This book analyzes both NATO’s and the EU’s military crisis management operations and provides an explanation for the fact that it is sometimes NATO, sometimes the EU, and sometimes both international organizations that intervene militarily in a conflict. In detailed case studies on Libya, Chad/Central African Republic, and the Horn of Africa, Claudia Fahron-Hussey shows that the capabilities and preferences of the organizations matter most and the organizations’ bureaucratic actors influence the decision-making process of the member states.