For decades, urban planners have been searching for ways to meaningfully involve constituents in the planning process. While advances have been made in considering the public’s opinion when making decisions about development, there remain obstacles to participation such as constraints on time and resources, and people’s lack of confidence that their contributions will influence outcomes. At present, new digital technologies such as the Internet, GIS (geographic information systems), and mobile phones promise new opportunities for citizens to be involved in urban design, planning and development decisions. Likewise, new development projects such as the Zaragoza Digital Mile in Spain are also integrating digital media technologies into the public realm of the city. In considering the potential synergies between new technologies and digitally enabled public spaces, this paper asks, how can digital technologies harness people’s distributed knowledge and energy to more directly shape their urban environments?