Drylands have always been the subject to intra- and inter-annul fluctuations of climate conditions, with important consequences for ecosystem function and productivity. Humans who depend on drylands for their livelihoods have coped with those fluctuations through such risk- averse responses as migration, extensive agricultural practices and collective tenure of land , water and other natural resources.These responses have evolved over thousands of years of intergenerational learning, which is why traditional knowledge holders are invaluable to discussions on development or restoration of sustainable land use systems. Today drylands are particularly prone to land degradation and desertificationdue in large part to practices that conflict with traditional knowledge, insecure land tenure and failing incentives or inadequate policies for sustainable land management.