This Diploma Thesis aims to the development of a model for the calculation of economic benefits from the reduction in the number of road accidents and related casualties. After the examination of studies in Greece and based mainly on international bibliography, the optimum combination of methodologies was chosen and subsequently the necessary data from the Greek bibliography and organizations (Statistics, Police, Emergency services, Hospitals, Justice, Insurance, etc.) were collected and cross-checked by experts’ estimations. After the data validation, the particular cost elements were calculated and the related model was developed. In Greece of 1999, the benefits from each life saved in road accidents is as high as 530 thousand euros, whereas the total annual cost of road accidents is as high as 2,4 billion euros. The model developed can be useful for the quantification of benefits from the reduction in the number of accidents and related casualties for other years and other countries.