A model is presented that describes the life of large transportation projects. The model has six stages, each one devoted to a different part in the life of the project: prehistory of the project, project development, procurement, implementation, operations and maintenance, and long-range impacts and economic restructuring. This six-stage model should help planners and project promoters go through the task of developing and implementing large transportation projects. The model describes the different issues in each stage and embedded in the discussion are ways for addressing them. The political, institutional, as well as technical aspects are addressed, and they are linked to show how they affect the evolution of the project. The analysis presented in the six-stage model can be interpreted as a call for planners and project promoters to acknowledge that large transportation projects are very complex and that planning and implementing them requires planners and promoters to behave in a strategic way that includes intertwining technical and political issues.