Bureau of International Security and Nonproliferation

Our Mission Preventing the spread of WMD, delivery systems, and advanced conventional weapons capabilities — and rolling back such proliferation where it has already taken root — is the mission of the Bureau of International Security and Nonproliferation (ISN). In close collaboration with other bureaus within the State Department, other U.S. agencies, and a diverse range of international and non-governmental partners, ISN tracks, develops, and implements effective responses to proliferation threats and shapes the international security environment to prevent their recurrence.