Interest in atmospheric ultraviolet radiation (UV) research has increased considerably since the discovery of the Antarctic ozone hole and after indications of the existence of a similar kind of potential in northern high latitudes. UV measuring and research activities have grown accordingly, including development of new instruments, improvement in quality assurance/quality control methodologies, as well as development of models. Modeling methodologies have been applied for development of spaceborne techniques for estimating the global distribution of solar UV radiation. The European Conference on Atmospheric UV Radiation (ECUV), which was held on June 28 to July 2, 1998 in Helsinki, Finland, brought together 160 scientists from all parts of the world. The Journal of Geophysical Research (JGR) ECUV special issue summarizes 32 papers presented at the conference. New UV trend analyses based on spectral and broadband measurements and modeled UV data for the most recent decades indicate increases of UV-B radiation in various parts of Europe. Additional observational and modeled information on the impact of cloudiness, total ozone, ozone profiles, aerosols, and albedo on ground level UV irradiance has been gathered. The regional UV albedo has been studied over snow-covered surfaces, vegetation, and sea areas by aircraft-based, ground-based, and modeled methods. Further instrument development, improved QA/QC practices, and the application of data correction methods have already taken place but are also clearly needed in the future. Different methods for estimating UV irradiance using spaceborne information have been developed. Additional efforts to improve our understanding of the impact of cloudiness, albedo, and aerosol on UV are expected to improve spaceborne UV retrievals in the future. In Europe the European Commission and national funding agencies have been supporting research projects aimed at understanding the UV climatology in Europe through UV instrument development and intercomparisons, UV database establishment, and UV process, trend, and scenario studies. ¿ 2000 American Geophysical Union