For the past twelve years, the use of Global Positioning System (GPS) devices has been under development as a potential method to measure the travel behavior of individuals, in preference to the use of any of variety of self-report methods, such as travel diaries and face-to-face interviews. Within the past year or so, devices have progressed to the point that they are readily able to be used as personal tracking devices, and some years of development of software has taken place for processing the data collected by means of personal, portable GPS devices. In work that began at LSU has continued for the past 8 years at the University of Sydney, Professor Stopher and his associates have pioneered the use of GPS surveys to measure travel behavior. In this seminar, Stopher will describe and demonstrate the people to carry the devices with them. The devices collect travel data on a second-by-second basis. This produces large data files that must be processed to obtain information about individual trips from an origin to a destination. Using a number of rules that will be described in the seminar, the stream of data points are first divided up into specific origin-destination movements. Then, using various GPS layers and additional rules, the mode of travel of each of these movements is inferred, along with the trip purpose. The rules that are used in this process will be described. Results of the processing will be shown to indicate the nature of the final processed information. The University of Sydney in a team with a some of  US firms, is about to commence the first large-scale GPS household survey every undertaken, with 4,000 households to be surveyed in Ohio. The seminar will conclude with a brief discussion of this commencing project and some of the additional advances that are expected to result from it, especially in the addition of Artificial Intelligence applications to assist the current processing software.