Principles of civil procedure under ELI-<scp>Unidroit</scp> rules: convergence through a uniform approach to procedural obligations?

Abstract Harmonizing civil procedure across different legal systems is a complex challenge. The European Law Institute (ELI) – International Institute for the Unification of Private Law (Unidroit) project, From Transnational Principles to European Rules of Civil Procedure, demonstrates that meaningful convergence is best achieved not through mandatory rules but through the voluntary adoption of well-designed procedural models. Genuine procedural convergence does not entail merely copying isolated legal rules but, rather, embracing a common procedural model rooted in a shared legal ideology. This shared foundation is best established through a unified approach to procedural principles. This article examines the constellation of procedural principles developed by the Obligations Working Group of the ELI–Unidroit project, which positions the principle of loyal cooperation as the overarching procedural principle. This principle underscores the joint and shared obligations of all participants in civil litigation—courts, parties, and lawyers—to collaborate in ensuring a fair, efficient, and accessible dispute resolution process. Other procedural principles function either as clarifications of this core principle’s goals and values or as methods and tools for achieving them. To illustrate how this common understanding fosters convergence, the article analyses Croatia’s recent procedural reforms, which reflect the ELI–Unidroit’s approach to procedural principles. Examples of converging norms include the redrafting of the principle of loyal cooperation in Article 10 of the Croatian Code of Civil Procedure and the introduction of a pre-procedural obligation to attempt settlement in the new Act on Amicable Dispute Resolution. Additionally, the 2022 Code of Civil Procedure amendments incorporated a modernized approach to illegally obtained evidence, aligning with the principle of proportionality and Rule 90 of the ELI–Unidroit Rules.