We have studied the effectiveness of a neuroleptic, sultopride, in difficult patients with mental impairment and severe disorders of behavior and character. Twenty patients were entered into the study. Specific items were evaluated one week, two months and four months after initiation of treatment. Disorders of character abated quickly and significantly. Tolerance was satisfactory. Overall results were satisfactory in 75% of patients, with 55% good and 20% very good responses. Failures were recorded in patients with associated disorders of personality and affect.