The Unidroit Principles on International Commercial Contracts and sustainable development.

The article examines the role of the International Institute for the Unification of Private Law's (Unidroit) Principles on International Commercial Contracts (UPICC) in promoting sustainability standards within multinational corporations' contracts. It highlights how sustainability clauses and codes of conduct, increasingly included in international commercial contracts and supply chains, address environmental, social, and governance (ESG) concerns but face challenges in enforcement under traditional contract law. The UPICC, through mechanisms such as contextual interpretation, good faith, recognition of trade usages, and incorporation of mandatory rules, offers flexible tools to transform these often non-binding sustainability commitments into enforceable contractual obligations. The article argues against radical changes to the pacta sunt servanda principle, instead advocating for the use of existing contract law principles within the UPICC to ensure compliance and cooperation among parties, thereby supporting the broader sustainability agenda in transnational commercial transactions.