I review the history and politics of Medicare disease prevention policy and identify factors associated with the success or failure of legislative initiatives to add preventive services benefits to Medicare. Between 1965 and 1990, 453 bills for Medicare preventive services were introduced in the U.S. Congress, but not until 1980, after 350 bills had failed, was the first preventive service added to the Medicare program. Medicare currently pays for only four of the 44 preventive services recommended for the elderly by the U.S. Preventive Services Task Force (pneumococcal and hepatitis B vaccinations, Pap smears, and mammography). In addition, Congress has funded demonstration programs for the influenza vaccine and comprehensive preventive services. The preventive services added to Medicare reflect the bias of the biomedical model toward screening and immunizations. Counseling services have received the least legislative attention. Factors associated with successful enactment include ...