West Africa has major problems relating to the impact of slash-and-burn shifting cultivation on soil systems. In order to design more sustainable yam cropping systems, agronomy research in Benin has implemented trials in partnership with smallholders on alternative yam-based systems using shrubby (Gliricidia sepium) and herbaceous (Aeschynomene histrix) legumes. In the first phase, farmers modified these new systems within their own constraints; the systems were then further evaluated. The agronomic and economic performance of farmer-adapted alternative yam-based cropping systems and the implications for wider international application are discussed. (Résumé d'auteur)