THE INVESTIGATORS REVIEWED ANNUAL SAN ANTONIO POLICE DEPARTMENT REPORTS OVER EACH OF 10 YEARS AND COMPUTED TOTALS FOR PART I OFFENSES, BURGLARIES, AND THEFTS. AFTER OBTAINING POPULATION ESTIMATES FOR EACH YEAR, THEY COMPUTED ANNUAL RATES OF THESE OFFENSES PER 1,000 POPULATION. NUMBERS OF HEROIN USERS IN INSTITUTIONAL TREATMENT OR MAINTAINED ON METHADONE WERE ALSO COMPUTED PER 100,000 POPULATION. THE RATE OF PART I OFFENSES INCREASED EVERY YEAR FROM 1965 THROUGH 1969, DECREASED OVER THE NEXT 4 YEARS, AND TURNED UPWARD IN 1974. CHANGE IN THE THEFT RATE ACCOUNTED FOR MOST OF THE CHANGE IN THE PART I OFFENSES RATE. THE BURGLARY RATE ROSE SLIGHTLY FROM 1965 TO 1968, LEVELED OFF BETWEEN 1968 AND 1970, DROPPED SLIGHTLY IN 1971, AND THEN RESUMED ITS RISING TREND. IN ORDER TO MEASURE OTHER FACTORS THAT MIGHT ACCOUNT FOR THE FLUCTUATION IN CRIME RATE, RESEARCHERS STUDIED THE RATE OF THEFT CLEARANCE BY ARREST OR OTHER MEANS WHICH REMOVED THIEVES FROM THE COMMUNITY. AN INCREASE OF 10 PER 1,000 IN THE TREATMENT RATE ACCOMPANIED A DECREASE OF 1 PER 1,000 IN THE THEFT RATE, BUT AN INCREASE OF 10 PER 1,000 IN THE THEFT CLEARANCE RATE ACCOMPANIED A DECREASE OF 6.3 IN THE THEFT RATE. HOWEVER, THE INVESTIGATORS WERE TENTATIVE IN THEIR CONCLUSIONS ABOUT THE RELATIONSHIP BETWEEN THEFT RATE AND NUMBER OF HEROIN USERS IN TREATMENT BECAUSE UNIFORM CRIME REPORTS DO NOT INCLUDE UNREPORTED CRIMES OR CRIMES WHICH DO NOT LEAD TO ARREST. TABULAR DATA AND REFERENCES ARE INCLUDED. (JLF)