A QUANTITATIVE OBSERVATIONAL STUDY WAS MADE OF POLICE IN A CITY OF MORE THAN 500,000, IN TWO SUBURBS OF THAT CITY, AND IN TWO OTHER JURISDICTIONS AND AN EASTERN TOWNSHIP SERVING AN URBAN AREA. OBSERVERS, TRAINED OVER 3 MONTHS, TRAVELED WITH POLICE ON A RANDOM-TIME SAMPLE BASIS RECORDING DATA ON ELECTRONIC CODING EQUIPMENT. PROBLEMS PATROL OFFICERS ENCOUNTERED IN EACH OF THESE FIVE DEPARTMENTS WERE CODED INTO ONE OF SIX CATEGORIES: PUBLIC INFORMATION (CALLS ABOUT A CRIMINAL INCIDENT, MISSING PERSON, ETC.); SERVICE CALLS (ACCIDENTS, LOCK-OUTS, ASSISTANCE); ORDER MAINTENANCE (DISTURBANCE OF THE PEACE); LAW ENFORCEMENT (SERIOUS OFFENSES OR CRIMES); TRAFFIC; AND OTHER (MISCELLANEOUS PROBLEMS). RESULTS SHOWED THAT THE MOST FREQUENT TYPE OF ACTIVITY OVERALL WAS LAW ENFORCEMENT. URBAN POLICE DEALT WITH MORE CRIMINAL INCIDENTS THAN DID SUBURBAN AND STATE POLICE. ORDER MAINTENANCE ALSO OCCUPIED A SIGNIFICANT PROPORTION OF POLICE PATROL TIME. MOVING AND PARKING VIOLATIONS WERE THE THIRD MOST FREQUENT PROBLEM AND WERE ESPECIALLY HEAVY IN SUBURBAN POLICE PATROLS. SERVICE ENCOUNTERS, THE FOURTH MOST FREQUENT TYPE OF ACTIVITY, WERE NEARLY EQUAL IN ALL DEPARTMENTS STUDIED. INFORMATION-GATHERING ACTIVITIES WERE INFREQUENT IN ALL DEPARTMENTS. URBAN DEPARTMENTS WERE MORE FREQUENTLY INVOLVED IN CRIMINAL INCIDENTS, AND DEPARTMENTAL POLICIES SOMETIMES DIFFERED. ALL DEPARTMENTS WERE HIGHLY DEPENDENT ON CITIZEN INPUT (CITIZEN REPORTS OF CRIMINAL INCIDENTS). IT IS SUGGESTED THAT ROUTINE PATROL DOES NOT HAVE A DETERRENT EFFECT ON CRIME AND THAT A REVIEW OF DEPARTMENTAL POLICES IN THE AREAS OF TRAFFIC VIOLATION AND PROVISION OF SERVICES TO CITIZENS IS SUGGESTED. TABULAR DATA AND NOTES ARE INCLUDED. (MJW)