Harmonization and Unification of International Commercial Law

Abstract This chapter traces the history and development of harmonization and unification efforts in international commercial law. It examines the evolution and influence of key instruments and institutions, including the CISG, UNCITRAL, UNIDROIT Principles on International Commercial Contracts (PICC), and the Hague Conference on Private International Law. The chapter analyses their contributions to uniform sales law, contract law, arbitration, mediation, and electronic commerce, and addresses complementary and divergent functions among these regimes. Regional initiatives in Africa (OHADA), Europe (PECL, DCFR), Asia (PACL), and Latin America (PLACL) are discussed alongside trade terms, model contracts, and the modern lex mercatoria. Finally, it explores the ongoing debate regarding the role of regional versus global instruments and the use of lex mercatoria as governing law in international contracts.