MANY INDIVIDUALS WHO PASS THROUGH COUNTY JAILS ARE IN NEED OF MENTAL HEALTH INTERVENTION. TODAY, THERE ARE BETWEEN 15,000 AND 41,000 JAILS IN THE UNITED STATES WHICH VARY GREATLY IN SIZE AND QUALITY. THE TYPICAL JAIL IS RUN BY THE SHERIFF AND HIS STAFF. JAILS DETAIN THREE GENERAL GROUPS OF PERSONS: THOSE AWAITING TRIAL, THOSE AWAITING SENTENCING, AND THOSE SERVING SENTENCES. THE LARGEST GROUP IS COMPRISED OF CHRONIC OFFENDERS. CLEARLY, THE VAST MAJORITY OF PERSONS WHO ARE JAILED ARE EXHIBITING MALADAPTIVE BEHAVIOR. IN VIEW OF THIS FACT, IT APPEARS THAT THERE IS A LOGICAL BASIS FOR HOSPITAL AND MENTAL HEALTH CENTER INVOLVEMENT IN LOCAL JAILS. JAIL MUST BE REGARDED AS A COMMUNITY AGENCY THAT DEALS WITH A LARGE NUMBER OF COMMUNITY RESIDENTS. TEN TIMES MORE OFFENDERS ARE SENTENCED TO JAIL THAN TO PRISON, OSTENSIBLY FOR THE PURPOSE OF CHANGING THEIR BEHAVIOR. HOWEVER, MOST JAILS ARE MERELY CUSTODIAL INSTITUTIONS EMPLOYING NO TREATMENT STAFF. IN CONTRAST TO MOST JAILS, THE SALT LAKE COUNTY JAIL OFFERS MENTAL HEALTH SERVICES TO DETAINEES. ORIGINALLY THE SERVICES WERE OFFERED ON A CRISIS BASIS AND TYPICALLY INVOLVED HOSPITALIZATION. THE PROGRAM HAS EXPANDED, HOWEVER, AND NOW INCLUDES A WIDE RANGE OF SERVICES. MANY FORMS OF TREATMENT HAVE BEEN USED INCLUDING INDIVIDUAL PSYCHOTHERAPY, FAMILY THERAPY, AND GROUP THERAPY. RECREATIONAL AND EDUCATIONAL SERVICES ARE ALSO OFFERED. REFERRING AGENCIES, JAIL STAFF, AND INMATES FEEL THAT MENTAL HEALTH EVALUATION OR TREATMENT, OR BOTH, IS BENEFICIAL. COMMUNITY MENTAL HEALTH CENTERS AND COMMUNITY HOSPITALS MUST TAKE AN ACTIVE ROLE IN ADDRESSING THE PROBLEMS OF THE JAIL POPULATION. REFERENCES ARE INCLUDED IN THE ARTICLE. (LWM)