The 2012 Nuclear Security Summit was a summit held at the COEX Convention & Exhibition Center in Seoul, South Korea, on March 26 and 27, 2012. It was the second time the conference was held after the 2010 Nuclear Security Summit. The summit series discusses international cooperative measures to protect nuclear materials and facilities from terrorist groups. Fifty-eight world leaders from 53 states and four international organizations, including the United Nations, International Atomic Energy Agency, the European Union and INTERPOL, participated. The main issues discussed were: