This essay places transnational environmental law in an epistemological context. Starting from the general concept of ‘transnational law’ and the specific environmental dimension of ‘international administrative law’, four case histories are presented to illustrate the integrant approach of transnational environmental law. The cases – all arising in the 1970s – deal with transboundary problems of aircraft noise, ocean dumping, river pollution, and marine protected areas. In addition to traditional aspects of public international law in the environmental field, they typically interface with questions of administrative law, private international law, criminal law, and human rights law. The essay advocates a new focus on mechanisms for participation by civil society in the operation and implementation of transnational environmental law.