Dramatic progress has been made in the fundamentals of fracture, with special emphasis on the ductile/brittle transition across a broad spectrum of material classes. Unfortunately, however, since these studies are carried out in diverse research communities, communication among the different groups is limited. This book brings these diverse groups together. Contributions generally follow the topical outline upon which the symposium was organized. Part I deals with brittle/ductile behavior of steels and structural metallic alloys. The development of analytical models based on micromechanical models, such as dislocation mechanics and cohesive/contact zone models, is the focus of Part II. Nonmetals, including silicon, are reviewed in Parts III and IV. Fractals, chaos, and scaling theories, with emphasis on fracture in heterogeneous solids, is the basis of Part V. Crystal plasticity and mesoscale dislocation modelling follow in Part VI, with the technologically significant area of interfacial fracture featured in Part VII.