during
the period of his retention by Corporation and thereafter he will not directly
or indirectly use or exploit the Confidential Information other than in the
course of performing duties as a consultant of or other contractor to
Corporation, nor will Consultant directly or indirectly disclose any
Confidential Information to any person or entity, except in the course of
performing his duties to Corporation with the consent of Corporation's executive
officers. Consultant will abide by Corporation's policies and regulations, as
established from time to time, for the protection of its Confidential
Information. Consultant agrees to use his best efforts to ensure that
Corporation's confidential information, and any records or documents containing
such information, will not be exposed to theft, embezzlement or unauthorized
reproduction or disclosure.

6.      COMPANY OWNERSHIP OF INNOVATIONS

        (a) As used in the Agreement, "Developments" means all inventions,
discoveries, written or printed materials, trade secrets, designs, techniques,
know-how, data or other technical developments which Consultant makes,
conceives, reduces to practice or learns of, either individually or jointly with
others, during the term of this Agreement, and which are related to or useful in
the business of Corporation or result from Consultant's retention by Corporation
or from the use of premises owned, leased or otherwise use or acquired by
Corporation.

        (b) Subject to the terms of this Agreement, Consultant agrees that any
and all Developments are and will be the exclusive property of Corporation.
Consultant hereby assigns to Corporation all right, title and interest
Consultant may have or may acquire in and to all Developments. Consultant shall
execute any assignments to Corporation or other documents requested by
Corporation to evidence such assignment or Corporation's ownership of all such
Developments and otherwise agrees to cooperate fully with and aid Corporation in
establishing, enforcing and disposing of Corporation's patent and other
proprietary rights with respect to all Developments. In the event Corporation is
unable to secure Consultant's signature on any




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document necessary to apply for, prosecute, obtain or enforce any patent,
copyright or other right or protection relating to any Development, whether due
to mental or physical incapacity or any other cause, Consultant hereby
irrevocably designates and appoints Corporation and each of its duly authorized
officers as his agent and attorney-in-fact, to act for and in his behalf and
stead to execute and file and such document and to do all other lawfully
permitted acts to further the prosecution, issuance and enforcement of such
patents, copyrights or other rights or protections with the same force and
effect as if executed and delivered by Consultant.

        (c) Except with respect to inventions which are to be assigned to or
owned by the United States under contracts between Corporation and departments
or agencies of the United States, the foregoing assignment to Corporation of
Developments will not apply to any invention that Consultant develops entirely
on his own time without the using Corporation's equipment, supplies, facilities
or trade secret information, except for those inventions that either: (i) relate
at the time of conception or reduction to practice of the invention to
Corporation's business or to its actual or demonstrably anticipated research or
development; or (ii) result from any work performed by Consultant for
Corporation.

        (d) Consultant will make full and prompt disclosure to Corporation of
all Developments made, conceived, reduced to practice or learned by Consultant,
either individually or jointly with others, during the term of this Agreement.
Consultant shall attach to this Agreement a schedule contain a complete listing
of any Developments relevant to his retention by Corporation that were made,
conceived or first reduced to practice by Consultant alone or jointly with
others prior to his retention by Corporation, or which are covered by the
exclusion set forth in (c) above, and that Consultant desires to remove from the
operation of this Agreement. Corporation agrees to hold any disclosure in such
schedule in confidence.

7.      RETURN OF COMPANY MATERIALS

        Upon the termination of this Agreement for any reason, Consultant agrees
promptly and without request to deliver to Corporation all originals and copies
of notebooks, documents, reports, files, samples, mailing lists, computer
programs and other records and data which are then in Consultant's possession or
under his control and which pertain to his retention by Corporation or include
Confidential Information or Developments, and to return to Corporation any other
tangible personal property owned by Corporation, unless such return is waived in
writing by Corporation. Provided such retention is disclosed to Corporation and
subject to the Consultant's confidentiality obligations, Consultant may retain
copies of any such records required to be retained by Consultant to satisfy tax
reporting or other legal requirements. Consultant recognizes that the
unauthorized taking of any of Corporation's trade secrets is a crime and could
also result in civil liability to Corporation.

8.      COMPETITION

        Consultant agrees that, during the term of this Agreement, he will not,
except. for Corporation or with the written consent of an executive officer of
Corporation, engage or have an interest, directly or indirectly, in any other
business or venture which would interfere with the




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performance of his obligations to Corporation or which competes with any
material part of Corporation's business. However, this restriction shall not
prevent Consultant from passively owning or investing in (a) any shares or other
assets which he owns on the date of this Agreement and are listed on a schedule
attached to this Agreement or (b) less than one percent (1%) of the outstanding
shares of a corporation which are publicly traded.

9.      REMEDIES

        Consultant acknowledges that his services under this Agreement and his
agreements in Sections 5-8 are of a special, unique, unusual, extraordinary
and/or intellectual character, which give them particular value, that his
violation of this Agreement will constitute a material breach of trust and
confidence and may be an invasion of privacy, that the breach by him of his
agreements set forth in this Agreement could not reasonably or adequately be
compensated in damages in an action at law, and that Corporation shall be
entitled to injunctive relief for such a breach. Such relief may include, but
shall not be limited to, an injunction restraining Consultant from rendering any
service or engaging in any activity which breaches or would violate this
Agreement. However, no remedy conferred by any of the specific provisions of
this Agreement is intended to be exclusive of any other remedy, and each and.
every remedy shall be cumulative and shall be in addition to every other remedy
existing at law or in equity. The election of any one or more remedies by
Corporation shall not constitute a waiver of its rights to pursue other
available remedies.

