Stephen J. Collier is Professor of City and Regional Planning at the University of California, Berkeley. He studies city planning and urban governance from the broad perspective of the critical social science of expertise and expert systems. His work is engaged with science and technology studies, actor-network theory, governmentality studies, and pragmatist approaches to infrastructure and finance. Collier is author of Post-Soviet Social: Neoliberalism, Social Modernity, and Biopolitics (2011)—a study of urban planning and post-socialist transformation in Russia—and, with Andrew Lakoff, of The Government of Emergency: Vital Systems, Expertise, and the Politics of Security (2021)—a genealogy of the American emergency state. His current research relates to urban climate adaptation in various contexts, and engages theoretical debates around resilience, crisis government, and the politics of expertise.