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                                 EXHIBIT 10.12







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                                   AMENDMENT


     This is an Amendment, dated March 14, 1997, to an Employment Agreement
dated March 30, 1987 (the "Agreement"), by and between CRITICARE SYSTEMS, INC.,
a Delaware corporation ("Criticare"), and GERHARD J. VON DER RUHR ("Employee").

     1. The Agreement is hereby amended to delete section 8 thereof, to delete
the phrase "subject to the terms of section 8 of this Agreement" as it appears
in sections 6(a) and 6(b) of the Agreement, and to add a new section 5(d) to
read in its entirety:

     (d) Termination Following a Change in Control.  "Change in Control" shall
mean a sale or other transfer not in the ordinary course of business of all or
substantially all of Criticare's assets or a transaction, or series of related
transactions, the effect of which is to cause more than 50% of Criticare's
issued and outstanding voting capital stock to be beneficially owned by one
person or entity or a group of related or affiliated persons or entities.
Notwithstanding any of the other provisions of this section 5, after 6
months following a Change in Control, if Employee's employment terminates for
any reason, whether such termination is initiated by Employee or Criticare (and
regardless of the existence or lack of Cause), Employee (or if Employee dies,
his heirs or beneficiaries) will be entitled to receive and Criticare will pay
and provide his then Base Salary and the fringe benefits described in sections
4(c)(i), (ii) and (iii), at the levels then in effect, for a period of one year
after the date of such termination and the group insurance described in section
5(a) until he reaches age 65.

     2. The Agreement is hereby amended to delete section 4(c) thereof and to
add a new section 4(c) to read in its entirety:

     (c) Fringe Benefits.

     (i) Group Health, Dental and Life Insurance.  Employee will be eligible to
participate in Criticare's group health, dental and life insurance programs on
the same terms and conditions as are available to other employees of Criticare
generally.

     (ii) Automobile.  Criticare will provide Employee will full use of an
automobile owned or leased by Criticare for use in carrying out his duties for
both Criticare and for use in such additional personal business as Employee may
deem appropriate.  Criticare agrees to provide adequate insurance



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for the automobile and occupants and to pay all maintenance and operating costs
appropriate or necessary to maintain such automobile in prime operating
condition.

     (iii) Split-Dollar Life Policy.  Criticare will continue in force and pay
the premiums on the $2,000,000 life insurance policies currently in effect on
Employee's life.

     (iv) Vacation.  Employee will be entitled to receive paid vacations
annually according to the vacation policy established by Criticare.  Such
vacation shall be taken at such times and in such intervals as are mutually
acceptable to Employee and Criticare.

     3. The Agreement in all other respects is not amended but remains
unchanged and the parties thereto continue to be legally bound by the
Agreement, as amended hereby.

                                        CRITICARE SYSTEMS, INC.

                                        BY /s/ Richard J. Osowski
                                          ----------------------------- 
                                              Richard J. Osowski,
                                             Vice President-Finance

                                        /s/ Gerhard J. Von der Ruhr
                                        -------------------------------
                                            Gerhard J. Von der Ruhr














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