The present volume has its source in the CAP-CRM summer school on Particles and Fields that was held in Banff in the summer of 1994. Over the years, the Division of Theoretical Physics of the Canadian Associa- tion of Physicists (CAP) has regularly sponsored such schools on various theoretical and experimental topics. In 1994, the Centre de Recherches Mathematiques (CRM) lent its support to the event. This institute, located in Montreal, is one of Canada's national research centers in the mathe- matical sciences. Its mandate includes the organization of scientific events across Canada and since 1994 the CRM has been holding a yearly summer school in Banff as part of its thematic program. The summer school, whose lectures are collected here, has thus become a tradition. The focus of the school was integrable theories, matrix models, statistical systems, field theory and its applications to condensed matter physics, as well as certain aspects of algebra, geometry, and topology. This covers some of the most significant advances in modern theoretical physics. The present volume updates and expands these lectures and reflects the high pedagogical level of the school. The first chapter by E. Corrigan describes some of the remarkable fea- tures of the integrable Toda field theories which are associated with affine Dynkin diagrams. The second chapter by J. Feldman, H. Knorrer, D. Leh- mann, and E.