Judicial diversity has become an important concern in many legal systems. The debate has also reached the EU’s highest court, the European Court of Justice (ECJ). Two points have emerged as common ground: First, although disagreement persists as to which identity characteristics are particularly relevant for the ECJ’s composition, the notion that a diverse bench is crucial for the quality and social legitimacy of ECJ decisions is broadly accepted. Second, many agree that, in Luxembourg, practice does not stand up to theory, notably when it comes to diversity in terms of gender, race or the professional expertise of judges. Yet, the question remains: How to turn theory into practice? In the EU, in contrast to many other legal systems, an institution where different claims to representation on the ECJ’s bench can be articulated, which sets up criteria for the Court’s composition and selects candidates with a view to implementing its specific idea of a diverse bench is missing. The ECJ’s composition happens by chance rather than by design. This article investigates the (lack of) institutional prerequisites for thinking about, deciding on and (potentially) enhancing diversity on the ECJ’s bench. Its aim is twofold. First, I seek to understand why a place for ECJ diversity politics is missing in the EU legal system. In the Court’s history, we find at least three different institutions that have been designed to fulfil this role or that have been proposed to do so: the governments of the Member States, the European Parliament, and the expert panel set up by Article 255 TFEU. However, for different reasons – the endurance of state sovereignty, concerns for the ECJ’s independence and a lack of democratic mandate –, they have never successfully exercised this task. Building on these historic experiences, I will argue that in the context of the EU legal system we might not need one institution to do the job. Rather, we should, first, enable politics of diversity to emerge at the European and national levels by creating room for contestation and a choice between candidates for the ECJ’s bench. Second, we should set up a decision-making process where the European Parliament, the governments of the Member States and the expert panel set up by Article 255 TFEU each perform a specific task in thinking about and deciding on the ECJ’s composition. I will sketch this new institutional setup, which could be turned into practice without amending the EU Treaties.