Russell Errol Train served as the second EPA Administrator, from September 1973 to January 1977. During this time, he supported EPA's expansion of interest in international affairs; the approval of the catalytic converter to achieve Clean Air Act automobile emission reductions; the implementation of the Toxic Substances Control Act (TSCA) and the National Pollutant Discharge Elimination System (NPDES); and EPA's work to balance the demands of the energy crisis with environmental issues.

After leaving EPA he served as President of the World Wildlife Fund-U.S. (WWF - U.S.) from 1978 to 1985, and as its Chairman from 1985 to 1994. During 1988 he also worked as Co-Chairman of Conservationists for Bush, and from 1990 to 1992 as Chairman of the National Commission on the Environment. From 1994 to 2012, Train was Chairman Emeritus of WWF - U.S.

Earlier in his career, Train served from 1949 to 1956 as Attorney, Chief Counsel, and Minority Advisor on various Congressional committees, then from 1956 to 1957 as Assistant to the Secretary and Head of the Legal Advisory Staff for the Treasury Department.

Train was a Judge for the U.S. Tax Court from 1957 to 1965; President of The Conservation Foundation from 1965 to 1969; Under Secretary of the Department of the Interior from 1969 to 1970; and Chairman of the newly formed Council on Environmental Quality (CEQ) from 1970 to 1973.

Train served as Trustee Emeritus for the African Wildlife Foundation which he founded in 1961, and as a member of the Council on Foreign Relations, The Washington Institute on Foreign Affairs, and the Atlantic Council.

Train was born in 1920 in Jamestown, Rhode Island, and graduated from Princeton University (B.A., 1941) and Columbia University Law School (J.D., 1948). He was married and had four children.