Massimo Morelli is Professor of Political Science and Professor of Economics at Columbia University since 2007. He has received his PhD in Economics at Harvard University in 1996, has been a research fellow at the Center for Operation Research and Econometrics in 1997, has taught at Iowa State University, University of Minnesota and Ohio State University, and has been a Fellow of the Institute for Advanced Study in Princeton. In Economic theory he has made contributions to coalition and network formation, market games, bargaining theory and the theory of contracts. His main political economy contributions have been on party formation, electoral systems, international organizations, legislative bargaining theory and experiments, politicians' incentives in institutional reforms and constitutional design. His most recent research projects on the rational choice approach to conflict include the role of natural resources and geography, dispute resolution mechanisms, mediation and strategic militarization. In terms of institutional design, he is working on transparency, quorum rules, separation of powers and optimal organization design in the presence of career concerns.