This article analyses the extent to which the concepts underlying land policies in West Africa that prevail amongst the development organisations most active in this field correspond to the results of the intense debate on the same subject over the last three decades, which has involved almost all branches of the social sciences: ethnology, legal anthropology, sociology, history and rural economics. It is found that the outcomes of these academic analyses are in sharp contrast to the approaches propagated and translated into practice by development agencies, which often start from oversimplified and inadmissibly generalised assumptions, so that one must ask whether the diverging logics of these two disciplines are responsible for this marked difference.