Livable Cities - London AMPS | City, University of London Page 86 the city's objectives. By analysing these processes, the study provides insights for cities, policymakers, and stakeholders in urban climate action planning, highlighting challenges, best practices, and lessons to promote collaborative sustainable development. Local stakeholders' contributions are essential in designing effective climate strategies, central to co-creation in decarbonisation pathways.7 This research addresses (i) how co-creation processes, facilitated by the EU City Calculator, contribute to Climate Action Plans (CAP) development and (ii) what lessons are learned from these processes in the pilot cities. The article introduces the role of co-creation in transformation pathways development through modelling tools, outlines a mixed- method and transdisciplinary research approach, presents results, and concludes with recommendations for further research including implementation issues of CAPs. To explore further details about the EU City Calculator, please refer to the supplementary materials provided with this research or visit the project webpage.8 Co-creation in climate policy development The co-creation concept,9 often synonymously used with co-production, involves active engagement, participation and collaboration between state agencies and citizens, extending beyond consultation to add valuable insights to outcomes.10 This concept has gained traction in urban planning, policy development, and environmental modelling, which is characterized by multidimensional processes involving knowledge transfer, production, and use.11 Addressing urban challenges requires cross-sector collaboration and the inclusion of various actors in public policy, enabling joint decision-making.12 Participation in co-creation platforms can enhance the legitimacy of decisions and innovation in implementing solutions in cities.13 In climate policy, co-creation engages local actors in decision- making for decarbonisation strategies, crucial for transformative processes toward climate-neutral pathways.14 This collaborative development of policies, solutions, or initiatives involves various stakeholders, including government entities, the private sector, civil society organisations, and citizens, leading to inclusive, context-specific outcomes with greater buy-in. In climate action planning, co- creation integrates local knowledge, resulting in more effective, sustainable, and adapted solutions.15 The theoretical foundation of co-creation is rooted in participatory governance, stakeholder engagement, and collaborative decision-making, recognizing that complex challenges like climate change require a holistic approach leveraging diverse experiences, resources, and insights.16 By fostering co-creation, policymakers and urban planners can ensure that strategies and plans align with local needs and priorities, making co-creation a fundamental characteristic of social innovation for urban climate policy while empowering local communities.17 Co-creation processes are significantly shaped by social, cultural, and political factors, introducing complex challenges related to governance dynamics and power distribution among stakeholders.18 While co-creation has the potential to dismantle hierarchies and existing power structures, a critical consideration is the selection and inclusion of participants.19 The availability and distribution of resources can substantially influence both the process and its representativeness. It is crucial to clearly define and communicate the role of the co-creation process in policymaking from the outset and ensure its realization by the conclusion.20 Modelling tools can support co-creation by enabling the formulation of pathways, action plans, and policies. These models facilitate decision-making by incorporating diverse perspectives in collaborative processes, providing scientific insights and exploring scenarios, trade-offs, and interdependencies. They thereby enable cross-sector collaboration and knowledge integration which are prerequisites for transformative changes.21 However, models require social validation, reflection on concepts and values, and commitment to capacity building. This fosters stakeholder engagement and learnings to generate new scientific and socially robust knowledge.22