10.     CONFLICTING AGREEMENTS

        Consultant represents that his retention by Corporation under this
Agreement and related actions have not breached, and will not breach, any
covenant to keep in confidence proprietary information or any other agreement
with a third party. Consultant has not entered into, and agrees that he will not
enter into, any agreement either written or oral in conflict with this
Agreement.

11.     MISCELLANEOUS

        (a) GOVERNING LAW

            All questions with respect to the construction of this Agreement and
the rights and liabilities of the parties shall be governed by the laws of the
State of California, excluding its conflict of laws rules.

        (b) SUCCESSORS AND ASSIGNS

            This Agreement shall inure to the benefit of and be binding upon the
parties and their respective successors and assigns. Consultant may not assign
or otherwise transfer any of his rights or obligations under this Agreement
without Corporation's prior written consent and any such transfer in violation
of this paragraph shall be void.




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        (c) ENTIRE AGREEMENT

            This Agreement contains all of the terms and conditions agreed upon
by the parties, and supersedes any prior agreements or understandings, with
respect to the subject matter of this Agreement.

        (d) AMENDMENT OR MODIFICATION OF AGREEMENT

            This Agreement may be modified, altered or amended only by the
written agreement of both the parties.

        (e) ATTORNEYS' FEES AND COSTS

            In any legal proceeding to enforce or interpret the terms of this
Agreement, the prevailing party shall be entitled to reasonable attorney's fees
and costs and necessary disbursements in addition to any other relief to which
it or he may be entitled.

        (f) COUNTERPARTS

            This Agreement may be executed in one or more counterparts, each of
which shall be a valid original agreement.

        (g) SEVERABILITY

            If any provision of this Agreement or its application to any person
or circumstance is held invalid or unenforceable to any extent, the remainder of
this Agreement and its other application shall not be affected and shall be
enforceable to the fullest extent permitted by law.

        (h) FURTHER ACTIONS

            Each party agrees to execute and deliver any further documents and
to do any additional acts reasonably required to carry out the terms of this
Agreement.

        (i) WAIVERS

            Any provision of this Agreement may be waived at any time by the
party entitled to the benefit thereof by a written instrument executed by the
party or by a duly authorized officer of the party. No waiver of any of the
provisions of this Agreement will be deemed, or will constitute, a waiver of any
other provision, whether or not similar, nor will any waiver constitute a
continuing waiver.

        (j) NOTICES

            Any notice or other communication to a party provided for in this
Agreement shall be deemed to have been duly given if delivered personally in
writing to the party or on the




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date of its delivery, in writing addressed to the parry, at such party's address
determined in accordance with this paragraph. The address of Consultant shall
be: 6037 Birdcage Court, Orange, CA 92869. The address of Corporation shall be:
7 Studebaker, Irvine, California 9261 S. Either party may change its or his
address for purposes of this Agreement by a notice given to the other party in
accordance with this paragraph.

        (k) INDEPENDENT CONTRACTOR

            Consultant is retained by Corporation only for the purposes and to
the extent set forth in this Agreement, and his relationship to Corporation
shall, during the term of this Agreement, be that of an independent contractor.
Consultant shall not be considered as having employee status or as being
entitled to participate in any plans, arrangements or distributions by
Corporation pertaining to any pension, profit sharing or similar benefits for
Corporation's employees. Corporation shall not withhold any of Consultant's
compensation payments for income tax purposes and shall not have any obligations
with regard to Social Security payments for Consultant, insurance or workers'
compensation coverage for Consultant, or any similar items. Nothing contained in
this Agreement shall be deemed or construed to constitute a relationship of
partnership, joint venture, principal and agent, employer and employee,
franchisor and franchisee, or any other association between the parties.

        (1) JURISDICTION

            Each party to this Agreement agrees that an action or proceeding to
determine or enforce any rights or obligations under this Agreement may be
brought in the courts of the State of California in and for the Counties of
Orange and Los Angeles. Each party consents to the jurisdiction of such courts
over such party for purposes of any such action or proceeding.

        (m) GENDER

            Where required by the context, the masculine gender of pronouns
shall be deemed to include the feminine or the neuter.




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EXECUTED at Irvine, California as of the date first written above.



                                        CORPORATION:

                                        ENDOCARE, INC.,
                                        a Delaware corporation


                                        By:    /s/ PAUL MIKUS
                                            ------------------------------------
                                               Paul Mikus, President


                                        CONSULTANT:


                                               /s/ ROBERT F. BYRNES
                                        ----------------------------------------
                                               Signature

                                        ----------------------------------------
                                               Robert F. Byrnes
                                               Printed Name




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                                    EXHIBIT A

                                     DUTIES


To provide consulting services with regard to sales and marketing and strategic
alliance planning.






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