Recently, genetic analyses in high risk families with several members suffering of breast and/or ovarian carcinoma led to the discovery of two genes, called BRCA1 and BRCA2, clearly responsible for hereditary predisposition of breast carcinoma. Another gene, p53, was also shown to be involved in hereditary predisposition of breast and other tumors in the setting of Li-Fraumeni syndrome. It is very important that women at risk could be seen by a specialized team for genetic counselling and explanation of advances and limits of molecular genetics. Such a team should be multidisciplinary in order to cover genetic, oncological, social, psychological and economical aspects of hereditary cancer predisposition. Prevention interventions and early detection methods are still investigational and definitely need to be performed in the setting of protocols in order to better evaluate their long term efficacy.