Familial ovarian cancer occurs in approximately 5% of all ovarian cancers. Since the relation between ovarian cancer and genetic heritage has drawn much attention lately, general gynaecologists will more and more be faced with the question how to survey patients from a family with the familial ovarian cancer syndrome. We describe a patient from a family with three daughters, of which two older sisters were known to have ovarian cancer. Although our patient was closely observed, a third-stage ovarian cancer developed. With this case in mind and after a review of the literature, we will in future closely survey patients from familial ovarian cancer families from their twentieth birthday on, and recommend prophylactic bilateral oophorectomy after child-bearing age. However, we are aware of the fact that it is impossible to diagnose ovarian cancer in a premalignant phase as yet, and the benefit of a close survey might be an earlier diagnosis and not prevention. Also, prophylactic oophorectomy does not prevent the occurrence of intra-abdominal malignancies histopathologically indistinguishable from ovarian cancer. Patients should be aware of these restrictions. If, in the future, the precise chromosomal defect in ovarian cancer families is localized, prevention of ovarian cancer, but not of intra-abdominal malignancies of the same histopathology, might be within reach.