This book is the first comprehensive analysis of the politics behind the use of mandates requiring state and local governments to implement federal policy. Over the last twenty-five years, during both liberal and conservative eras, federal mandates have emerged as a resilient tool for advancing the interests of both political parties. Revealing the politics that led to the policies, Paul L. Posner explores the origins of these congressional mandates, what interests and needs they satisfy, whether mandate reform initiatives can be expected to alter their use, and their implications for federalism. This book reveals how mandates have changed the way policy is formed in the United States and the fundamental relationship between the federal government and the state and local governments.