Abstract: Scholars interested in researching nuclear security are increasingly expressing the fear that the “important questions” have already been answered. At the same time, recent studies highlight the potential for major limitations on the ability to conduct casual inference on nuclear proliferation in particular, suggesting perhaps that we know much less than was previously believed. Although recognizing these challenges, this article argues that there remain ample opportunities to conduct innovative scholarship on questions of nuclear security. New nuclear challenges bring fresh opportunities for the next generation of research on topics including limited nuclear war; nuclear nonproliferation diplomacy; emerging technology, weapons proliferation and strategic stability; nuclear modernization and arms races; and many other issues. More precise theory, new data, and improved methods of inference also allow researchers to revisit and possibly resolve persistent debates. Although the problems confronting research on nuclear security are serious, they can be addressed. In sum, the questions in this field are so consequential that they deserve the best available analytical attention, even if the resulting answers are not perfect.