The study will consist of enrolling approximately 8360 patients aged 35-65 years who attend primary care practices that are part of research networks affiliated with the three research centers. The practices will be randomized into two groups. Patients in practices randomized to Group 1 will complete a pre-test and the family history tool, and will receive personalized prevention messages based on their level of familial risk and current risk behaviors. After six months, Group 1 patients will complete a post-test. Patients in Group 2 will complete the pre-test and receive standard prevention messages (appropriate for sex) about maintaining good health and preventing disease. After 6 months Group 2 patients will complete the post-test and the family history tool. The pre- and post-test will include assessment of risk factors, use of medical services (especially preventive services), interest in modifying health behaviors, risk perceptions, etc. The analysis will compare changes in health behaviors between patients in Groups 1 and 2 and will also examine differences by familial risk strata (average, moderate, high).