The vast majority of Medicare claims are processed without undergoing claims review, creating vulnerability for the Medicare Trust Funds. Through various legislative actions, CMS has contracted with claims review entities to perform post-payment and pre-payment claims review, and audits of Medicare FFS claims have increased exponentially over the past decade. The book presents an overview of the various CMS contractors performing claims review (including post-payment and pre-payment auditing activities). Additionally, the uniform Medicare Part A and Part B appeals process is covered in great detail. Appeal strategies are set forth along with legal challenges applicable to Part A and Part B unfavorable claims determinations, with which attorneys should familiarize themselves when representing a health care entities subject to audit. A helpful list of resources and references is included to further aid the reader.