The GIAHS project has the objective of documenting and fostering the viability and permanence of farming systems that are particularly remarquable due to the positive externalities that they generate and that benefit the environment and society at large. It will shed light on the positive roles that these systems perform and that do benefit not only the developing countries agriculture, but the global society as a whole, through the various environmental, social, economic and cultural services that they provide to their surrounding society. However, its primary purpose is to pave the way for ensuring a permanence of the existence of such systems. The policies that drive the transformation of agriculture and agricultural systems are many, and their interactions constitute a complex web in which the impacts of one or another policy are hard to individualize. The purpose of this paper is to share some lessons deriving from various approaches – mainly but not exclusively that of the RoA project – that could help realizing some rapid diagnostics of the major drivers of change that are acting on the farming systems targeted by the GIAHS project.