THE ECOLOGICAL APPROACH TO THE STUDY OF CRIME ATTEMPTS TO EXPLAIN CRIMINAL PHENOMENA AT THE MACRO LEVEL THROUGH THE DISCOVERY OF SPATIAL PATTERNS OF CRIME AND STUDY OF THE SOCIAL AND ECONOMIC CONDITIONS OF THE AREAS STUDIED. DATA FOR THE STUDY WERE OBTAINED FROM THE 1971 CENSUS PUBLICATIONS OF STATISTIC CANADA AND THE FILES OF THE OTTAWA POLICE. DEMOGRAPHIC AND SOCIOSTRUCTURAL VARIABLES WERE CONSIDERED. MALE AND FEMALE UNEMPLOYMENT RATES, THE PROPORTION OF TENANT-OCCUPIED BUILDINGS, AND THE NUMBER OF PERSONS PER FAMILY WERE FOUND TO BE SIGNIFICANT PREDICTORS OF CRIME. FINDINGS ALSO SHOWED THAT ATTEMPTS TO PREDICT CRIME OTHER THAN SEX OFFENSES WITH THE ECOLOGICAL VARIABLES ARE USELESS. THEY ALSO INDICATED THAT THE INFORMATION OBTAINED FROM ONE TECHNIQUE OF ANALYSIS WAS NO DIFFERENT FROM THAT OBTAINED BY THE OTHER. THE FINDINGS, HOWEVER, CANNOT BE CONSIDERED DEFINITIVE BECAUSE THE NUMBER OF VARIABLES CONSIDERED WAS RELATIVELY SMALL. TABULAR DATA AND REFERENCES ACCOMPANY THE REPORT. (MJW)