Rangelands occupy about 50% of the world’s land area. They are ecologically and economically as important as rain forests and in even greater danger of degradation and disappearance. This paper reviews the definitions and distribution of rangelands and describes their global environmental importance in terms of erosion control, carbon storage and methane emission. Condition and degradation of rangelands are defined and discussed and it is argued that soil protection and carbon storage can be increased and methane emission per animal decreased by conservative use and improvement of rangelands, whilst at the same time alleviating hunger and malnutrition in developing countries. It is concluded that policies should be adopted by national governments and international deve-lopment programs to conserve and improve rangelands.