This paper describes and critiques the approach and methods I used to research local knowledge of soils and land management in two ecologies and cultures of West Africa. The anthropological approach chosen, the iterative methods developed, and the differences in their effectiveness in the two cultures are discussed. Semi-structured interviewing of groups and individuals, including visual and participatory aids, observing and participating in agricultural operations throughout the year were central to my approach and methods. Differences in knowledge by age and gender were studied, and extension activities noted. Applications for extension from what I learned are provided to help fill a need for literature on methods for extension personnel to learn local knowledge. Local extension efforts at soil conservation show how learning and working with local knowledge would have improved those efforts. The training of both extension administrators and field-level practitioners, in learning and working with local knowledge are considered.