res judicata embodies a significant trend in this evolving process, whether for overruling legal precedents or introducing new legislative provisions. In one of the oldest civil law systems, the Italian system, the scope of res judicata has expanded significantly, and the primary goal of civil justice reforms and the new jurisprudence has been to reduce multiple litigations. While some differences exist, there is a growing convergence between the two legal systems on the role and impact of res judicata in preventing the relitigation of cases. Res judicata serves as a privileged lens through which familiar elements of both systems contribute to shaping a global pattern of civil justice.