With the next Nuclear Security Summit to take place in the United States in 2016, a window of opportunity will be opened by next year’s NPT Review Conference, which will allow the world to address the issue of nuclear security in a long-term, inclusive manner. What is most needed in the run-up to the 2016 NSS is a process that advances global action to address the nuclear threat comprehensively, including by ensuring that the CTBT enters into force.