Formulating global environmental change policy is difficult, because the scope of the problems and the stakes involved are large and ill-defined. Framing the Issue of Global Environmental Change is an important initial task. Nevertheless, significant progress has been made on a number of issues in recent years. For example, The Montreal Protocol on Substances That Deplete the Ozone Layer (1987) is a landmark international agreement designed to protect the stratospheric ozone layer from depletion by chemical compounds. The Framework Convention on Climate Change (1992) is the first international treaty to address the problem of anthropogenic climate change. And the 1992 United Nations Conference on Environment and Development (UNCED) placed the issue of global environmental change at the top of the international policy agenda.
A growing scientific literature addresses key global environmental change policy questions. Much of this literature focuses on two topics: Assessing Policy Responses to Global Environmental Change and Formulating International Global Environmental Change Policy. In addition, the role of effective National/Subnational Global Environmental Change Policy as a basis for formulating strong international agreements is being increasingly recognized.