This report was prepared by the U.S. Department of Transportation's (U.S. DOT) John A. Volpe National Transportation Systems Center (Volpe Center) for the U.S. DOT's Intelligent Transportation Systems (ITS) Joint Program Office. The Volpe Center study team consisted of Allan J. DeBlasio, the project manager, Amanda Zamora, Frederick Mottley, and Robert Brodesky from EG&G Technical Services; Margaret E. Zirker and Michelle Crowder from Cambridge Systematics Inc.; and Terrance J. Regan, Kathleen Bagdonas and Dan Morin from Planners Collaborative. Vince Pearce is the U.S. DOT manager of the review.