The purpose of this research project is to investigate the accident risk of drivers with high participation in road accidents, focusing on young drivers and motorized two-wheel riders. A traffic data survey throughout Greece will allow for a joint consideration of road accident data and risk exposure data to be carried out. In order to estimate accident risk rates for the above drivers, both European (CARE) and national (SANTRA) road accident databases and analysis tools will be used. The results and proposals of this research project will be exploited by the Ministry of Transport and Communications for the implementation of efficient measures for the improvement of road safety in Greece.