U ntil now, the effects of uncertainty on location patterns have remained largely unexplored. Theories about the way in w hich firm s make decisions to locate have long been restricted by the assum ption that those firm s know all the relevant facts when the decisions are made. This book is an attem pt to generalise location theory to take account of the fa ct that firm s are uncertain when they make their decisions.Among the topics discussed are the location of duopolists, the patterns of tow ns, the production decisions o f firm s, and the im pact of the diffusion of innovations on location. The emphasis is theoretical rather than em pirical. The book contains a collection of largely independent models w hich need now to be more fu lly tested and combined into a mathem atical theory.This is an extrem ely im portant book for geographers and regional scientists. It should become a standard w ork for all advanced university courses in location theory.