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                                                                 EXHIBIT 10.13


                         PROMISSORY NOTE BY AND BETWEEN

                               CHARLES A. LAVERTY
                                       AND
                             UROHEALTH SYSTEMS, INC.


Principal Amount: $550,000                             DATED: NOVEMBER 27, 1996

         FOR VALUE RECEIVED, Charles A. Laverty ("MAKER"), does hereby promise
to pay to UROHEALTH Systems, Inc. ("HOLDER"), in lawful money of the United
States and in immediately available funds, the principal amount of five hundred
fifty thousand dollars ($550,000), with interest compounding annually thereon.
Interest shall accrue at a per annum rate equal to six and two one-hundredths
percent (6.02%).

         The balance of the principal amount of the Note outstanding and all
accrued and unpaid interest thereof shall be due and payable in full upon the
earlier of (a) November 25, 1999 or (b) within thirty (30) days of the
termination for any reason of that certain Employment Agreement by and between
Maker and Holder in effect as of the date hereof.

         Payment shall be delivered to Holder at the address as set forth below,
or at such other address as designated by Holder.

         The following shall constitute an Event of Default:

         (i)   A default in payment by Maker to Holder of any payment due
               hereunder, when due and payable which continues for five (5) days
               after any such payment is due; or

         (ii)  Maker shall be adjudicated a bankrupt, or a decree or order
               approving as properly filed a petition or answer asking 
               reorganization of Maker under the federal bankruptcy laws, as now
               or hereafter amended, or under the laws of any state, shall be 
               entered, and any such decree, judgment, or order shall not have
               been vacated, stayed, or set aside within ninety (90) days from
               the date of its entry or granting; or

         (iii) Maker shall file, or admit the jurisdiction of the court and the
               material allegations contained in, any petition in bankruptcy or
               any petition pursuant to, or purporting to be pursuant to, any 
               current or future acts of Congress on the subject of bankruptcies
               or any amendments to such acts, or Maker shall institute any 
               proceedings, or Maker shall give its consent to the institution
               of any proceedings, for any relief of Maker under any bankruptcy
               or insolvency laws, or any laws relating to the relief of 
               debtors, readjustment of indebtedness, reorganizations, 
               arrangements, compositions, or extensions; or


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         (iv)  Maker shall make any assignment for the benefit of creditors or
               shall apply for a consent to the appointment of a receiver for 
               Maker or any of the property of Maker; or

         (v)   A decree or order appointing a receiver of the property of Maker
               shall be made and the decree or order has not been vacated, 
               stayed, or set aside within ninety (90) days from the date of its
               entry or granting.

         Upon the occurrence of an Event of Default, the entire outstanding
principal balance together with accrued interest hereunder shall, at the option
of Holder, become immediately due and payable and Holder shall thereupon have
all rights and remedies provided hereunder, in any other agreement between Maker
and Holder, or otherwise available at law or in equity.

         Maker waives presentment, demand for payment, notice of dishonor, and
all other notices or demands in connection with the delivery, acceptance,
performance, or default of this Note.

         Nothing herein contained, nor any transaction related hereto, shall be
construed or so operate as to require Maker, or any other person liable for
repayment of same, to pay interest at a greater rate than is now lawful in such
case to contract for, or to make any payment, or to do any act contract to law.
Should any interest or other charges paid by Maker, or parties liable for the
payment of this Note, result in the computation or earning of interest in excess
of the maximum rate of interest which is legally permitted under the laws of the
applicable jurisdiction, then any and all excess shall be and the same is hereby
waived by the Holder, and any and all such excess shall be automatically
credited against and in reduction of the balance due under this indebtedness,
and the portion of said excess which exceeds the balance due under this
indebtedness shall be paid by the Holder here for the Maker and parties liable
for the payment of this Note.

         All notices, requests, demands, and other communications provided for
hereunder shall be in writing and shall be deemed to have been duly given if (i)
delivered in person; (ii) given by prepaid telex or telegram, or by facsimile or
other instantaneous electronic transmission device; (iii) sent by Federal
Express or other nationally recognized overnight delivery service, charges paid
by the sender, or (iv) deposited in the United States mail, first class,
registered or certified, return receipt requested, with proper postage prepaid,
as follows:

                           If to Maker:

                           2230 North Euclid Avenue
                           Upland, CA 91784
                           Attn: President


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                           If to Holder:

                           Suite 100
                           5 Civic Plaza
                           Newport Beach, CA  92660
                           Attn: President

         Notices given pursuant to (I), (II), and (III) above shall be deemed
received and effective upon receipt by the addressee thereof. Notices given
pursuant to Section (iv) above shall be deemed received and effective three (3)
days after the date deposited in the mail.

         In the event of a dispute between the parties arising from this Note,
the prevailing party shall be entitled to recover reasonable attorney's fees and
cost of the suit.

         This note shall be governed by the laws of the State of California.


                                         CHARLES A. LAVERTY


                                         /s/ CHARLES A. LAVERTY
                                         ----------------------------
                                             Signature


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