International Courts and the Application of the Concept of "Sustainable Development"

In 1992, at the United Nations Conference on Environment and Development (UNCED), States adopted the Rio Declaration on Environment and Development. Principle 27 of the Rio Declaration states: "States and people shall cooperate in good faith and in a spirit of partnership in the fulfillment of the principles embodied in this Declaration and in the further development of international law in the field of sustainable development." The language of Principle 27 is premised on the view that even at the time of its adoption there existed a body of "international law in the field of sustainable development". However, Principle 27 does not indicate the content of that law, in particular whether it is procedural or substantive or both, or where it's content may be identified. Shortly after the adoption of the Rio Declaration a group of independent legal experts sought to identify its content, on the basis of a review of legal and policy instruments and the international practice of States (which was then, and remains now, somewhat limited). The group concluded that