This chapter advances the ‘hack’ as a conceptual, empirical and methodological object for thinking through disrupting the urban and seeding change. The hack operates below the level of formal urban planning and architectural interventions and yet comes with the capacity to disrupt both and to seed change. While the hack is present existing literature on the digital and informality, the hack is emerging a distinctive concept and is being used systematically in new domains. But more than just a conceptual tool, the hack is also an object and a method for working towards alternative possible cities. The hack’s power for disrupting and seeding different urban outcomes is, I suggest, in its chameleon-like nature and its ability to prefigure change.