Debord’s “Theory of the Dérive” formulates drifting as a method for reading the affective and political contours of urban space. Its iconic idea is that the city contains psychogeographical currents, fixed points and zones of attraction or repulsion that exceed administrative geography and functional planning. The theoretical contribution is to transform walking from leisure or transit into an experimental procedure for detecting the emotional structure of urban terrain. Methodologically, the dérive combines letting-go with calculation: the subject suspends habitual motives for movement while attending to the patterned force of ambiances, microclimates, neighbourhood images and social morphology. Its conceptual operation is psychogeographical exposure: the city is disclosed as a field of attractions, barriers and affective gradients. The bridge to the wider field connects avant-garde art, critical urbanism, geography, performance and spatial ethnography, making movement itself a tool for diagnosing the forces that organise everyday urban experience.