Exhibit 5


                                  May 20, 2002




Criticare  Systems,  Inc.
29025  Crossroads  Circle
Waukesha,  Wisconsin  53186

Gentlemen:

     We are providing this opinion in connection with the Registration Statement
of  Criticare Systems, Inc., a Delaware corporation (the "Company"), on Form S-8
(the  "Registration  Statement"),  filed  under  the  Securities Act of 1933, as
amended  (the  "Act"), with respect to the proposed sale by the Company of up to
2,050,000  shares  of  Company  common  stock,  $.04  par  value  per share (the
"Shares"),  pursuant  to  the  provisions  of  the  Criticare Systems, Inc. 1992
Employee  Stock  Option  Plan  (the  "Plan").

     We have examined (1) the Registration Statement, (2) the Company's Restated
Certificate  of Incorporation and By-Laws, as amended to date, (3) the Plan, (4)
the  corporate proceedings relating to the adoption of the Plan, the issuance of
the Shares and the organization of the Company, and (5) such other documents and
records  as  we  have  deemed  necessary  in  order  to render this opinion.  In
rendering  this  opinion,  we  have  relied  as  to  certain  factual matters on
certificates  of  officers  of  the  Company  and  of  state  officials.

     Based upon the foregoing, it is our opinion that the Shares, when issued as
and  for  the  consideration  contemplated by the Registration Statement and the
Plan,  will  be  validly  issued,  fully  paid and nonassessable by the Company,
subject  to  the  personal  liability  which  may  be imposed on shareholders by
Section  180.0622(2)(b) of the Wisconsin Business Corporation Law, as judicially
interpreted,  for  debts  owing  to  employees  for  services performed, but not
exceeding  six  months  service  in  any  one  case.



     We  consent to the filing of this opinion as an Exhibit to the Registration
Statement.  In giving this consent, we do not admit that we are "experts" within
the  meaning  of  section  11 of the Act, or that we come within the category of
persons  whose  consent  is  required  by  section  7  of  the  Act.

                                           Yours  very  truly,

                                           REINHART  BOERNER  VAN  DEUREN  s.c.

                                           BY     /s/  Benjamin  G.  Lombard