Marvin, McFarlane and Rutherford’s article argues that contemporary urban infrastructure can no longer be understood only as roads, pipes, cables or networked systems of provision; instead, infrastructure is being extended into the domains of atmosphere, care, ecology, digital computation and cognition. The authors identify five forms of infrastructural extension: elemental infrastructures, which govern air, water, temperature and chemical flows; infrastructures of care, which include affective, informal and relational practices of sustaining life; multispecies infrastructures, which recognise the role of animals, plants, fungi and microbes in shaping urban systems; cybersymbiotic infrastructures, where algorithmic, robotic and sensor-based systems reorganise urban operations; and neurotechnical infrastructures, where cognition, affect and neural data become integrated into urban governance. The central claim is that infrastructure is shifting from a system of service provision to a mode of modulation, shaping not only flows and resources but also sensation, survival, emotion, species relations and human interiority. The article is especially important because it warns that these new infrastructural forms may intensify inequality through opaque systems of optimisation, surveillance and selective exposure. At the same time, the authors do not treat infrastructural extensions as simply oppressive; they are ambivalent terrains of experimentation, care, contestation and control. Ultimately, the article calls for an expanded, interdisciplinary and ethically alert urban infrastructure studies capable of analysing how life itself is increasingly captured, organised and stratified through infrastructure under conditions of planetary crisis.