The Camargue, South of France, is an agricultural region highly multifunctional and with strong issues linking the environment and the society. Evaluating scenarios of alternative agricultural systems extension in this region imply to use tools that allow Prospective, Integrated, Multiscale and Participatory Assessment of Agricultural Systems (PIMPAAS). In this paper, we reviewed the use of three approaches (BEM, ABM and LUCC) for PIMPAAS. After a presentation of the three approaches, we analyzed their advantages and drawbacks, and possible complementarities. As it is not possible to implement the three approaches together at one time, our aim was to make a choice for the Camargue. We found LUCC to be the least suitable approach, mainly because it does not allow participatory processes at farm scale. BEM and MAS appeared to be the most suitable tools as they allow quantitative and ex-ante studies and are able to incorporate the three sustainability domains. Their ways of up-scaling are complementary: BEM seems efficient for up-scaling from field to farm and field to region, whereas MAS allow up-scaling without aggregation from farm to region. We believe that the combination of the two approaches will enable highly participatory evaluations of alternative farming systems. Using the results of this analysis, we recommend using a combination of MAS and BEM in a global framework. We are currently implementing a framework in the Camargue to test this combination and to evaluate its suitability for prospective, multiscale, multicriteria and participatory evaluation.