Research presented here was financed by the National Research Agency (ANR) between 2005 and 2007. It brought together sociologists, architects and town planners around the question of the prerequisites for city-dwellers to decide to walk in town? Four districts, two in Grenoble (France) and two in Geneva (Switzerland), served as a basis for field work in three phases: surveys combining an architectural and sensory approach to the terrain; interviews with users; and ethnographic observations of walking practice. The results of the research throw doubt on the spatialist approach, still influential in architecture, which maintains that space determines usage. The findings suggest the need for a reappraisal of the power exerted by atmosphere over walking and urban practices. Atmosphere, by influencing both registers of walking (doing and experiencing), demonstrably contributes to the walkability of a place, just as much as its design does.