Desertification has been a universal issue since it was discussed at UNCOD (United Nations Conference on Desertification) in 1977. The word desertification is defined here as land and vegetation degradation at various parts of the world including humid region as well as arid and semi-arid regions. This symposium aimed at examining the present situation of those areas suffered from desertification and studying out preventive measures of this phenomenon. The following subjects were set up: 1. Climatic variation and desertification. 2. Water use and salinization. 3. Agro-pastoral land use and degradation of land. 4. Natural environment and change in land use. 5. Preventives of desertification and suggestions for environmental management. Submitted studies are as follows: [Climatic variation and desertification] Tanaka, M. (Meteorological Research Institute): Recent climatic change and increased aridity in the tropical regions. Iwasaki, K. (Hokkaido University): Climatic fluctuations and desertification in Australia. [Water use and salinization] Matsumoto, S. (The University of Tokyo): Water utilization and salts accumulation with the agricultural development in arid lands. Takamura, H. (Rissho University): Desertification in Zambia and some problems of ground-water rising in Qatar. [Agro-pastoral land use and degradation of land] Takeuchi, K. (The University of Tokyo): Vegetation-ecological discussion on the ‘desertification’ phenomena in the southern part of semi-arid Australia. Tase, N. (University of Tsukuba): Background of desertification and environmental management in the U. S. A. Tamura, T. (Tohoku University): Development of pseudo-semiarid landscape in humid tropical Africa. Yasuda, Y. (University of Hiroshima): A study of the mechanism about the continual devastation of forest in Ege Sea region. [Natural environment and change in land use] Fujii, H. (Hyogo University of Teacher Education): On adaptation to the change of natural environment in case of modern agro-pastoral system and traditional agro-pastoral system in West Africa. Fujiwara, K. (University of Hiroshima) and Sadakata, N. (Hokkaido University of Education): Rural development schemes and changes in land use in the semi-arid region of South India. Yamamoto, S. (University of Tsukuba): Some observations on the traditional agricultural systems adapted to the physical environment of the semi-arid region in Northeast Brazil. Goto, A. (Kanagawa University): Traditional agriculture-system in arid and semi-arid area.-The case study of Iran-. [Preventives of desertification and suggestions] Kohno, M. (Kansai University): Desertification and its recovering policy in China. Kobori, I. (Mie University): Desertification and desertification control. Tomita, K. (Japan International Cooperation Agency): Preventives of desertification. [Discussion Opener] Ichikawa, M. (Akikusa Gakuen Junior College): On the present situations and problems of the desertification in the world. Presented subjects were discussed almost to the full. There are few studies, however, based on original data and regional comparison remains to be discussed.