This paper traces the stages of the infringement procedure under Art. 258 TFEU [Treaty on the Functioning of the European Union] and seeks to explain how the European Commission has prioritized its use. The paper has two substantive sections. Part 1 describes the stages of the infringement procedure, moving from the pre-judicial stage to the judicial stage and post-judgement compliance. Part 2 describes why the Commission must prioritize its enforcement decisions and seeks to understand how the Commission chooses which cases to pursue. The paper describes several important cases where the Commission’s political incentives were heavily aligned with its decision to start infringement proceedings. The cases demonstrate there is some possibility that the Commission has used the infringement procedure to achieve political objectives.