The outgoing tide of EU law will be Britain’s most significant constitutional change in recent times. In an era of uncertainties, the UK Supreme Court proved to be a guardian of the constitutional role of Parliament. The case of Miller, decided in the UK Supreme Court in 2017, proved that point. The highest court in the UK has therefore gained an important place in the global community of Constitutional Courts. This global community finds its legitimacy in the recognition of common values as well as the recognition of national variations. This article analyses to which extent common values, and in particular those found in German law, have influenced decisions in the House of Lords and UK Supreme Court. To do so, the author analyses decisions by the House of Lords and the Supreme Court and extrajudicial speeches by the Justices of the Supreme Court for references to German constitutional law. It identifies and maps the themes that have attracted the attention of the justices of the Supreme Court. More recently, the UK Supreme Court has referred to judgments and extrajudicial writing by German Constitutional Court judges. This was in the context of constitutional questions relating to the tension between membership within the EU and national identity, a theme which has occupied German judges for some time. As well as that, the interpretation of the European Convention on Human Rights has sparked an interest in German jurisprudence, in particular in the principle of proportionality.