There has been mounting environmental criticism of the livestock industry. Ruminants such as cattle have been implicated as significant contributors to greenhouse gases and it is argued that it is less food efficient to feed plant matter to livestock rather than have humans consume it directly. Furthermore, in many cases, livestock destroy natural vegetation and cause accelerated soil erosion as a result of overstocking often for socio-economic reasons. In other cases, such as in the Amazon rainforests have been cleared to provide pastures for cattle. Writers such as David Pearce and Charles Perrings have criticised socio-economic arrangements in Africa, e.g., in Botswana where the livestock industry involves common-property and forms of government assistance for grazing which are environmentally damaging. Furthermore, intensive livestock farming particularly in developed countries is a major source of pollutants. While some of these criticisms are justified, it is pointed out that there are counter considerations and that the livestock industry appears to have been discriminated against in some developing countries. The final portion of the paper reviews the development of the livestock industry in Thailand, the environmental issues raised by this development and the sustainability of the industry including aspects of animal health and diseases for its sustainability.