Nuclear security has always been a sensitive area for international cooperation and even for sharing the best practices. States have been guarding the information about their nuclear security measures. With the introduction of terrorism phenomenon after 9/11 incident, the international community has been conscious about possibility of an act of nuclear or radiological terrorism. The US President Barack Obama undertook the task of securing the world from this new kind of terrorism and initiated process of Nuclear Security Summits (NSS)from 2010-2016 in which 53 heads of states were invited. It was the highest forum at which nuclear security was discussed; although, cautiously. NSS entrusted IAEA with the lead role in nuclear security at parallel with the nuclear safety. How the IAEA stands up to its added responsibilities in the post NSS process has to be seen in times to come. Pakistan has also come a long way in perfecting its nuclear security measures especially under the challenging scenario of Global War on Terror (GWOT) being contested within and around Pakistan’s geographical borders. Despite the challenging security environments, Pakistan’s nuclear security measures remained steadfast and not a single terrorist act happened. An appraisal of Pakistani nuclear security approach would be useful for nuclear technology aspirant states as a model of nuclear security best practices.