The study of business interests adds an important dimension to our understanding of the development of international environmental agreements. The contrasting role of business interests in the cases of ozone depletion and climate change is critical to explaining why climate change is a much more difficult issue for the international community to tackle. In the case of ozone depletion, industry concentration and the technological factors provided incentives for industry leaders to invest in alternative products and processes. By contrast, fossil fuel substitutes present a long-term strategic threat to the major sectors that produce and use these fuels. Where relatively few actors were involved in ozone depletion, it will be much more difficult to craft an agreement that is acceptable to the broad range of industries affected by climate change. However, business does have substantial influence over the timing and shape of international environmental agreements, even when there is considerable disunity within the business ranks.