A research project on improved fallows examined how short-term rotations of selected perennial tree and shrub species impact cereal yields and soil quality in subsistence maize cropping systems. The effects of improved fallows on maize yields were significant when combining a tree species (Gliricidia) and a nitrogen-fixing legume (Stylosanthes). The results suggest that this innovative agroforestry strategy holds significant promise for enhancing soil fertility, maize yields and food security throughout Mali and sub-Saharan Africa.