Abstract The relationship between the German Constitutional Court and the Court of Justice of the European Union is defined by the German Court’s controversial claim to review whether EU legal acts are compatible with fundamental rights, whether they stay within the limits of EU competences (ultra vires review), or violate the identity of the German Constitution. While the German Court has developed these three review functions in different ways, the recent decision in the case of Honeywell indicates that the three lines of jurisprudence are deeply interrelated. In Honeywell, the Court developed a remarkably restrictive approach to ultra vires review, thereby following a similar path as in its famous Solange jurisprudence with regard to fundamental rights review. Against this background, Honeywell allows to put the different lines of case law into context in a way that reveals parallel patterns as well as differences in the developments. Evaluating Honeywell in this context illustrates that the Court can also be understood as a political actor that tries to maintain and define its role in the process of European integration and in the European system of multi-level governance.