OBJECTIVE The authors determined the rates and patterns of violence toward persons by psychiatric patients before admission to the inpatient service of the Payne Whitney Clinic and determined which factors were associated with a greater risk of violence. METHODS During hospitalization, 763 patients were interviewed by a research assistant using a structured interview instrument. The interviewer inquired about demographic and socioeconomic information and about history of violence and alcohol and drug use. RESULTS Having physically attacked another person in the month before admission was equally likely among male (13.6%) and female (14.7%) patients. The patterns of violence were similar for men and women in terms of target, severity of injuries, use of a weapon, and place of occurrence. Univariate analyses showed that only youth was associated with violence for male patients, while youth, low socioeconomic status, substance abuse, and axis II pathology were associated with a greater risk of violence for female patients. Logistic regression analyses showed that recent cocaine use was significantly associated with violence by female patients when age, socioeconomic status, and axis II pathology were controlled for. For male patients, recent heroin use was related to a greater risk of violence. CONCLUSIONS The frequency of violence by female patients was 150% higher than it was in a study at the Payne Whitney Clinic a decade ago. The frequency of violence by male patients was 50% higher than it was a decade ago. In the current study, substance abuse was associated with greater risk of violence by patients.