TRB’s Transportation Research E-Circular 114: Research Opportunities in Radio Frequency Identification Transportation Applications summarizes a conference by the same title that was held October 17 to 18, 2006, in Washington, D.C. This conference focused on current and future research on radio frequency identification (RFID) technologies in transportation applications, which include the tagging of containers, pallets, individual packages, and building equipment and components; vehicle collision avoidance; electronic preclearance of vehicles and individuals through security checkpoints; and electronic toll collection.