The global nuclear order is facing unprecedented challenges with Russia, North Korea and Iran all testing the limits of nuclear non-proliferation. The landmark Nuclear Non-Proliferation Treaty marks its 50th anniversary next year. Will it be able to survive in its present form? This month, as Carnegie brings together 800 experts for its nuclear policy conference in Washington, Tom Carver spoke with Carnegie’s James Acton and Toby Dalton about the nuclear nonproliferation agenda. James Acton is co-director of Carnegie’s Nuclear Policy Program. A physicist by training, Acton was a winner of the competitive Carnegie Corporation of New York grant on New Technologies and the Nuclear Threat that funds his ongoing research into the escalation implications of advanced conventional weapons. Toby Dalton is co-director of Carnegie’s Nuclear Policy Program. An expert on nonproliferation and nuclear energy, his work addresses regional security challenges and the evolution of the global nuclear order. From 2002 to 2010, Dalton served in a variety of high-level positions at the U.S. Department of Energy, including senior policy adviser to the Office of Nonproliferation and International Security. He also established and led the department’s office at the U.S. embassy in Pakistan from 2008-2009.