Ronald Wintrobe is Professor of Economics at the University of Western Ontario. He is the author of numerous articles in economics and political science journals, and is the author, editor or co-editor of 9 books, including The Political Economy of Dictatorship (Cambridge University Press 1998) and, most recently, Political Extremism and Rationality (Cambridge University Press 2001, co-edited with Albert Breton, Gianluigi Galeotti and Pierre Salmon). Currently, he is working on a book on the economics of group behaviour.