ABSTRACT
In the case of global commons, there are externalities with respect to which countries are both the source and victim of global damage. For example, major transnational efforts are being made for global warming, caused principally by carbon dioxide emissions. It is worth recalling some aspects of economic development since the second world war to counter the idea that peoples of the so-called South are much more responsible for environmental degradation that those of the North. From the point of view of environmental and socioeconomic damage, the size of the externality and the underlying cause determine the number of states involved and the distribution of damage and benefits derived from the externality. According to traditional international trade theory based on the Heckscher-Ohlin approach, free trade leads to achievement of Pareto efficiency. Free-access common property is a different case. Man-made emissions of carbon dioxide account for about 5% of total emissions and most come from combustion of fossil fuels.
