Today the Gulf Cooperation Council States find themselves surrounded by a region plagued by a growing number of threats. The GCC states are embroiled in a difficult conflict in Yemen, Iraq is on the constant verge of collapse, Syria has collapsed and Jordan and Lebanon face immense pressures from the flow of refugees and internal troubles. The turmoil has given rise to groups like ISIS, Al-Qaeda branches and a swarm of Iran backed proxy militias, each working to fill the vacuum created by the various forms of strife. For the GCC, there is no threat greater than the other and each must be simultaneously dealt with. Though, out of the all the threats the GCC faces, terrorism, especially in the form of ISIS/Al-Qaeda operation pose a menacing problem. The threat of ISIS (and similar groups) is especially worrisome since it effects the GCC internally (internal attacks/consequences) and externally. Even after an international coalition was formed by the US to attack ISIS, the group has proven resilient, still holds vast swathes of land, has conducted attacks all over the Middle East and has even managed to spread through to North Africa, Afghanistan and Pakistan. This chapter will not attempt to address in detail the ideological underpinnings of the Islamic State of Iraq and Sham, since there is plenty of work undertaken in academia which discusses and questions the religious origins of the group. Instead, this chapter will analyze how the group has posed as a threat to the GCC so far, how different has it been than the different terrorist groups and attacks that have occurred in the GCC. It will also analyze the effect of the attacks carried out by ISIS, what its intentions were/are. The GCC is no stranger to the threat of terrorism and has faced various forms successfully since its inception. This continues to be the case today as well, but with the threats increasing all around, the room for error increases. Therefore, an analysis of how the GCC and its citizens have reacted, how effective it has been and what is further required by the GCC in order to face this threat is essential. The GCC bloc is the only secure and stable group of countries in a region beset with violence and it is in their hands to lead the way in tackling terrorism and its root causes directly. As this chapter will show, the GCC requires a two front strategy in dealing with the threat from groups like ISIS, the first being internal and the second internal. As long as the external threat of ISIS exists, it will continue to effect the GCC states internally in some way, form and shape.