The present introduction offers a concise overview of the Grand Chamber of the Italian Supreme Court's (Corte di Cassazione a Sezioni Unite) decision of 5 December 2023, No. 33954, which provides its interpretation of the subsidiarity of unjust enrichment. In particular, despite the reaffirmation of the rationale of legal certainty, this decision serves to mitigate the strong understanding of subsidiarity that was previously dominant in Italian law. The Grand Chamber's arguments are examined through the lens of the commentaries provided by Anglo-Saxon, Belgian, Dutch, French, German and Spanish perspectives. In conclusion, an evaluation of the subsidiarity rule is provided.
European Review of Private Law