Ultra-wideband (UWB) communications is a new field of technology that has a wide range of applications from range finding to wide bandwidth communications. Ultra-wideband signals are unusual because their bandwidth to center frequency ratio is not small and can be greater than 100%. Recent developments of integrating this technology on a chip have made it versatile and low cost. A number of areas especially those in ITS can benefit by this technology including Automatic Vehicle Identification (AVI), Advanced Traveler Information Systems (ATIS), Advanced Traffic Management Systems (ATMS), Transportation Planning, Collision Avoidance, and Automated Highway Systems (AHS). This paper describes the basics of UWB technology, describes its features, provides background on the technology, and provides some possible applications of UWB to ITS. This paper is not intended to be overly detailed in any one area, but, to provide information about a technology to a wide audience.