Abstract Transitioning towards a circular built environment and turning waste into resources have become one of the new sustainability paradigms today. However, a circular transition can be considered a ‘wicked problem’. The multiple dimensions and scales of the circular transition and its substantial spatial implications fit well into the planning approach of Geodesign. The Horizon 2020 funded project “Resource Management in the periurban Areas - Going beyond Urban Metabolism (REPAiR)” implemented an innovative Geodesign approach. Moreover, it explored its capability to support spatial decision-making processes for the circular economy transition of the built environment within urban planning practices. This article aims to understand to what extent a process of Geodesign, which is conducted with the support of a digital tool and a Living Lab approach, can support the creation of localised circular economy strategies and foster the circular economy transition in cities and territories. The analysis explores and compares the results of three European cases -Amsterdam, Hamburg and Naples. It considers the kind of data input required to run the process in every phase, the stakeholders involved and their typology, the specific urban or territorial, planning and governance scales of analysis, and the final output definition after the Geodesign process implementation. The approach outputs constitute a decision support system for easing negotiations between local actors regarding the circularity strategies to implement. The findings reveal an intertwinement between different forms of knowledge included in the process, ranging from sustainability to governance and design, and the actors engaged in planning a circularity transition spatially. However, even using similar starting data, the local information and the starting conditions strongly influence the process and the types of strategies elaborated in each case.

Highlights • Geodesign is an approach that combines different kinds of information and introduces waste flows as spatialised data and metabolic processes as essential components in identifying transformative actions and assessing the relative impacts. • A transition towards circular cities and regions needs to include diverse urban stakeholders and their knowledge at the discussion table, integrating deliberative processes in spatial planning and combining complex data with soft data. • In a circular transition, data should represented through different cartographic representations and visualisation. Like synthetic, visual instruments, maps and diagrams allow different stakeholders to negotiate and modify existing policies and governance, identify new policy and governance developments and even define spatial and environmental design proposals. • Geodesign relates different actors, waste flows, policy and governance factors influencing the innovation process in the built environment • Systems thinking is here revealed to be at the core of the design of the proposed Geodesing method. • Geodesing approach to treat material flows as spatial phenomena as the starting point for more resource-efficient spatial planning rather than approaching the transition to a circular economy from a numbers-driven perspective.