The Lisbon Treaty marks the end, at least for the foreseeable future, of the project of a European Constitution. But does it also mean a rejection of the tradition of Western constitutionalism? The author addresses the question outlining, first, the main elements of the modern Western conception of constitutionalism. In a second step the analysis concentrates on which of these contents are nonetheless present in the Lisbon Treaty. The claim is made that, regardless of its persistent deficits, the basic law of the EU has to be considered as belonging to the legacy of constitutionalism, paving the way to a constitutionalism beyond national constitutions. Lastly, the inquiry is concluded with some considerations on the main features of a multilevel public law system.