different combination that determines the diffusion of deserti- cation in the territories, attributable mostly to climatic changes and the activities of the man, makes our job challenging and complicated, since it varies from region to region. We are aware of all this and therefore we think that the methodological approach of survey of the data is an extremely important element to locate of the phenomenon and to monitor its course. This work, which is characterized for its multi-disciplinary approach, suggests solutions that we wish will quickly find concrete applications at international level. Prof. Bruno Dettori President CNLSD (Comitato Nazionale per la Lotta alla Siccità e alla Desertificazione) v