Modern agriculture has led to a simplification of maize-based cropping systems and the extensive practice of monoculture maize (MM). This has led to problems such as yield reduction and soil quality degradation. Meanwhile, the overuse of inorganic fertilizer to increase yields comes with a high environmental cost. Maize grown in rotation with grain or forage legume crops often yields more and requires less application of synthetic chemicals (e.g. fertilizers, pesticides and herbicides) than continuous MM. Thus, maize–legume rotations in tandem with the application of farmyard or dairy manure or other organic wastes is deemed an environmental-friendly strategy for sustainable agriculture development, and can help the agri-food production sector to produce affordable and healthy foods for consumers, reduce air and water pollution and build-up healthy soil for the farmers of tomorrow. This chapter summarizes the recent literature on the agronomic, economic, ecological and environmental assessments of maize–legume crop rotation systems.