37

This paper deals with the question of international co-operation in the light of global environmental problems, such as climate change, the deterioration in the ozone layer, and, to a lesser extent, acid rain. More specifically, we evaluate the economic literature on this subject in light of the main features of this type of problem and the issues they raise. These are: time, heterogeneity of countries, uncertainty, and the influence of lobbying groups. An analysis of the theoretical literature associated with these features leads us to note the limitations of existing literature.