Tis report focuses on key issues discussed during the third and fourth meetings of Regional, Subregional and other International Organizations on Preventive Diplomacy and Mediation hosted respectively by the League of Arab States (LAS) in 2014, and the European Union (EU) in 2015. Te common thread of discussions focused on a key principle of the UN Guidance: Coherence, Coordination and Complementarity in mediation processes, with particular focus on contexts in which one or more regional organizations are involved.