Stephen Graham and Simon Marvin’s Splintering Urbanism: Networked Infrastructures, Tech- nological Mobilities and the Urban Condition (2001) brought the study of infrastructure to the core of urban studies and inspired the “infrastructural turn” in the social sciences more widely. The book catalyzed a rich trove of research on how technology and society are impli- cated in the production of contemporary cities. More than any other publication, it has ani- mated the socio-technical systems of water, energy, transport, and telecommunications as fundamental to the functioning and livability of cities. It has inspired scholars to seek out the vital processes and politics of the cables, wires, pipes, and roads that undergird urban development. The twentieth anniversary of the book provides a good opportunity to re!ect on the impacts of the book and to consider the emerging trajectories of scholarship on urban infrastructure.