The characteristics of 9,365 patients admitted to public hospitals in a one-year period were analyzed in relation to the presence of assaultive or suicidal problems prior to admission. There were definite differences in the occurrence of assaultive or suicidal problems in relation to sex, age, primary diagnosis, education, race, marital status, prior private care, and source of referral to the hospital. There were no significant differences in regard to the history of previous psychiatric admissions, veteran status, or history of seizures. These findings demonstrate the usefulness of a large, routinely collected data base in the study of specific psychiatric problems and offer directions for intervention and future research in the field of life-threatening behavior.