Three hundred and thirty individuals (80% of the total staff members at a Department of Psychiatry) completed a questionnaire concerning their exposure to patient violence. It was found that over 90% of physicians, nurses and nursing aides had been subjected to patient violence at least once during the entire course of their employment in departments of psychiatry. The following percentages were found for incidents of patients violence occurring during a one year period towards staff while employed in departments of psychiatry: residents (17%), nurses (36%), and nursing aides (52%). The highest frequency was found for nursing staff working in closed wards (75%). Length of employment, and thereby the staff's experience, was not related to exposure to patient violence. Neither sex nor age of the nursing staff were significantly associated with their exposure to patient violence. About 1/3 of the nurses and nursing aides had considered changing their job because of patient violence.