The ALARA (As Low As Reasonably Achievable) principle consists in taking the most effective protection measures considered to be “reasonable”, irrespective of the exposure levels. Application of this principle weighs the protection resources against the level of protection in order to attain the best possible protection considering the economic and social conditions. Thus, under the aegis of the European Commission, the ALARA network (20 countries) identifies, assesses and selects the best radiation protection actions for keeping the exposure of workers and the general public at a level that is as low as reasonably achievable.