Forests are terrestrial, which concentrates the largest number of life forms and species. Forests play an essential role in the cycles of water, carbon and oxygen. They help to produce, enhance and protect the soil. Hundreds of millions of people derive their livelihoods. They are also the source of much of our medicines. For centuries, men exploit forests, resources and territories to meet their needs. Like other ecosystems, we must now consider how to balance human activities and forests that are essential to the very existence of both companies in industrialized than those of developing countries. Indeed, deforestation and degradation of forest ecosystems weigh both on the conditions of collective life on Climate Change - the destruction of forests is responsible for a significant share of global emissions of greenhouse gases - and that the loss of biodiversity. As the basic functions and services that assure complex and forests are becoming better understood and recognized, they are subject to new forms of protection and management consistent with the objectives of sustainable development.