The aim of this paper is to explain how the European Union’s common strategy for theCommon Foreign- and Security Policy (CFSP) will change with the implementation of the Treaty of Lisbon. A comparative case study and qualitative method is used. On the basis of Smith’s theory of institutionalization we will analyze two member states: France and Denmark. Our aim is to see which standpoints these countries have taken concerning the CFSP. We have chosen, in order to analyse the inner and outer factors, to use the liberal intergovernmental “two level game” theory as a theoretical approach. The purpose of the CFSP is to gradually increase the sovereign states’ foreign policy cooperation. The aim of the CFSP is to become an international visible and active player that represents the people of the European Union. At the moment the CFSP is an intergovernmental part of the EU, however there are presentiments that this will change and that CFSP will achieve supranationality. In conclusion, the results of the case study shows that Denmark is aiming for the CFSP cooperation to remain on an intergovernmental platform. France is aiming toward supranationality and a stronger cooperation within the CFSP. In time, with the full implementation of the CFSP, the EU will be able to compete on a global platform.