The study of transport is the study of movements, of displacements of individuals and things in both space and time. The objective of this book is to provide the basic concepts and tools for the economic analysis of transport systems, with emphasis on the behaviour of users and operators. Distinctive features will be introduced and treated as the natural consequence of processes that deal with displacements in space-time. Emphasis will be given to the operation of transportation systems, i.e. to the actual form of combining vehicles, terminals and rights-of-way in order to produce certain level of flows of different things in different directions. Thus, ours will be a short run oriented view, dealing with the adequate usage of resources for given levels of investment. This book focuses on the behavior of users and operators outside of traditional economic behavior theory. It includes time and space as a distinctive feature of transport economics.