A National Special Security Event (NSSE) is an event of national or international significance deemed by the United States Department of Homeland Security (DHS) to be a potential target for terrorism or other criminal activity. These events have included summits of world leaders, meetings of international organizations, presidential nominating conventions and presidential inaugurations. NSSE designation requires federal agencies to provide full cooperation and support to ensure the safety and security of those participating in or otherwise attending the event, and the community within which the event takes place, and is typically limited to specific event sites for a specified time frame.