The status of homosexual civilly joined couples: constitutional profiles. The essay examines the background of case law - in particular, of the European Courts and of the Italian Constitutional Court - of the law 20 May 2016, n. 76 («Cirinná Law»), in the so-called «Multilevel constitutionalism» perspective. In the last part ¡t wonder on the impact that similar dynamics could have in Italy on «the double surname statute».