Ovarian cancer is the leading cause of gynecologic cancer deaths in the U.S. The concept of intraperitoneal drug delivery for therapy of intraperitoneal cancers, such as ovarian cancer, arose in the 1960s. The field of intraperitoneal cisplatin therapy for ovarian cancer was initiated in the late 1970s and early 1980s. The markedly improved survival data resulting from a third phase III trial of intraperitoneal cisplatin for ovarian cancer in early 2006 led to an NCI Clinical Announcement and a Gynecologic Oncology Group-sponsored workshop on Intraperitoneal Therapy in January, 2006, in San Diego, California. The proceedings of this workshop summarize both research trial results and practical implementation issues associated with intraperitoneal therapy discussed at this workshop.