The records of 2,115 patients with ovarian cancer who were treated at the M.D. Anderson Hospital and Tumor Institute in Houston, Texas, during the 30 year period from 1944 to 1973 were reviewed. Ninety percent of the patients had an epithelial cancer of the ovary. The important prognostic factors include stage and grade of tumor and the presence or absence of ascites. Probably the most important prognostic factor, however, was the size of the largest tumor mass that remained after initial surgery. The patient's age and socioeconomic level were also influencing factors in the survival rate in this series of patients. Most of the patients had advanced disease when first examined and received some type of adjunctive postoperative treatment. The survival of patients who received postoperative irradiation, when compared by stage and size of the largest residual tumor mass, was improved over those who received chemotherapy.