This book contains proceedings of an international symposium on Atomistic th Simulation of Materials: Beyond Pair Potentials which was held in Chicago from the 25 th to 30 of September 1988, in conjunction with the ASM World Materials Congress. This symposium was financially supported by the Energy Conversion and Utilization Technology Program of the U. S Department of Energy and by the Air Force Office of Scientific Research. A total of fifty four talks were presented of which twenty one were invited. Atomistic simulations are now common in materials research. Such simulations are currently used to determine the structural and thermodynamic properties of crystalline solids, glasses and liquids. They are of particular importance in studies of crystal defects, interfaces and surfaces since their structures and behavior playa dominant role in most materials properties. The utility of atomistic simulations lies in their ability to provide information on those length scales where continuum theory breaks down and instead complex many body problems have to be solved to understand atomic level structures and processes.