The identification of genes that place individuals at high risk of breast, ovarian, and colorectal cancer has greatly advanced our understanding of cancer predisposition over the past decade. This knowledge has received much attention from the media, and referrals to geneticists and surgeons, and requests for genetic testing, have risen. We review the published evidence for the management of people at increased risk of hereditary cancers, to draw attention to areas of uncertainty and to discuss implications for primary care. We focus on common inherited cancers, since they will have the greatest effect on clinical practice over the next decade. Cancer genetics offers a model of how information on the genetics of other common diseases could affect primary care in the future. Strategies to support the integration of genetic medicine in primary care are needed to enable primary-care practitioners to identify individuals at raised genetic risk and to reassure patients for whom genetic testing and increased surveillance offer little benefit.