Current landscape mosaic patterns of land cover in Northern Thail and can be seen as resulting from adaptation of traditional agricultural sy stems over time. During the 1950’s, little influence from the lowlands had been imposed on traditional systems in higher elevation zones. Subse quent outside influences, such as markets for new crops associated with both opium crop replacement programs and expansion of lowland agro-industry, led to extensive clearance of forest in mountainous areas. Increasing clearing size changed land use patterns from those formerly based on small clearings, with substantial impact on forest rege neration and watersheds in general. Land use constraints imposed by the Royal Thai Government (RTG) on highland area s, such as establishment of national parks, wildlife sanctuaries, and a watershed classificati on system, combined with political tensi ons, national security issues in border areas, and foreign pressure to stop opium production, to further influence the dir ections of agricultural development. As part of these processes, a series of crop substituti on-oriented projects were im plemented during the 1980’s, linked with efforts by the RTG to improve health service, education, infrastructure, and market access in the highlands. Population growth and in-migration furt her increased land use pressure, and by the late 1980’s projects like CARE Thailand and the Sam Mun Highland Devel opment Project (SMHDP) began devel oping an integrated approach that included participatory land us e planning (PLP) to address the multitude of problems, and d evelop strategies and solutions in partnership with highland co mmunities. These efforts further affect ed agricultural systems in transition. During the 1990’s, concern with envir onmental issues grew rapidly. In itial concern focused on criticism of dam projects and state management of forest lands, leading to proposals for a community forestry law that would allow local participation in management of forest resources. But growing environmental awareness in lowland and urban populations was also associated with realization of the importance of upper watershed forests in the northern region for their future livelihoods. While a regular supply of clean water had long been taken for granted, now it was now becoming an issue of concern. This set the stage for growing debate and tension among upstream and downstream interests, which has intensified with recent flash flood and landslide disasters. Meanwhile, governance reform efforts led to a new national constitution and stre ngthening of local governance institutions. Additional projects initiated by the Royal Family, the RTG and various N GO’s to work closely with highland villagers have been responding to the challenges presented by these developments. As a result, locally-negotiated land use planning, combined with new tools, ranging from methods for local monitoring of watershed services to GIS and remote sensing technology, are coming together in a prom ising approach for addressing both local and societal needs. ICRAF Chiang Mai, working with the Ro yal Forest Department, Chiang Mai Un iversity, the Queen Sirikit Forest Development Project, Care-Thailand, and ot her partners, are conducting research on these issues and processes at their benchmark research site in the Mae Chaem district of Chiang Mai province in northern Thailand. The focus of this research is on d evelopment and pilot testing of a comprehe nsive spatial inform ation system to support participatory management of natural resources in upper tributary areas where national conservation concerns seek to constrain local land use practices. The system has four major components: 1. Negotiation and articulation of local land use plans and agreements that incorporate local needs, as well as concerns of downstream comm unities and national society. 2. Spatial information tools that provide: a) a basis for formal recognition of local land use agreements; b) transparency and accountability in mon itoring compliance; c) additional information that will enhance the capacity of local institutions to manage land use in a manner that can improve local livelihoods while sustaining environmental services. 3. Continuous monitoring and assessment of watershed se rvices by local watershed management networks. 4. Analytical modeling to provide assistance for both local managers and the general public in interpreting information related to natural resource management issues. Field-testing of the overall system includes additional detailed information on land use history, local land use patterns, and other factors that will assist in assessing the effectiveness of the system and its various components. Initial pilot implem entation of these efforts began in 2001 in four sub-watersheds of Mae Chaem, which were selected to represent a range of cu rrent land use conditions found in upper tr ibutary watershed areas. This paper reports on progress of these effortss, including evolution of land use patterns and local response to the tools and approach. It also discusses plans for further expansi on of pilot tests, and potential for wider application and adaptation in the region.