Bringing together cutting-edge studies into a range of contemporary sites of urban concern, this volume unfolds the collective research agenda of urban cosmopolitics in three directions: the relational constitution and political effects of urban technologies, infrastructures, and other material-semiotic agencies (agencements), the coming together of new urban concerns, constituencies, and publics (assemblies), and the coalescing of urban practices into shared spaces of co-existence, life-support, and survival (atmospheres). Together, we assert, this exploration of urban cosmopolitics amounts to a `strong program¿ of urban studies, allowing us to shed new light on key topics of contemporary research, including urban planning and citizen publics, economic dynamics and constraints, street life and the everyday, built environment dynamics and differentiations, and disasters, risks, and sustainable transitions.