Marc Fleurbaey is Professor at the Centre de Recherche Sens, Ethique, Societe (CERSES) at the University of Paris-5 and Research Director at the CNRS, France. He is also serving as a Lachmann Fellow at the London School of Economics in 2006-08. Professor Fleurbaey coedited the Cambridge University Press journal Economics and Philosophy from 2000 to 2004. Maurice Salles is Professor of Economics at the University of Caen, France, where he has taught since 1984. Coordinating editor of the journal Social Choice and Welfare since 1984, he coedited the volume Social Choice, Welfare, and Ethics (Cambridge University Press, 1995) and has served as an Honorary Research Associate at the London School of Economics since 2002. John A. Weymark is Professor of Economics at Vanderbilt University, Nashville, Tennessee. He served as Professor of Economics at the University of British Columbia from 1986 to 1999. Professor Weymark is President-Elect of the Society for Social Choice and Welfare through 2007 and also serves as a Managing Editor of the journal Social Choice and Welfare.