Natural rubber produced by Hevea brasiliensis is an economically important crop for millions of small growers in tropical countries. Tree crop cultivation is an ecologically sound form of land use in the humid tropics. The establishment of rubber plantations after forest clearing allows for permanent soil conservation measures such as terracing of hills and drainage of swamps as well as development of mixed under-storey vegetation. The utilisation of rubber wood after the productive life of the tree is over reduces the pressure for logging in primary forest areas. Hevea culture is a sustainable, renewable agro-forestry system with a closed nutrient ecosystem and a planting cycle of approximately 30 years. The biomass accumulation of a mature Hevea ecosystem is equivalent to native rain forest system, therefore it is likely that the levels of carbon dioxide, oxygen and water vapour recyled in rubber plantations are approximately equal to those in rain forests. Production of the rubber polymer molecule within Hevea trees is by the non-polluting process of photosynthesis. Compared to synthetic rubber production which consumes petroleum feedstock in large, energy intensive, manufaturing plants, natural rubber is an environmentally friendly industrial raw material.