Objective Behavioral interventions designed to improve functioning of older patients with schizophrenia and other chronic psychotic disorders have the potential to significantly increase patients' independence and quality of life. This study evaluated a psychosocial intervention designed to improve everyday living skills of middle-aged and older outpatients with chronic psychotic disorders. Methods A total of 240 patients with a DSM-IV-based chart diagnosis of schizophrenia or schizoaffective disorder participated in a 24-week, randomized controlled trial comparing a behavioral group intervention called “Functional Adaptations and Skills Training” (FAST; n =124) to a time-equivalent attention-control (AC; n =116) group focused on improving functional skills. Results Compared to participants randomized to AC, those in the FAST intervention demonstrated significant improvement in everyday living skills (p =.046) and social skills (p =.003), but not medication management skills (p =.268). Conclusions Results suggest that middle-aged and older patients with psychotic disorders may benefit from participation in interventions designed specifically to improve functional skills.