Andreu Mas-Colell is currently Emeritus Professor of Economics at the Universitat Pompeu Fabra, Barcelona, Spain. Formerly he was Professor of Economics at Harvard University (1981-96), Professor of Economics and Mathematics at the University of California, Berkeley (1972-80) and Chairman of the Barcelona Graduate School of Economics (2006-2010). He holds Honoris Causa Doctorates from the universities of Alacant, Toulouse, HEC (Paris), Universidad Nacional del Sur (Argentina) and Chicago. He has received the Rey Juan Carlos Prize in Economics (1988), the Pascual Madoz (National Research Prize), (2006) and the Premio Fundación BBVA Fronteras del Conocimiento en Economía, Finanzas y Gestión de Empresas shared with Hugo Sonnenschein- (2009). He has served as main Editor of the Journal of Mathematical Economics (1985-88), and of Econometrica (1988-92). Professor Mas-Colell is a Fellow of the Econometric Society and was its President in 1993. In 1997 he was elected Foreign Associate to the US National Academy of Sciences and Foreign Honorary Member of the American Economic Association. He has been a Sloan Fellow (1978-1980) and Guggenheim Fellow (1985-1986). Also from 1999 to 2005 he was a member of the Executive Committee of the International Economic Association. In the year 2006 he served as President of the European Economic Association. From 2000 to 2003 he was Conseller for Universities and Research of the Government of Catalonia and President of the Advisory Scientific Committee of Telefónica Investigación y Desarrollo (2005-2008). He served as General Secretary of the European Research Council (2009-2010) and Conseller of Economy and Knowledge of the Government of Catalonia (2010-2015). Mas-Colell has written over 120 research papers on subjects ranging from abstract general equilibrium theory and the structure of financial markets to pricing policy for public firms. He is the author of The Theory of General Economic Equilibrium: A Differentiable Approach (Cambridge University Press, 1985) and co-author with M. Whinston and J. Green, of the graduate textbook Microeconomic Theory (Oxford University Press, 1994)."La Fundación Ramón Areces no se hace responsable de las opiniones, comentarios o manifestaciones realizados por las personas que participan en sus actividades."