Sexual contacts between nurses and patients in psychiatric hospitals have not been investigated systematically. The aim of the present study was to determine the frequency of nurse-patient sexual relationships and their prominent characteristics on the one hand and the nurses' attitudes towards these contacts on the other. A questionnaire was mailed to 714 nurses employed at two psychiatric hospitals. Although 94% of the 279 respondents considered sexual contact (defined as "physical contact between a patient and a nurse, in which sexual arousal occurred in the nurse") to be inappropriate, 17% of the male and 11% of the female responding nurses reported having had such contacts with patients.