In this study 368 patients were interviewed after they had attended the Bristol Royal Infirmary Accident and Emergency Department following a non-fatal act of deliberate self-harm. There were twice as many women (247) as men (121), and two thirds of the patients were in the 15-35 age group. Ninety-five per cent had taken a drug overdose, most commonly one or more of the tranquillizers, antidepressants, hypnotics or analgesics. Seventy-eight per cent had taken drugs prescribed by a doctor. Half the patients mentioned interpersonal conflict as a major precipitating factor in the episode. A psychiatric diagnosis was completed for all admitted patients, of whom 52 per cent were considered to be suffering from neurotic depression, 29 per cent from personality disorder, 12 per cent from functional psychosis and 10 per cent from alcohol addiction. Almost half had deliberately harmed themselves on a previous occasion. The series showed a greater than average incidence of unemployment, overcrowded living conditions, divorce and antisocial behaviour. The implications of these findings for the clinical management and prevention of non-fatal deliberate self-harm are discussed.