In recent years the issue of terrorism has become increasingly conspicuous in domestic and international politics. Due to the transnational nature of the threat, regional institutions have become an important pillar of states’ political strategies to counter terrorism. In fact, a major aim of the Shanghai Cooperation Organisation (SCO), a regional organisation established in 2001 by China, Russia, and the Central Asian states of Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan, has been to fight the so-called ‘three evils’ of terrorism, separatism, and extremism. The pre-eminence of concerns regarding these issues is easily discernible considering the geographical proximity to Afghanistan and Pakistan, the occurrence of terrorist attacks on SCO member states’ territories, and the fact that thousands of SCO nationals have recently joint terrorist groups such as the so-called ‘Islamic State’. Arguing that the threat of terrorism and instability in the SCO region has risen to an unprecedented height, this doctoral dissertation aims to examine China’s role within SCO decision making in regard to counterterrorism. This will contribute to a better understanding of security cooperation of non-democratic regional groupings, as well as, more specifically, provide insight into SCO counterterrorism efforts and China’s role as the most powerful actor therein.