Ovarian cancer is the leading cause of death from gynecologic cancer in the United States. Although the etiology of ovarian cancer is unknown, a number of factors including advancing age, nulliparity and environmental factors have traditionally been related to risk. More recently, genetic predisposition has been recognized as a strong risk factor for ovarian cancer. Three distinct hereditary syndromes have been identified: (1) breast-ovarian cancer syndrome, (2) hereditary nonpolyposis colon cancer, and (3) site-specific ovarian cancer. The mode of inheritance in these families is autosomal dominant with transmission occurring through either the maternal or paternal line. The breast-ovarian and site-specific ovarian cancer family syndrome have been linked to a gene on chromosome 17q that is called BRCA1. However, no simple genetic test can identify women at high risk of the disease. For this reason, genetic counseling, education and surveillance with currently available screening techniques should be made available to women at high risk of ovarian cancer by virtue of their family history. In selected individuals, prophylactic oophorectomy may be warranted.