The U.S. Congress' response to the escalating increase in Medicare and Medicaid fraud and abuse has been to strengthen existing statutes. This has resulted in a statutory and regulatory scheme that creates civil and criminal sanctions for any person or legal entity that provides health care goods or services in a fraudulent or abusive manner. The Federal Government may also being criminal prosecution under the False Claims Act or other criminal fraud statutes. One section of this article explains features of laws enacted to fight Medicaid and Medicare fraud and abuse. These laws include the Medicaid False Claims Statute, the Medicaid Anti-Kickback Statute, and the amendments that limit physician referrals. Features of the relevant provisions of the Health Insurance Portability and Accountability Act of 1996 (HIPPA) are also reviewed. Another section of the article focuses on enforcement of these statutes. The submission of false statements or claims to Medicare or Medicaid and violations of Medicare or Medicaid anti-kickback provisions are the two major areas of criminal enforcement in the health care sector. This section presents an overview of the Federal agencies responsible for enforcement of these provisions. State-level enforcement, Federal and State cooperation, and compliance programs are also discussed. 476 notes