This paper identifies and introduces the emerging principles, standards and other forms of soft law that form an increasingly comprehensive set of principles for guiding international society toward sustainable development. Although states may currently differ on the legal status of specific principles discussed in this paper (i.e., whether a principle is on the continuum of emerging international law or generally recognized as existing international law), these principles nonetheless frame the current debate for international environmental policy-making and are increasingly important for discussions of trade and the environment. Part 2 of this paper describes the development of the sustainable development concept and its implications; Part 3 describes the duty to cooperate in environmental protection; Part 4 describes the duty to avoid environmental harm· and Part 5 describes the duty to compensate for environmental harm. Part 6 describes the status of natural resources within national boundaries and the global commons.