Intraoperative chemotherapy with heat has been identified as a treatment option for patients with cancer spread to peritoneal surfaces. This treatment modality is viewed as a supplement to several other treatments for this group of patients including cytoreductive surgery, systemic chemotherapy, early postoperative intraperitoneal chemotherapy, and long-term bidirectional chemotherapy. The pharmacologic basis for using heat to supplement chemotherapy effects are related to the increased penetration of chemotherapy into tumor with hyperthermia, the delayed clearance of chemotherapy from the peritoneal cavity after direct instillation, and an increased cytotoxicity that has been documented with selected chemotherapy agents. Data to support the use of perioperative hyperthermic intraperitoneal chemotherapy with mucinous appendiceal carcinomatosis comes from a large number of single institution phase II studies. Also, peritoneal and pleural mesothelioma are benefited. In colon cancer carcinomatosis, large phase II multi-institutional trials and a single phase III trial documented an increased median survival of these patients from approximately 1 year to over 2 years. Prophylaxis against peritoneal carcinomatosis in gastric cancer has been demonstrated in phase III trials. In ovarian cancer the rationale for this treatment remains large but its current application is limited. Much work needs to be done to identify a proper clinical perspective on hyperthermia used with chemotherapy in patients with peritoneal surface malignancy.