The references to the «constitutional traditions common to the Member States» (CCTs) in Article 6(3) TEU and in the Preamble and Article 52 of the Charter of Fundamental Rights of the European Union originate in the case law of the Court of Justice of the European Union. Examining almost five decades of case law on the issue, this article explores three main research questions by providing a quantitative analysis of 100 judgements handed down by the CJEU. Primarily, the article examines whether the Court tends to refer to CCTs as a rather supple «source of inspiration» to corroborate the protec- tion of fundamental rights, or as an autonomous source of fundamental rights. Second, the paper seeks to analyse whether it draws upon those traditions by engaging in an extended search into their individual national manifestations (and, if so, which of these influence the development of EU law most often). Last, the article investigates the fundamental rights in connection to which reference has been made most often to the CCT clause. The article concludes that CCTs are a potential counterpart to the notion of «constitutional identity», showing that Europe s constitution is not disconnected from the constitutions of its Member States.