A rigorous mathematical treatment of the properties of composite materials has been made possible by recent mathematical results in the fields of partial differential equations and the calculus of variations. The progress in the mathematical models for composite media has led to a deeper understanding of the overall behaviour of composite structures and to significant applications in physics and engineering, including a new approach to optimal design problems.Many new, relevant results are presented in this volume, which contains 16 invited papers from the Second Workshop on Composite Media and Homogenization Theory held at the International Centre for Theoretical Physics in Trieste, Italy, from September 20 to October 1, 1993. Topics include homogenization of problems singularly depending on small or large parameters, homogenization of nonlinear problems, optimal bounds for effective moduli, asymptotic analysis of problems in perforated domains, laminate structures in phase transitions, optimal design and relaxation. Mathematicians and engineers interested in mathematical models of composite materials will find this book to be an important reference.