Summary Tropical tree plantations provide indispensable renewable goods to the global market and family farms represent the majority of their surface area and production. To ensure the sustainability of plantation systems, environmental and socio-economic conditions should remain favorable during several decades. How can such conditions be ensured when the environment is changing? Even if the local consequences of global increase in temperature are difficult to assess, the farmers will probably face a more variable climate, with probable changes in rain patterns. Moreover, all natural resources have recently faced hugely variable prices related to variations in global demand. High prices attract new investors and drive the extension of plantations into new areas, inducing land-use changes and changes in farming structures. The final aim of the project is to analyze how smallholder’s tree plantations can adapt and keep sustainable whereas they face variable climatic conditions and deep changes in their socio-economic context. Do farmers perceive these risks and do they initiate adaptive strategies? Rubber tree-based systems in Thailand will be used as a model of tropical family plantations integrated in a major global commodity channel. The project will assess both the specificities of rubber cropping and the more general features of tree plantations. The originality of the project relies on the multi-disciplinary approach of both the characterization of changes and their consequences on rubber plantations and the related risks for farmers. Plant and soil sciences will be associated to social sciences and economics. We will analyze the way socio-economic factors interact with biophysical factors to determine farmers’ vulnerability or adaptability to changes. This will require the identification of relevant indicators to measure farmers’ adaptation, and the impacts of changes on sustainability and resilience of the systems. We will refer to the Sustainable Livelihood Framework (Ellis, 2000) to represent the household/holding , combined with the OECD risk matrix (2009) to assess households’ viability. We will focus on two major factors, (i) the type of holdings, particularly the emergence of new investors and (ii) the share-cropping contracts that frame the management of plantations. The main biophysical risk relate to climate changes and to the extension of plantations in new and more adverse areas. We will evaluate the risks at plot or farm levels, as well as potential externalities, in terms of soil sustainability (soil fertility preservation related to soil physical quality and soil functional diversity) and tree adaptation to water stress. Specific ecological constraints linked to the different cultivation area will be considered. In the North-eastern rubber extension area, the climate is drier and the soil fertility is low, whereas in the traditional area (South) continuous rubber cropping occurs for more than 50 years (third cycle). In the North, the specific issue of rubber installation in mountainous area will particularly focus on the effects of terracing, considering the impact on water flow and water balance. A typology of rubber farming systems and of practices will be proposed from socio-economic survey, particularly regarding land management and latex harvesting systems. The impact of practices on economic performances, soil physical and bio-functioning will be evaluated through specific indicators that will be developed or adapted in the perspective of multi-criteria evaluation of plantation systems. The information will be integrated at different scales from plot to farm and watershed and shared with stakeholder through a co-innovation platform. Beside the specific case of rubber plantations, a more generic output of the project is to determine, through modelling and risk framework analysis, the most significant indicators to be observed to assess the long-term adaptation and sustainability of tree-based family farms.