The organisation of the judiciary is close to the heart of any system of government. For that reason, the EU Member States have largely resisted surrendering regulatory power over judicial procedures and remedies to the Union level. In the absence of legislative action, it has fallen upon courts to manage the enforcement of Union rights through national procedures. In this context, the preliminary reference procedure offers a deliberative setting allowing courts at state and Union level to enter into dialogue over the degree of Europeanization of this “sovereignty-sensitive“ field. Relying on an empirical study of the exchanges between referring courts and the CJEU, the paper examines how courts at both levels respond to the responsibility of balancing national autonomy against European integration, offering new insights on the way in which courts deal with politically sensitive matters in every-day adjudication.