The present study examined the prevalence and comorbidity of mental disorders according to DSM-III-R among male and female suicide attempters. A systematic sample of 114 patients from consecutive cases of attempted suicide referred to a general hospital in Helsinki between 1 January and 31 July 1990 was interviewed. In 98% of the cases at least one Axis I diagnosis was made. Depressive syndromes were more common among females (85%) than males (64%), and alcohol dependence was more common among males (64%) than females (21%). A high proportion of suicide attempters (82%) suffered from comorbid mental disorders. Comorbidity appears to play an important role in parasuicide.