Data Power in Action: Urban Data Politics in Times of Crisis develops a profound reconceptualisation of contemporary urbanism by arguing that data has become the primary infrastructural medium through which cities are governed, populations classified and crises administered in the twenty-first century. Rather than treating data as a neutral technical resource, the volume conceptualises urban data power as a historically contingent and politically charged regime emerging from the convergence of platform capitalism, algorithmic governance and digital infrastructures. Ola Söderström and Ayona Datta demonstrate that contemporary cities are increasingly organised through processes of datafication, wherein everyday activities, mobilities, emotions and social interactions are transformed into quantifiable streams capable of extraction, monetisation and governmental intervention. Particularly significant is the book’s insistence that data politics cannot be understood solely through the experiences of the Global North; instead, fragmented infrastructures, informational inequalities and asymmetrical digital transitions in cities such as Nairobi, Cape Town, Varanasi and Hangzhou reveal the profoundly uneven geographies of algorithmic urbanism. The volume critiques the ideology of seamless computational governance by exposing how crises—including pandemics, urban precarity, climate emergencies and infrastructural breakdowns—operate as legitimising mechanisms for intensified surveillance and expanded technocratic control. Equally illuminating is the notion of “data power in action”, which redirects attention from abstract infrastructures toward situated practices, tactical resistances and everyday negotiations through which citizens, workers, activists and institutions interact with digital systems. Case studies concerning Indian COVID-19 war rooms, Chinese Social Credit infrastructures, South African data activism and Nairobi’s platform labour economy collectively demonstrate that urban data governance functions simultaneously as an apparatus of extraction and as a contested terrain of political struggle. The book’s most important intellectual contribution lies in revealing that algorithmic urbanism is neither technologically inevitable nor universally coherent; rather, it is constituted through unstable relations between states, corporations, infrastructures and lived urban experiences. Ultimately, the volume advances a critical urban theory of data in which the future of democratic citizenship depends upon resisting the reduction of human life to calculable informational patterns and reclaiming the political dimensions of visibility, participation and collective urban rights within increasingly automated societies.