The fraud and abuse laws that govern conduct related to the federal health-care programs, such as Medicare and Medicaid, impose broad and complex limitations on billing practices and financial relationships among providers. Given the potential consequences of engaging in fraudulent behavior, it is crucial that physicians appreciate the types of activities that may run afoul of these laws. This article summarizes the major aspects of the fraud laws that are most likely to have a daily impact on physician practice: the Civil False Claims Act, the Medicare and Medicaid Anti-Kickback Statute, and the so-called Stark Law prohibition on physician self-referrals.