FROM APRIL 1, 1976, TO SEPTEMBER 30, 1976, A CRIME PREVENTION PROGRAM USING A PATROL-ORIENTED, TARGET-HARDENING STRATEGY WAS IMPLEMENTED IN THE UNINCORPORATED AREA OF ST. LOUIS COUNTY. THIS AREA COVERS ABOUT 325 SQUARE MILES AND INCLUDES 348,431 PEOPLE. PATROL OFFICERS WROTE DOWN THE ADDRESS OF ANY HOME WITH AN OPEN GARAGE WHEN NO RESIDENT APPEARED TO BE HOME. A LETTER WAS THEN SENT ALERTING THE HOMEOWNER OF THE DANGER OF THEFT. IN CASES IN WHICH A LETTER HAD ALREADY BEEN SENT, A MORE STRONGLY WORDED LETTER, ALONG WITH A BROCHURE, WAS SENT OUT. NO OTHER CONTACT WAS MADE. RESEARCH HAD PREVIOUSLY SHOWN THAT IN THIS AREA GARAGE BURGLARIES WERE A WORSENING PROBLEM, THE CRIME WAS RELATED TO THE WARMER MONTHS OF THE YEAR, AND A CLOSED GARAGE DOOR MIGHT HAVE PREVENTED THE CRIME. AT THE END OF THE PILOT PROGRAM PERIOD, GARAGE BURGLARIES HAD DECREASED 32 PERCENT WHEN COMPARED WITH THE SAME SEASON IN 1975; HOWEVER, HOME BURGLARIES INCREASED 7 PERCENT. TO DETERMINE THE IMPACT OF THE PILOT PROGRAM ON THIS 32-PERCENT DECREASE, A POLICY ANALYSIS WAS USED BY RESEARCHERS. THIS QUASI-EXPERIMENTAL ANALYSIS WAS APPLIED TO 84 SUBPRECINCT AREAS IN THE TEST ZONE (TWO PRECINCTS). THE THREE REMAINING UNTREATED PRECINCTS WERE USED AS A CONTROL AREA. IN THE TEST ZONE, RESEARCHERS MEASURED THE LETTER SATURATION FOR EACH SUBPRECINCT AREA, THE TOTAL NUMBER OF INITIAL LETTERS, AND THE TOTAL NUMBER OF SECONDARY LETTERS DIVIDED BY THE NUMBER OF HOUSES. THEY ALSO COMPUTED THE CHANGES IN UNLAWFUL ENTRY GARAGE BURGLARIES FROM THE PREPROGRAM PERIOD TO THE PROGRAM PERIOD. RESULTS INDICATED THAT THE SATURATION LEVELS OF INITIAL LETTERS WERE NOT STRONGLY RELATED TO THE CHANGE IN UNLAWFUL ENTRY GARAGE BURGLARIES, AND THAT THE SATURATION LEVELS OF SECONDARY LETTERS WERE NOT RELATED AT ALL TO CHANGES IN UNLAWFUL ENTRY GARAGE BURGLARIES. MOST IMPORTANT OF ALL, TABULATED DATA FOR THE TEST AREA AND THAT FOR THE CONTROL AREA REVEALED VERY LITTLE DIFFERENCE. THE VALIDITY OF THE STUDY WAS THREATENED BY THE POSSIBILITY OF UNREPORTED CRIME, THE ABSENCE OF A VICTIMIZATION SURVEY BEFORE AND AFTER THE PROGRAM WAS STARTED, POSSIBLE VARIATIONS IN REPORTING PRACTICES, AND THE POSSIBILITY OF A REGRESSION OVER A PERIOD OF TIME. AVAILABLE DATA INDICATE THAT THE PROGRAM HAD FAILED, AND THE FAILURE COULD NOT BE ATTIBUTED TO VALIDITY PROBLEMS, AND NO DEFINITIVE REASON FOR FAILURE COULD BE FOUND. THE MOST PLAUSIBLE EXPLANATION IS THAT THE LETTERS DID NOT MOTIVATE HOMEOWNERS SUFFICIENTLY TO CHANGE THEIR HABITS, BUT THIS HYPOTHESIS WAS NOT TESTED. CHARTS, TABLES, AND A BIBLIOGRAPHY ARE PROVIDED. (FCW) BIBLIOGRAPHY ARE PROVIDED. (FCW)