Approved for public release; distribution is unlimited / This thesis analyzes the "updated Petersberg tasks" included in the draft treaty establishing a Constitution for the European Union. The original Petersberg tasks called for forces capable of humanitarian and rescue missions, peacekeeping operations and tasks of combat forces in crisis management, including peacemaking. The updated tasks add conflict prevention, joint disarmament, military advice and assistance, post-conflict stabilization, and support to third countries in combating terrorism. The thesis focuses on the requirements of these tasks and the capabilities of the European Union's civilian agencies and military forces to execute them. It explores the meaning of the new missions, their specific capability requirements, and the prospects for the European Union to meet these requirements. It concludes that the European Union is currently capable of undertaking the missions that require mostly civilian tools or medium-level military forces for their conduct. The European Union does not at present have the relevant capabilities for the missions that demand more advanced military forces. / Major, Hellenic Army