Hickman and Huaylla Sallo examine two London projects that reallocated street space, combining political-economic analysis with attention to the views of different actors. Their cases show that technical assessments of traffic and transport cannot alone explain whether a project becomes possible or how it is received. Design expertise, political priorities, business and resident perspectives, advocacy, conflict and the duration of consultation all shape implementation. Participation can lengthen a process while building support and improving delivery; it also reveals viewpoints concealed by an apparently apolitical appraisal. The article gives a practical account of knowledge transfer within planning: technical evidence informs deliberation, but does not replace it. Shared knowledge emerges through mediation among groups with unequal influence and competing expectations. The cases also make institutional capacity visible: staff time, funding and room for experimentation affect which proposals can be considered. A transferable planning lesson must travel with these conditions, rather than as a universal recipe.
