This paper describes the elements of success in a major research project undertaken by a federal laboratory, in partnership with state and local transportation agencies, and sponsored by the Federal Highway Administration, U.S. Department of Transportation. The research project is TRansportation ANalysis and SIMulation System (TRANSIMS), the largest civilian transportation simulation research and development project in the history of the United States, or any other nation. This paper explores why the project succeeded, beginning with the concept and design in November 1991, through initial federal funding in March 1993, to the research program and products today. The elements of success may be helpful to other state and federal research initiatives. Understanding success is particularly important in the design and conduct of research that is high risk and high payoff. This is the type of research well suited to the federal laboratories. TRANSIMS is one example of how to effectively engage the research capabilities of our federal laboratories to meet an urgent transportation need.