Intensive mixed-use development projects around transit stations, commonly known as transit-oriented development or TOD, have moved into the mainstream debate over metropolitan growth and development. Such projects are generally considered to have positive benefits in terms of economic development and transit ridership. However, this report finds that true, comprehensive TOD projects remain relatively scarce in this country and that often projects labeled “transit-oriented” are merely “transit-related,” in that they do not take full advantage of their potential to also be environmentally sustainable and socially just. In order to reframe the debate, this paper offers an expanded definition of TOD that focuses primarily on functions and outcomes rather than on physical form and project configuration. It identifies challenges that must be addressed and offers policy recommendations to achieve optimal TOD projects.