This article examines the origins and evolution of the terroir approach as an organizing idea in development planning in West Africa. We consider the evolving meaning of the terroir concept in three distinct periods: as a research approach crafted in a French geographical school; as a site for research-development programmes, and, most recently, as a tool for conservation planning, territorial restructuring, and land privatization. An important shift in the meaning of the terroir concept is apparent in its evolving uses. For the terroir school, the terroir came to represent the socio-natural heritage of a group in which its social organization and pattern of resource use became inscribed in the landscape. The concept took on new meaning in the late-1980s as an appropriate location for on-farm research by agricultural development planners. The terroir became both an alternative research site and a setting for mobilizing rural populations to adopt new land management and farming techniques. The meaning of the concept shifted again in the 1990s with the advent of the gestion des terroirs approach. In the hands of conservation and development planners, the terroir was conceived of as a scale of intervention for a host of government, aid donor, and NGO programmes. In summary, a significant change in the meaning of the concept has taken place from one in which the notion of local heritage was dominant to one that emphasizes territory and boundary clarification.