Science is made offactsjust as a house is made of bricks, but a collection offacts is no more science than a pile of bricks is a house. Henry Poincare The aim of the disciplines of praxis is not theoretical knowledge .... It is to change the forms of action ... .. .. Aristotle Transportation systems engineering is a broad discipline aimed at the functional design of physical and/or organizational projects relating to transportation supply systems. These projects defme the functional characteristics and performances of system elements (services, prices, infrastructures, vehicles, control, etc.) that, taken as a whole, provide transportation opportunities to satisfy the travel demand of persons and goods in a given area. The basic approach of transportation system engineering is to defme the main characteristics of transportation services starting with the analysis and simulation of the demand for such services. Physical elements of the system are designed and/or identified among those available to provide the characteristics and performances required by the transportation services.