The transformation of family law, presently spreading  throughout the entire land of Europe with different stages of development, questions the law discipline in a multifaceted way.
The scope of this paper is to approach this delicate issue from the point of view of the competences involved: drawing a line between the domestic and EU orders on family matter has been recently proved to be not an easy task. European Court of justice case law and, German and Italian constitutional case law will be placed side by side, in order to single out the challenging questions at stake and the dialogue currently occurring between Courts.
The highly controversial definition of marriage – within the wider territory of family law- will constitute the ideal landscape in which this inquiry will be placed.