1.A paradigm shift is needed to make agriculture sustainable, and various substitutes for intensive agriculture have been proposed. However, moving from theory to practice, in the context of climate change, natural resource depletion and worldwide economic and social disorder requires a novel approach that goes beyond the confines of 'normal' scientific practice, to (a) consider ecological and socioeconomic processes within the agricultural socio-ecosystem and (b) involving stakeholders in the research process.2. We propose an innovative experimental approach for identifying management practices that optimize multiple objectives, deliver a portfolio of ecosystem services and satisfy the social demands of key stakeholders while improving the socio-economic welfare of farmers. Social-ecological experiments are undertaken in real-field conditions, involving stakeholders explicitly, all along the experimental pathway, to help untangle the drivers of social-ecological dynamics under various practices of land management and farming. As an example, we describe a socialecological experiment to reduce the intensity of weed control.3. These 'social-ecological experiments' go further, to participatory action research by not only involving stakeholders in the research process but also by manipulating simultaneously socioeconomic and ecological processes under real-field conditions to foster agroecological transition. Such experiments are distinct from adaptive management, participatory agricultural research and scenario-planning approaches as they highlight the interactions between ecological and social processes, manipulate the processes shaping the system and show causal links between patterns and processes. 4. Social-ecological experiments offer great opportunities for increasing stakeholders' acceptance of environmental policies or sustainable agriculture programmes implemented through adaptive management. These experiments may help to identify management practices that deliver a portfolio of ecosystem services and satisfy key stakeholders.
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