In 2015, the European Union launched the Energy Union in order to reduce fragmentation in European energy policy and boost Europe’s energy transition. This chapter analyses whether the Energy Union, as a policy package, constitutes a coherent whole and whether its distinct components are being pursued in a coordinated manner. We use a simple policy-analytical framework by which the policy components are juxtaposed in a screening matrix. The interactions between the Energy Union policy components are assessed according to a novel typology for understanding interactions and coherence in the 2030 Agenda, with policy interactions ranging on a scale from cancelling to indivisible. Our assessment shows that the interactions are often complex and sometimes vary depending on the time frame. We identify two key hotspots: the relationships between energy security and energy efficiency and between energy security and decarbonisation.