The International Society of Urban Planners conference (ISOCARP) took place in parallel in different Dutch cities, following a theme proposed by each of the participating municipalities. In Eindhoven (known for its connections to the multinational Philips), the issue of the night landscape was put forward as a collective project requiring attention. The aim was to collect new participatory design scenarios halfway between traditional top-down planning and novel bottom-up strategies. Before describing the results of the atNight project, this article examines a series of participation processes carried out in Barcelona, which served as the starting point for building a new working method.