In view of the rarity of germ cell tumors of the ovary, it is not surprising that little information exists about the indications for and significance of findings at second-look laparotomy in patients with these tumors. For this reason, we have reviewed 16 patients who received primary chemotherapy for malignant germ cell tumors of the ovary at Memorial Sloan-Kettering Cancer Center (MSKCC) between 1976 and 1983. Eleven of them underwent a second-look laparotomy after completion of their therapy. Primary therapy consisted of surgery, usually unilateral oophorectomy, and cis-platinum-based VAB chemotherapy. The histologic diagnoses were six immature teratomas, five endodermal sinus tumors, four mixed germ cell tumors, and one nongestational choriocarcinoma. Stage distribution was as follows: Stage IA, eight patients; Stage IC, one patient; Stage IIA, one patient; Stage III, four patients, and unstaged, two patients. The ages ranged from 15 to 56 years, with the mean of 29 years. All of the 11 patients undergoing second-look laparotomy were found to be free of disease. They are alive and have been continuously free of disease from 9 to 77 months (mean 39 months). This paper discusses primary chemotherapy and the role of the second-look laparotomy and suggests its value in modifying treatment, predicting cure, and safely stopping therapy in patients with germ cell malignancies of the ovary.