Developed out of necessity as a result of austerity economies and major cutbacks in public services, new coalitions between public, private, and economic forces now allow a multitude of unexpected synergies, and redefine participatory urbanism. The cooperative city offers scope for innovation and experimentation, with new forms of agency for decision-making processes: from peer-to-peer concepts, to crowd-sourced inner-city regeneration. How do such ad-hoc civic alliances outlast their activist roots, to transform urban governance?