Time : Poincaré Seminar 2010 This eleventh volume in the Poincaré Seminar Series presents an interdisciplinary perspective on the concept of Time which poses some of the most challenging questions in science. Five articles written by the Fields medalist C. Villani the two outstanding theoretical physicists T. Damour and C. Jarzynski the leading experimentalist C. Salomon and the famous philosopher of science H. Price describe recent developments related to the mathematical physical experimental and philosophical facets of this fascinating concept. These articles are also highly pedagogical as befits their origin