MANY PHYSICAL CONDITIONS PRODUCE SYMPTOMS SIMILAR TO MENTAL ILLNESS, INCLUDING DIABETES, HEAD INJURIES, HIGH BLOOD PRESSURE, AND EPILEPSY AND OTHER CONDITIONS ASSOCIATED WITH CONVULSIONS. THE IMPORTANCE OF CAREFUL OBSERVATION DURING THE FIRST HOURS AFTER ARREST AND OF MEDICAL EXAMINATION AS SOON AS POSSIBLE IS EMPHASIZED. METHODS OF IDENTIFYING MENTALLY ILL PERSONS, TECHNIQUES FOR HANDLING THEM QUIETLY AND FIRMLY, AND TACTICS USEFUL IN CASES OF VIOLENCE ARE GIVEN. DEPRESSION OFTEN LEADS TO SUICIDE. SUICIDE PREVENTION IS DISCUSSED. THE SPECIAL PROBLEMS OF MENTAL RETARDATION, ELDERLY PERSONS, ALCOHOLICS, AND VARIOUS FORMS OF DRUG ADDICTION ARE DISCUSSED WITH SUGGESTIONS FOR HANDLING THEM. IF JAIL FACILITIES CANNOT PROVIDE EMERGENCY CARE OR SUITABLE LONG-TERM CARE, ARRANGEMENTS FOR TRANSPORTATION TO AN APPROPRIATE FACILITY SHOULD BE STANDARD OPERATING PROCEDURE. LONG-TERM JAIL PROCEDURES FOR THOSE WITH MENTAL ILLNESS NEED TO BE CAREFULLY DEFINED. SUGGESTIONS ARE MADE FOR APPROPRIATE HOUSING AND WORK ASSIGNMENTS, OBSERVATION PROCEDURES, AND GUIDELINES FOR CALLING FOR HELP. SPECIFICATIONS FOR A PSYCHIATRIC/SUICIDAL OBSERVATION ROOM ARE ALSO GIVEN.