Looking at integrational history, common energy policy seems to be, besides trade policy, one of the earliest ‘European’ issues. Nevertheless, on paper, it became a policy area with its own title, but only since the 2009 Lisbon Treaty. In this development the discourse on energy policy was shaped by three frames – security (of supply), sustainability and competitiveness, which received different amounts of attention and were used by different actors in different time periods, and they guided European action in different ways. This contribution will analyse the development of the energy frames within the integration process. Thus, the following questions will be addressed: Which composition of frames shapes EU energy policy in different integration periods? Which actors and actor coalitions support which frames in the European energy discourse? What are the consequences for the integration process?