This authoritative and encyclopaedic reference work provides a thorough account of the public choice approach to economics and politics. The Companion breaks new ground by joining together the most important issues in the field in a single comprehensive volume. It contains state-of-the-art discussions of both old and contemporary problems, including new work by the founding fathers as well as contributions by a new generation of younger scholars.The book reviews the literature of public choice, highlighting the common ground between all rational choice approaches to politics. It demonstrates the important impact of public choice on economics, political science, philosophy and sociology. It will be an indispensable source of reference for many years to the ideas, analytical methods and empirical research in the field.The Companion will serve as the standard reference work for all those engaged in the field of public choice and will be essential reading for politicians and policymakers, scholars in political science, public and social choice, as well as graduate students in economics, political science and public administration.