This article examines Piazze Aperte—the tactical urbanism programme promoted by the Municipality of Milan—as a policy device that reconfigures how streets can be reclaimed, governed, and collectively used. Drawing on three strands of urban theory—tactical urbanism, temporary uses, and collaborative approaches—the analysis adopts an embedded research perspective to investigate both spatial outcomes and institutional effects. Rather than treating temporary street redesigns as provisional experiments, Piazze Aperte has employed low‐cost and reversible interventions to accelerate implementation, stimulate civic initiative, and establish new forms of cooperation between residents, schools, associations, and municipal offices. The programme has contributed to redefining streets as public social infrastructures, linking spatial transformation with shared stewardship and administrative adaptation. The case of Piazzale Bacone—one of its implementations—shows how tactical measures can generate everyday appropriation, conviviality, and visible change within a short timeframe while also revealing material fragilities, quality weaknesses, maintenance challenges, and uneven territorial coverage. These tensions expose the strategic ambiguity of temporary interventions when long‐term consolidation is not ensured. The article argues that Piazze Aperte provides substantive evidence for ongoing debates on the institutionalisation of experimental planning practices and on the governance of public space as a negotiated commons. From a policy perspective, the programme illustrates the transformative potential of temporary uses and civic collaboration in reshaping urban spaces, supporting liveability, and reforming institutional practice while simultaneously highlighting two key challenges for future development: ensuring the durability of interventions over time and extending their reach to less organised yet equally disadvantaged urban areas.
Antonella Bruzzese (2026) studied this question.