This paper analyses planning responses to middle-income informalities in Nairobi city, an increasingly significant element of informal urban development focusing on ad hoc zoning practices and regularisation. The findings highlight aspects of fractured governance, negotiated planning, and power struggles involving middle-income housing developers and other actors that exacerbate housing informalities rather than ameliorate them. The article reveals how different rationalities drive the different spheres of government functionaries, some of whom use planning systems for financial and political gain. Building on debates around ‘conflicting rationalities’ in planning, the paper proposes the concept of ‘entangled rationalities,’ which has scope to highlight the nuanced, multi-actor and non-binary nature of interactions between planning, political and development practice characterising responses to middle-income informalities in the global south cities and how this shapes urban outcomes.