This volume contains the Proceedings of the Workshop on Composite Media and Homogenization Theory held in Trieste, Italy, from January 15 to 26, 1990. The workshop was organized by the International Centre for Theo retical Physics (ICTP); part of the activity was co-sponsored by the Interna tional School for Advanced Studies (SISSA). The workshop covered a broad range of topics in the mathematical the ory of composite materials and homogenization. Among the specific areas of focus were homogenization of periodic and nonperiodic structures, porous me dia, asymptotic analysis for linear and...