The Symposium was initiated in 1977 by Dr. M. G. CHABERT, Directeur des plans et programmes du C. E. T. I. M. His death, which occurred a few weeks before the Symposium, was deeply felt by all participants, who decided to dedicate this volume to his memory. The purpose, as set out by Dr. CHABERT, was to bring together people speaking the language of research and the language of industry in discussing problems of structural analysis. The Centre Technique des Industries M~caniques (C. E. T. I. M. ) at Sen1is was considered a suitable place for organizing such a meeting. Modern structural analysis, aided by high speed computers, is mainly concerned with non-linear phenomena, such as plasticity, visco-plasticity, damage and fracture mecha- nics. Scientists involved in research in this field also speak two different languages: that of material analysts and that of structural analysts. The Bureau of IUTAM had appointed the following Scientific Committee to implement the ideas proposed by Dr. CHABERT: J. LEMAITRE, Universite Paris VI, ENSET, Cachan, France Chairman J. HULT, Chalmers University of Technology, Gothenburg, Sweden, Co-Chairman G. CHABERT, Centre Technique des Industries M~caniques, Sen1is, France F. A. LECKIE, University of Illinois, Urbana, Illinois, USA G. MAIER, Istituto di Scienza e Technica delle Costruzi- oni, Po1otechnico di Milano, Italy Z. MROZ, Polish Academy of Sciences, Warsaw, Poland G. S.