Harmonic Mappings, Twistors And Sigma Models

Harmonic mappings have played in recent years and will likely to play in the future an important role in Differential Geometry and Theoretical Physics, where they are known as s-models. These Proceedings develop both aspects of the theory, with a special attention to the constructive methods, in particular the so-called twistorial approach. It includes expository articles on the twistorial methods, the various appearence of -models in Physics, the powerful analytic theory of regularity of SCHOEN-UHLENBECK.