This volume contains the contributions to the Gulf Research Center workshop entitled: “Gulf Cooperation Council (GCC) Relations with Post-War Iraq: A Strategic Perspective,” held during the July 2013 Gulf Research Meeting in Cambridge, UK. The papers examine the history and future of the often fractious relationship between Iraq and the GCC countries. The backdrop is the US dominance of security arrangements in the Arabian Gulf region for most of the post-war period. Prior to the new millennium, the region’s major security threat was perceived to be the mounting rivalry between a GCC-US camp on the one hand and an Iranian camp on the other. Some semblance of equilibrium had been achieved through the late 1990s, but the US invasion of Iraq in 2003 created new fault lines. In the invasion’s aftermath, regional peace was maintained by the overwhelming presence of US troops both in Iraq and in the GCC more generally. The 2011 withdrawal of US troops from Iraq plunged the region into a state of disequilibrium, and current developments suggest a trajectory of mounting instability.