John Hourdos' expertise is in the area of intelligent transportation systems for traffic control and safety with special emphasis on problems involving traffic modeling and simulation. His current research focuses on Traffic Operations optimization, evaluation of Active Traffic Management systems, and Macro-Meso-Micro hybrid simulation modeling and applications. He is currently the director of the Minnesota Traffic Observatory for which he designed and implemented a unique field laboratory on the highest crash freeway location in the state. In collaboration with Dr. Davis, he has utilized measurements from the I-94 field lab and other sources towards the understanding of vehicle crash causal mechanisms and the development of surrogate measures of safety.