The prevalence of maladaptive behavior was investigated for retarded individuals residing in institutions, community facilities or their own home. The relationship beweeen behavior problems and sex, age, level of retardation and race was examined. A higher prevalence of behavior problems in the institutions as compared to community placements was found. The profoundly retarded individuals, unless handicapped by not be being able to move around, exhibited more injurious behavior than moderately and mildly retarded persons.