All reported injuries between 1985 and 1987 in a large Queensland psychiatric hospital were studied. There were 650 incidents investigated; travelling injuries and injuries sustained by staff members not involved with patient care were excluded. Forty-eight per cent (n = 323) were assault based injury. Student nurses were most frequently assaulted. It was concluded that training in aggression management should include both counselling and self defence techniques, and that patient and staff rights should be balanced. Student nurses should have experience in wards with a low injury rate, prior to being rostered to the high risk wards.