On the edge of Alsatian towns, peri-urban territories as stakes in sustainable development. Sustainable development leads us to wonder about the urbanised areas around towns, where physical, ecological, social and economic transformations and different management methods remodel the land. This article deals with the case of Alsace. The specific regional traits are first studied, and then their different forms around Strasbourg, in the land of three frontiers and the region of Mulhouse are considered before examining the modalities of the cities from a distance. The perspective of “sustainable development” goes beyond a mere inventory of consuming space through housing and increased mobility, to take into account environmental issues, demographic and social mutations and the different modes of land governance and coherence posed by peri-urbanisation. Systemic approaches are still too fragmented and even deficient.