Malignant peritoneal mesothelioma remains a therapeutic problem. A review of the use of intraperitoneal 32P and a review of the status of therapy for this disease are presented. Six patients treated with 32P and combinations of external radiation therapy, surgery, and chemotherapy are reviewed with survival times from 5 months to 18 years. Overall survival in this disease is poor, about 44.2 months. This series suggests that with combined therapy with intraperitoneal 32P and chemotherapy, longer survivals can be achieved.