Thomas Cochran has been working with the Natural Resources Defense Council since the 1970s to stop the use of nuclear power, particularly the kind that uses most of the potential energy and produces the least amount of radioactive waste. Harold A. Feiveson is Senior Research Policy Scientist at Princeton University's Center for Energy and Environmental Studies. Dr. Feiveson's principal research interests are in the fields of nuclear weapons and nuclear energy policy. Frank von Hippel is Professor and Co-Director of Program on Science and Global Security at Princeton University and Woodrow Wilson School of Public and International Affairs.: This article chronicles the rise and fall of fast-reactor research in the United States.