This thesis analyzes EU international climate policy discourses around the adoption of the Kyoto Protocol, its entry-into-force and the COP15-negotiations in Copenhagen. Using EU-press releases and employing Hajer’s argumentative approach, the main focus lies on discursive shifts and self-representation. In addition evidences of discourse institutionalization are presented. The thesis also gives an extensive insight into the theoretical underpinnings used in the analysis and provides references to the actual EU-climate-policy around and during the analyzed timeframes. The thesis finds considerable discursive shifts, including a changing role of science, global responsibility and the economy. Findings also include the self-representation of the EU changing from an emerging to an established and powerful actor but with a sharp rupture after COP15.