This text records the Proceedings of the IUTAM Symposium held in Cambridge in 1995. It contains 35 articles by leading authorities and addresses the modelling of fracture from a variety of perspectives, ranging over mechanics, material science, physics, geophysics, and nonlinear dynamics. The most important single practical question that is addressed is that of scale. This is considered in relation to nonlinear material behaviour, micromechanics and statistical variations, and the interaction of these aspects. Certain parts of the subject have recently experienced significant advance, from one or other of the standpoints of physics, materials science or mechanics. This book is intended to contribute towards the wider dissemination of these advances and the development of a unified perspective. It will be useful to those active in research in fracture who wish to gain an overview of the subject, taking advantage of insights gained from the whole range of this expertise.