This book examines the molecular dynamics that occur within zeolites. Our understanding of how these marvelous catalysts work has been greatly enhanced by the advent ot new tools such as NMR, scanning-transmission-electron microscopy, and sophisticated computer modelling. By combining recent findings and newly developed models with classical developments in the theory of diffusion, this book provides a complete picture of the physical chemistry of hydrocarbon transformation in zeolites. It should be an excellent guide to those involved in catalyst design.