The study of defects and disorder in solids remains a central topic in solid state science. Developments in the field continue to be promoted by new experimental and theoretical techniques, while further impetus for the study of disorder in solids is provided by the growing range of applications of solid state materials in which disorder at the atomic level plays a crucial rOle. In this book we attempt to present a survey of fundamental and applied aspects of the field. We consider the basic aspects of defective crystalline and amorphous solids. We discuss recent studies of structural, electronic, transport, thermodynamic and spectroscopic properties of such materials. Experimental and theoretical methodologies are reviewed, and detailed consideration is given to materials such as fast ion conductors and amorphous semiconductors that are of importance in an applied context. Any survey of this large field is necessarily selective. We have chosen to emphasise insulating (especially oxidic) and semi-conducting materials. But many of the approaches and techniques we describe apply generally across the entire field of solid state science. This volume is based on a NATO ASI held at the Residencia Santa Teresa de Jesus, Madrid in September 1991. The Editor is grateful to the NATO Scientific Affairs Division for their sponsorship of this School. Thanks are also due to all who participated in and lectured at the school, but especially to the organising committee of A. V. Chadwick, G. N. Greaves, M. Grigorkiewicz, J. H. Harding and S. Kalbitzer. C. R. A.
