In 1987 UNEP stated that 27 million hectares of productive land were being desertification each year, at which rate not one hectare of productive land remain on earth in 200 years time.

Despite being widely perceived as environmental issue of major importance, desertification has been subject considerable confusion, misinterpretation and lack of clarity regarding its teristics and occurrence.

This paper examines recent scientific developments enhance understanding of desertification processes but raise doubts about previous assessments of the problem. In particular, natural fluctuations in dryland vegetation communities caused by inherent environmental instability need distinguished from degradation of the soil system caused by human activities.

Improved satellite-based monitoring of environmental changes in Africa, and recent global assessment of human-induced land degradation by ISRIC/suggest previous assessments ofdesertification may have over-estimated the worldwide extent of the phenomenon by a factor