I am a Senior Research Associate and Project Manager for the Nuclear Information Project at the Federation of American Scientists, where I co-author the Nuclear Notebook––an authoritative account of global nuclear forces and trends. I am also an Associate Researcher with the Nuclear Disarmament, Arms Control and Non-proliferation Programme at the Stockholm International Peace Research Institute (SIPRI). Previously, I worked for the Arms Control, Disarmament, and WMD Non-Proliferation Centre at NATO HQ in Brussels.