Galán-Cano et al. reposition urban metabolism as a contemporary framework for reading cities through the coupled movement of energy, materials, waste and institutional decisions. Their iconic proposition is the transition from linear to circular metabolism: urban sustainability depends not simply on reducing inputs but on reorganising resource cycles so that waste, energy and material stocks become part of a regenerative system. Methodologically, the review combines bibliometric analysis with a historical and conceptual survey of metabolism, circular economy, energy transition and SDG-oriented planning. Its most important diagnostic is epistemic rather than merely technical: comparison between cities remains weak because metabolic data are inconsistent, inaccessible and insufficiently standardised. The paper therefore turns data architecture into a condition of environmental action. Its wider contribution lies at the intersection of industrial ecology, urban planning and systems theory, where the city is treated neither as an organism by metaphor alone nor as a statistical container, but as a measurable and transformable configuration of resource relations.
URBANISM MEETS ART