This paper investigates the role played by the Gulf Cooperation Council (GCC) in mediating disputes since its creation in 1981 to 2011, the year of the outbreak of the ‘Arab Spring’. It analyzes the contributions of the GCC as a conflict mediator by crosschecking this sub-regional group’s institutional structure and policy approach, and presents two major findings. Firstly, the GCC was hardly designed as a conflict mediator, given that the Gulf Arab states created it as a vehicle to respond to intra-Gulf and external security threats and challenges. Secondly, in order to promote its foreign policy independence and boost its regional and global diplomatic profile to ensure its security and survival in the dangerous environment of the Gulf region, it is Qatar that has extensively attempted to mediate conflicts in Lebanon, Yemen and Sudan, with varying degrees of success, under the banners of the GCC and the Arab League. Finally, the paper presents a series of policy recommendations, based on critical insights from Qatari mediation experiences, to enable the GCC to be a proactive dispute mediator.