International Environmental Law after Half a Century

This symposium assesses the evolution – or, more neutrally, the trajectory – of international law as it relates to the environment in the last half-century. In the decades since the 1972 Stockholm Conference on the Human Environment and until 2025, a watershed for climate litigation (but for little else), the development-environment equation that haunts every environmental negotiation, every instrument and much of the case-law became only more polarized. In this introductory article, I discuss three main aspects of this assessment, as they arise from the contributions to this symposium: (i) the case for reconsidering the overall retrospective narrative of international environmental law; (ii) the possible reasons explaining its inability to address humanity’s geological impact; and (iii) the role of international law in relation to the balancing of the terms of the development-environment equation. The purpose is not descriptive; it is analytical, and sometimes critical. It is an effort to provide the context that is most relevant for an understanding of these contributions.