The EU has since 2003 carried out six military operations.  This thesis seeks to determine the circumstances under which the EU will, or will not, undertake military operations.  It does so through the study of two main cases of EU military operations: the case when an operation was planned in the Lebanon war 2006 but did not occur, and the positive case of EUFOR RD Congo that same year which did occur. Three additional cases are presented. An analytical tool built on the techniques of defence planning and concepts derived from the scholarly literature is applied to the cases for the purpose of identifying the main driving and inhibiting factors behind the operations. The functional  theme of the use of force and the organizational theme of the multilateralisation of intervention serve as the main scholarly concepts.  The interaction between the intervener and the local actors, as well as between political and resource factors, is introduced in order to create an integrated framework for the analysis of the dynamics at play in the EU’s use of force. The limitations to the "jus bellum" tradition is noted in the analysis of the EU´s operations that have situated themselves in a low-to-middle bandwidth in terms of interests and risks at stake. Among the findings, the growing importance of local actors in shaping the room for the EU´s deployment of military force stands out, as do resource constraints, in the EU´s case primarily in the form of its limited command and control structures but also through the overstretch of the global pool of expeditionary forces felt around 2006. As seen from the organizational perspective, the EU´s first military operations can best be understood in the context of the increasing role of regional security providers in an unofficial division of labour with regard to the multilateralisation of intervention. / <p>Avaliable in revised and extended version: "The EU and Military Operations. A comparative analysis".</p><p>http://www.routledge.com/books/details/9780415821360</p><p> </p>