[en] Investigated supervisory attentional system (SAS) functions in schizophrenic patients. 15 schizophrenic outpatients (mean age 29.93 yrs) and 15 normal controls matched for age, gender, and educational level were compared. Three tasks (Tower of London, Hayling, and Brixton tests) were used to examine 3 executive processes (planning, inhibition, and rule detection). Schizophrenic patients performed significantly worse than normal controls on all 3 tasks. In addition, patients' performances on selected measures of the three tests were correlated, even when age and medication were partialled out. It is concluded that patients are impaired on all SAS functions. The possible role of a general impairment (processing speed or cognitive resources) is discussed