Of the female patients (N = 26) on a state hospital unit who remained chronically institutionalized and actively psychotic despite psychopharmacologic and psychosocial treatment, 12 (46%) reported histories of childhood incest. These 12 patients were more likely than the others to engage socially with ward staff. A higher proportion had sexual delusions, affective symptoms, substance abuse, suspected organicity, and major mental problems, and they spent more time in seclusion than other patients. The authors acknowledge the difficulty of assessing the accuracy of reports of incest. They discuss the implications of a possible relationship between incest and severe, intractable psychotic disorder.