Background. The aim of the study was to compare the hospital management and direct costs of self-poisoning in six United Kingdom hospitals and to investigate whether hospital management influences outcome. Method. This was a prospective descriptive study carried out at three teaching hospitals and three district general hospitals in North West England on adults (aged 16 or over) presenting to the study centres with deliberate self-poisoning over a 5-month period. Data were based on demographic and clinical characteristics, management of the current episode, direct costs and repetition of self-poisoning within 12 weeks of index episode. Results. There were 1778 episodes of self-poisoning during the study period. There were marked differences in management between centres. There was a fivefold difference in the rate of admission to a medical bed (16.5%-81.3%), and a twofold difference in the rate of psychosocial assessment (28.5%-57.7%). These differences remained after adjustment for demographic and clinical factors. Hospital costs per episode varied from £228 to £422 and repetition rate ranged from 10% to 16%. Psychosocial assessment was associated with a twofold reduction in the risk of repetition. Conclusions. The marked variability of services for self-poisoning continue. It seems likely that this is having a detrimental effect on patient outcomes. Large scale intervention studies are required to inform both clinical practice and service provision.