The European Union (EU) turns increasingly to negative sanctions - a classical tool of international relations and the sharpest expression of the EU’s common foreign and security policy (CFSP) - in response to a variety of norm violations in world politics. This thesis investigates how the EU positions itself and receives a position on the world scene by using sanctions. Regardless of whether sanctions successfully induce target change or not, they signal distance to some actors and proximity to others. In recognition of sanctions’ deeply relational character beyond the sender-target polarity, the thesis juxtaposes the EU’s self-understandings with the perceptions of a significant bystander: the African Union (AU). The thesis exposes patterns of disagreement and consensus as concerns logics of action, autonomy and volume of the sanctions policy, as well as policy linkages between sanctions and other external actions. It combines qualitative and quantitative analysis of European Parliament debates on sanctions between 1999 and 2012 with scrutiny of official documents and semi-structured interviews at the AU headquarters in Addis Ababa. The analysis reveals that self-oriented justifications dominate EU discourse on sanctions. Policymakers are concerned with how to successfully inflict harm on the targets, but mechanisms for making targets change are discussed only exceptionally. Instead, proponents and critics reason about sanctions in terms of the good or bad they do to the EU as a sender, and in particular to the Union’s credibility as an international actor. This thesis disputes the artificial separation between material and symbolic types of sanctions, to instead demonstrate the need to distinguish between primarily self-oriented and primarily target-oriented sanctions. While the AU draws on the European experience in institution building and has high esteem of the EU’s resource capacity, it favours ideational autonomy in its own sanctions doctrine against unconstitutional changes of government. AU perceptions show that the EU has a credibility deficit as an external sender of sanctions. Deep-rooted historical impressions of Europe subsist and are strongly associated with the former colonial powers. The EU’s use of sanctions seems to add to these impressions rather than to challenge them.