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About Us
updated 13 Aug 2025

These summarize & link to the most important information needed by most website visitors.
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The Treaty on the Prohibition of Nuclear Weapons

The Study Group was founded in 1989 by Greg Mello and others who met regularly and organized public meetings in Los Alamos and Santa Fe to discuss nuclear policy and related issues. In 1992, the Study Group began work as a full-time staffed organization. Since then, we have contributed thoughtful popular and policy leadership on Department of Energy (DOE) and National Nuclear Security Administration (NNSA) weapons laboratory and warhead issues, in which we have considerable – in some respects unparalleled – expertise. In 2003, Trish Williams-Mello brought her skills and her experience in citizen oversight of the Pantex nuclear weapons plant into our full-time staff.

We have conducted hundreds of public meetings, and several hundred briefings on Capitol Hill. We are strictly nonpartisan and factual – which is now more important than ever – and we anchor policy details in a broad historical and technical perspective. We focus on practical outcomes. We have wide technical, legal, and public education experience as well as strong academic and work histories in science, engineering, law, and organizing. We draw on a wide range of other experts as needed.

We have been quoted in thousands of newspaper articles and interviewed on hundreds of radio and TV programs. Greg Mello has been published in the New York Times, Washington Post, The Bulletin of the Atomic Scientists, Issues in Science and Technology, in the New Mexico press, and elsewhere. We have won environmental, civil rights, and freedom of information lawsuits. We have blocked major nuclear warhead infrastructure projects at Los Alamos National Laboratory (LANL), in which efforts we have had to work against the arms control community and the New Mexico congressional delegation. Our litigation led to the only cancelled nuclear weapons project during Barack Obama's presidency. We were named one of the nation’s “top ten small green groups” in 2011, one of eleven “favorite groups” in 2013, and one of 20 organizations in the "Thin Green Line: 20 Groups Standing Between You and Doom" in 2016 by Counterpunch.

Our analyses of U.S. nuclear weapon modernization have been significant contributions at Nuclear Nonproliferation Treaty (NPT) review and preparatory conferences and other international fora since the 1990s. We were significant participants at and between all international fora leading to the successful creation of the Treaty on the Prohibition of Nuclear Weapons (TPNW). Greg was a Research Fellow in the Princeton Program on Science and Global Security (PSGS) in 2002 and in 2017-2020 PSGS contracted with the Study Group to produce articles for the International Panel on Fissile Materials (IPFM) blog as well as congressional workshops on plutonium warhead core (“pit”) production.

We have also led dozens of public workshops on energy and climate policy and related economic issues, and in 2017 devoted much of the summer to training young people in energy and climate policy.

  • Mission and Method
  • Board and Staff
  • History
  • Brochure, 2006
    "[W]e as a nation must undergo a radical revolution of values...A nation that continues year after year to spend more money on military defense than on programs of social uplift is approaching spiritual death." – Martin Luther King, Jr.
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