The Canadian Coalition on Acid Rain (1981–1991) helped obtain agreements between Canada and the United States to reduce sulfur dioxide and nitrogen oxide emissions. The Coalition was formed in 1981 and lobbied the Canadian and American governments for emissions controls to stop acid rain. Its high-profile campaign in Washington, D.C. was unprecedented for a Canadian organization at that time. It became Canada’s largest environmental organization and helped to keep acid rain Canada’s top environmental priority throughout the 1980s.