Since ovarian cancer remains confined to the peritoneal cavity for the majority of its natural history, it provides us with a unique opportunity to explore the possibility of administering chemotherapeutic agents in direct contact with the tumor. Sound pharmacologic principles have been developed that allow us to predict with accuracy agents that should be useful in this approach. The peritoneal pharmacokinetics of a number of active chemotherapeutic agents have been investigated and several effective agents have been identified. Cisplatin has been extensively investigated and has demonstrated excellent activity when used in this fashion. The recognition of sodium thiosulfate as a renal protective agent, against cisplatin-induced nephrotoxicity, has allowed for significant dose escalation of cisplatin. The favorable pharmacokinetic profile and clinical activity of cisplatin render it an important component of intraperitoneal chemotherapy regimens.