The value of secondary cytoreductive surgery at the time of second-look laparotomy in patients with epithelial ovarian carcinoma is not established. Sixty-seven patients with residual carcinoma found at the time of second-look laparotomy performed at Memorial Sloan-Kettering Cancer Center between December 1, 1978, and May 30, 1986, were evaluated for survival relative to the success of secondary cytoreductive surgery. At second-look laparotomy, 17 patients had microscopic disease, 28 patients had disease less than 2 cm and 22 patients had disease greater than 2 cm. After secondary cytoreductive surgery 33 patients had microscopic disease, 26 patients had disease less than 2 cm, and 7 patients had disease greater than 2 cm (1 unknown). Five-year survival by Kaplan-Meier calculation was 62% for patients found to have microscopic disease at second-look laparotomy and 51% for patients whose disease was rendered microscopic by secondary cytoreductive surgery (P = 0.55). Patients left with gross disease (either less than or greater than 2 cm) had 5-year survivals of less than 10% (P = 0.013 compared with microscopic residual). Secondary cytoreductive surgery at the time of second-look laparotomy in patients with epithelial ovarian carcinoma may result in improved survival of patients who are reduced to microscopic residual disease.