This book contains eleven chapters describing some of the most recent methodological operations research developments in transportation. It is structured around the main transportation modes, and each chapter is written by a group of well-recognized researchers. Because of the major impact of operations research methods in the field of air transportation over the past forty years, it is befitting to open the book with a chapter on airlineoperations management. While many past publications have focused on airline strategic and tactical planning, Ball, Barnhart, Nemhauser and Odoni have chosen to address the organization and control of recovery operations in the event of disturbances. This line of research is relatively new and of major importance to the airline industry. The second chapter, by Desaulniers and Hickman, surveys the planning of public transit operations. The problems addressed and the methods employed in transit planning, for example those arising in network design, passenger assignment, scheduling, and fleet and crew assignment, are often similar to those of the airlines. The railway optimization chapter, by Caprara, Kroon, Monaci, Peeters and Toth, covers the realm of planning problems encountered in railway planning, with an emphasis on European passenger railways. Again, several of these issues are similar to those observed in other modes, but some problems are specific to the railway industry, such as train platforming, rolling stock circulation, and train unit shunting. The fourth chapter, by Christiansen, Fagerholt, Nygreen and Ronen, contains an extensive survey of maritime transportation problems, methods and applications. Compared with other modes, maritime transportation has received relatively little attention from operations researchers. Yet this field is rapidly expanding with the consolidation of major shipping companies and the development of large container ports.The next three chapters cover a variety of planning problems arising in vehicle fleet management. The chapter by Powell, Bouzaiene-Ayari and Simao addresses truck transportation planning in contexts where information processes are dynamic. The focus is on the development of models that capture the flow of information and decisions. The vehicle routing chapter, by Cordeau, Laporte, Savelsbergh and Vigo, concerns what is arguably the most central problem in distribution management. It surveys several families of vehicle routing problems, including classical models, inventory routing, and stochastic routing. In the transportation on demand chapter, Cordeau, Laporte, Potvin and Savelsbergh consider the planning of pickup and delivery operations made at the request of users, such as those encountered in courier services, dial-a-ride operations, dial-a-flight systems, and ambulance fleet deployment.