This paper presents results of a case study of the SANREM's research project and two other UAF case studies in the Central Highland of Vietnam. These studies used similar participatory research approach to generate empirical evidences to patterns of land use change as these are influenced by multidimensional factors. Environmental consequences associated with these land changes were also reported. The paper shows that changes in economic policies, institutions and market access led to a large transformation of forestland into agriculture. The rapid expansion and intensification of agricultural production, driven in part by expanding population, places high pressure on the natural resource base and causes high negative externalities in the uplands, particularly in marginal lands. In all case studies, rates of degradation of forests, soils, and water remain high and threaten agricultural sustainability. Recently, national and local government took some efforts to overcome negative environmental consequences of agricultural development in the uplands, but their impacts are still limited. Balancing agricultural development and environmental protection is currently a major challenge for upland development. For meeting this challenge, the paper emphasizes the need for setting enabling policies and institutional framework that better promote sustainable agriculture and natural resource management practices in the uplands.