The Director General of the International Atomic Energy Agency, Yukiya Amano, has announced that the IAEA will henceforth “mainstream” its nuclear security activities. Since the Nuclear Security Summit process ended in 2016 the Vienna-based Agency has resumed its role as the most important multilateral body dealing with nuclear security. While, as expected, it has been unable to replicate the high-level political profile afforded to nuclear security by the summits, it has ramped up its convening activities, adopted new thematic approaches, and consolidated its advisory and technical services. But it is not clear what DG Amano’s statement implied for the future of the Agency's role in nuclear security and for its other mandates. Dr. Findlay will appraise the IAEA's profile since 2016, consider the likely meaning and implications of “mainstreaming” such activity into the Agency's broader portfolio, and propose ways of enhancing the organization's vital contribution in the future.