Leonidas Ntziachristos is an Associate Professor at the Lab of Heat Transfer and Environmental Engineering at Aristotle University Thessaloniki, Greece. He holds a Ph.D. in Mechanical Engineering in the area of vehicle emission characterization. His current research interests are on gaseous and aerosol emissions characterization from mobile sources, and he has significant experience conducting research for European-sponsored projects. He has been responsible for the development of the COPERT emission calculation tool on behalf of the European Environment Agency and the EU Joint Research Centre. He currently serves as a member of the Executive Board of ERMES and co-chairs the transport expert panel of TFEIP. He has been chosen as a Finnish Distinguished Fellow and currently spends part of his time at the Tampere University of Technology, Finland. He has been the author of more than 200 scientific and technical papers.