Nowadays, the major tasks of the increasing number of family cancer clinics are to provide general information about cancer, to perform risk assessment, to offer (presymptomatic) DNA-testing, to advise on lifestyle, to take steps for early detection and prevention of cancer, for psychological support and to carry out research programmes by a multidisciplinary approach. In approximately 25-30% of the families with a hereditary pattern of breast cancer a germline mutation can be demonstrated, most commonly in the BRCA1 and BRCA2 genes. Mutations in these genes are associated with high life-time risks of breast and ovarian cancer. The introduction of MRI increased the sensitivity for early detection of breast cancer in comparison with mammography. Thusfar, prophylactic bilateral total mastectomy is the most effective and safest way of prevention but prophylactic oophorectomy and chemoprevention are reasonable alternatives. In particular young women with children make use of DNA-testing and surgical prevention. By a shared decision-making process, the patient and her medical doctor have to make the right choice of management policy based on her individual circumstances.