The economic orientation of agricultural production in Thailand during the past two or three decades through rapid conversion of forest land into farm land1,7,8) for the cultivation of cash crops such as cassava, sugarcane, etc. has resulted in severe soil erosion, land degradation and decrease of the soil moisture content due to the lack of implementation of appropriate soil and water conservation measures. Under these circumstances, the authorities concerned in Thailand have addressed the above-mentioned problems in terms of effective use of land resources and environmental conservation. In this paper, (1) soil and water conservation measures for upland areas that have been implemented on the project promoted by the authorities concerned in Thailand and (2) the results of the study on evaporation control of farm pond that was carried out from January 1994 to May 1994 in East Thailand were reported.