Gastrointestinal and ovarian malignancies frequently recur with metastatic disease limited to the abdominal cavity. Due to full thickness penetration of tumor through bowel wall, spillage of tumor from lymphatic channels by surgical trauma or perforation of the tumor through the ovarian capsule, tumor cells are disseminated throughout the peritoneal surfaces either prior to or at the time of surgical removal of the primary tumor. In the past, diagnosis of recurrent cancer was difficult because no sensitive diagnostic test was available by which to image a small tumor volume present on peritoneal surfaces. Computerized tomography with intraperitoneal infusion of contrast can demonstrate tumor nodules not otherwise detectable. Intraperitoneal installation of I-131 labeled monoclonal antibody has allowed visualization of mucinous tumor on peritoneal surfaces not seen by any other radiologic test. Intraperitoneal chemotherapy has been shown to provide palliation in patients with small volume disease confined to peritoneal surfaces. Because of limited penetration of chemotherapy into large tumor nodules this treatment strategy has not been effective for bulky intraabdominal recurrent cancer. Cytoreductive surgery utilizing high voltage electrocautery and CO2 laser evaporation of tumor can make patients relatively disease free. These surgical technologies combined with postoperative intraperitoneal chemotherapy have been shown to be of benefit for selected patients with recurrent intraabdominal cancer. The wider application of these intraperitoneal chemotherapy treatments for patients in an adjuvant setting may be of value in preventing the occurrence of peritoneal carcinosis and in improving survival.