Drawing on the Mukuru Special Planning Area in Nairobi (Kenya), this article analyses enabling conditions for scaling participatory planning in otherwise exclusionary urban political environments. It contributes to debates that focus on qualitative changes required to enhance citizen participation and on the integration of low-income residents’ needs, demands and innovations into city-wide planning practices around informal settlement upgrading. The article identifies three conditions that are key to enable and enhance the success of scaling efforts. First, moving to scale requires identifying, generating and making strategic use of political opportunities and building political momentum around them. Second, in addition to mobilizing, organizing and connecting stakeholders at different levels, successful scaling efforts must also promote qualitative changes in the way these stakeholders see themselves, and how they interact with and relate to each other. Third, going to scale requires the capacity to manage conflict successfully and prevent attempts to disrupt, co-opt or halt a scaling process.