To mark its hundredth Round Table on transport economics, the ECMT decided to publish a special issue. Fifty European experts were asked to submit papers examining not only the major issues addressed by transport economics in the past, but also those that are likely to emerge in the future. What are the main difficulties facing transport economics? What have been the main advances and how can they help us to solve problems? What remains to be done? The same fifty experts were then invited to take part in an open debate on the issues which they had raised in their papers, ranging from methodological tools to strategies for European transport policies and from the situation of countries in transition to the environment, intermodal transport, new technologies, infrastructure and many other topics. These papers are presented in this volume which also includes a full summary of the discussions at the Round Table.