The European Security and Defence Union (ESDU) is a concept proposed by Germany, France, Luxembourg and Belgium on 29 April 2003 for the further development of the European Security and Defence Policy (ESDP), first proposed by Dominique de Villepin and Joschka Fischer in 2002[1] and adopted on 17 December 2017.[2] The Security and Defence Union is often equated with the EU's Permanent Structured Cooperation (PESCO).[3]