The European Union's security and defence policy (ESDP) was invented 10 years ago and has been operational for more than five years. During this period the EU has launched over 20 ESDP missions allowing the organization to be engaged in international crisis management in various ways. The coming years will reveal whether the European Union is able to meet its ambitions to carry out a greater number of more complex ESDP missions in higher-risk theatres. While the EU has stepped up the plate to meet these challenges, the three case studies discussed in this article (EULEX Kosovo, EUPOL Afghanistan, EUFOR Tchad/RCA) reveal that the path paved with good intentions might in this case indeed lead to hell. Whereas the new Treaty of Lisbon introduces quite a few institutional changes to the current treaty regime of foreign affairs and security policy, it is questionable whether these innovations will significantly improve the decision-making and leadership on issues of ESDP and, consequently, the effectiveness of the Union as an international crisis manager.