The fourth Nuclear Security Summit (NSS 2016) took place on March 31 - April 1, 2016 in Washington D.C. President Nursultan Nazarbayev addressed the Summit saying that Kazakhstan is regarded as one of the twenty countries to have the highest level of security of the nuclear facilities and materials. Within the framework of the NSS 2016, Kazakhstan and the U.S. adopted the joint statement on cooperation in the sphere of non-proliferation and nuclear security. The sides also reiterated overall commitment to continue practical cooperation in that sphere.