This publication is the proceedings of the 12th Congress of the International Radiation Protection Association (IRPA), organized by the Argentine Radiation Protection Society (SAR) and co-sponsored by the International Atomic Energy Agency (IAEA), the World Health Organization (WHO) and the Pan-American Health Organization (PAHO). The congress brought together a broad range of professionals from around the world to discuss the promotion, enhancement and strengthening of radiation protection worldwide. To attain these general policy objectives, IRPA12 was arranged in three distinct main fields, which were divided into 10 scientific areas including a total of 38 topical sessions. The conclusions of these special topical sessions are synthesized and the results of the round table discussions are also presented in this publication.