This book is the third volume of lecture notes from summer schools held in the small village of Peyresq (France). These lectures cover nonlinear physics in a broad sense. They were given over the period 2004 to 2008. The summer schools were organized by the Institut Non Lineaire de Nice (Nice, France), the Laboratoire de Physique Statistique (ENS Paris, France) and the Institut de Recherche de Physique Hors Equilibre (Marseilles, France). The goal of the book is to provide a high-quality overview on the state of the art in nonlinear sciences, and to promote the transfer of knowledge between the various domains in physics dealing with nonlinear phenomena.