During the 11-year interval from January 1971 to January 1982, 50 of 246 patients with advanced (Stage III and IV) epithelial ovarian carcinoma at second-look laparotomy had biopsy or cytologic evidence of persistent microscopic carcinoma. The stage and grade profile include 46 Stage III and 4 Stage IV patients: 4 borderline, 9 grade 1, 20 grade 2 and 17 grade 3 patients. Following second-look laparotomy, 4 patients received no further therapy, 45 received chemotherapy, and 1 received external radiation. No patient was lost to follow-up, and the median interval off therapy was 24 months. Progressive or recurrent disease has manifest in 12 (24%). No recurrences have developed either in patients younger than age 40 or in patients with grade 1 tumors. Two patients died of leukemia, 1 died of heart disease, and 35 (70%) are alive with no evidence of disease. In patients developing recurrence, the median progression-free interval was 17.5 months, with a range of 6 to 46 months. The median interval of survival following disease progression was 7 months. There was no evidence of progression at 2 years and 5 years in 81% and 70% of patients, respectively. The uncorrected 2- and 5-year survival rates were 96% and 71%, respectively. The 5-year survival rates for grades 1, 2, and 3 were 100%, 79%, and 36%, respectively. Other variables analyzed include number of positive foci, residual tumor volume at initial surgery, cytologic findings at second-look laparotomy, type of chemotherapy, and number of courses of chemotherapy before second-look laparotomy. In summary, patients with only microscopic evidence of disease at second-look surgery have a good probability for extended survival.