For the past 5 years the Regional Strategies for the Sustainable Intermodal Transportation Enterprise (ReS/SITE) project has worked on the development of new regional transportation planning frameworks that recognize the realities of modern-day regional economic development. The project began with the identification of a number of weaknesses in conventional regional transportation planning and set about the development of an expanded framework that would remedy these shortcomings (including intermodalism, technology scanning, freight, private-sector involvement, economic integration, national information infrastructure-telecommunications-transportation relationships, master plan perspective, and human resource development). A new framework emerged, based on the idea of scenarios, as advanced by Royal Dutch Shell in the 1970s, and on an expanded notion of regional architectures reflecting the new organizational interactions required to plan and manage transportation systems at a regional scale. This framework has been applied in case studies in Houston, Texas, and Mexico City, Mexico, over the past several years, and the methodology has been greatly refined as a result of those applications. How the new ReS/SITE structure addresses the shortcomings in the planning process is indicated, and some further steps in framework expansion and refinement are suggested.