A total of 810 adults were examined by psychiatrists in the second stage of the Eastern Baltimore Mental Health Survey. A semistructured examination, the Standard Psychiatric Examination, was used. The relationships between obsessions and compulsions and personal characteristics, childhood behaviors, family history, and other psychopathology were evaluated. The estimated prevalence of obsessions and compulsions in this population was 1.5%. Cases were significantly more likely to report having had childhood fears, learning disabilities and a family history of alcoholism and suicidal behavior. There were significant positive relationships between scores on compulsive, borderline and histrionic personality disorder scales and the probability of obsessions and compulsions. These exploratory analyses in an epidemiologic sample may identify factors of etiologic importance in this condition.