The primary objective of the Union Internationale des Radioecologists (UIR) remains the exchange of information in the field of radioecology and related subject areas particularly in relation to major (accidental) releases of radioactive materials. This objective is not restricted to information on the transfer of important radionuclides in the environment but includes information which can aid in understanding the impact of radiation exposure on populations of living organisms and ecosystems. The objective is being met by a series of task forces which are collating available information on specific topics and providing syntheses which can be applied to the design of new research programmes and for assessing overall priorities in radioecology. UIR also continues to provide a mechanism for the training of young scientists and for maintaining links with radioecologists in non-EU countries via a series of steering committees, including the organization of workshops and the preparation of a textbook on radioecology. UIR, through its international membership, provides a mechanism for the dissemination of information in the radioecological sciences and for the bringing together of interested parties in the exploitation of new developments in related modelling and assessment activities.