AbstractAn increasingly important advantage of nuclear power is its minimal air pollution, in particular the absence of combustion products such as acid rain and carbon dioxide. Developing a consensus about acceptable limits of such pollutants is a slow process that culminates in domestic and international agreements. Therefore, the pace of adoption of new technologies, nuclear power included, is often controlled by the level and intensity of debate, rather than by the technology alone.The state of understanding and consensus about local and long-range transboundary air pollution is therefore germane to the nuclear sector. Progress over the past several decades, mainly between the United States and Canada and within Europe, in developing a more comprehensive and effective international consensus, both informal and formal, is reviewed. There appears to be a trend toward more effective international participation in seeking a less-polluting world, albeit it is punctuated at times by unconcern.