The collection of articles in this volume represents the proceedings of the inau­ gural Conference of the Institute of Theoretical Matter Physics at the University of Florence, Italy, June 7-13, 1990. The aim of this Institute (sponsored by the Con­ sorzio Interuniversitario di Fisica della Materia, INFM) is to foster interdisciplinary approaches to theoretical problems in Solid State, Electronics and Optics. Corre­ spondingly, the Conference surveyed a broad scope of modern analytic techniques in nonlinear science and their application to novel liquids, solids and optical environ­ ments. The Conference was held at Centro Studi CISL, a magnificent Villa up to Florence. The major topics addressed through survey and specialized lectures, discussions and posters were: Complexity and Coherence in spin glasses, associative distribu­ tive memory, low dimensional electronic materials, magnets, Josephson junction ar­ rays, optics, semiconductors, convection cells, material science, high-temperature superconductivity, Physics of Quantum Devices such as nonlinear feedback oscilla­ tors, macroscopic quantum tunneling, hetero structures, quantum ballistic devices, tunneling in atomic devices, Field Theory and Statistical Mechanics, especially for soliton-bearing and quantum chaotic systems. Many exciting ideas and results were presented and debated in lively fashion. Perhaps two major themes were evident throughout the workshop.