Livable Cities - London AMPS | City, University of London Page 91 Co-creation challenges included data availability, tool complexity, and the need for continuous stakeholder engagement and capacity building. Addressing these were crucial for success. Qualitative insights highlighted these challenges and suggested strategies for overcoming them, such as engaging departments through one-on-one meetings like Riga did. Co-creation was seen as beneficial for fostering innovation and social learning. Stakeholders could freely express the reasons for their positions, which was enlightening for decision-makers. Stakeholders and city administrations learned from each other, leading to more ambitious policies,31 confirming that participatory modelling generates socially robust knowledge by fostering continued learning.32 Data collection effectiveness varied. Cities like Setúbal faced challenges in obtaining behavioural data, while others like Mantova did not collect citizen data. This is even though each stakeholder holds specific expertise and knowledge which they could contribute to the process.33 Innovative approaches included using existing energy matrices and stakeholder surveys. The co-creation process evoked new ideas for measures like an energy poverty fund and the promotion of an innovation cluster in local industries. Our research suggests that the production of new knowledge, skills, and resources due to the engagement of different perspectives remains a key point in the co-creation processes.34 Most cities reported fair discussions with equal stakeholders' opportunities. In Mantova, discussions were collaborative and constructive. In Dijon, some participants found it difficult to express their views due to the lack of quantitative sectoral data, but overall, the discussions were fruitful. The process enhanced the quality of measures and stakeholder responsibility for implementation. For example, Setúbal integrated co- creation into its local CAP, while other cities are in the process. The increased ownership and involvement that co-creation can achieve is one of its main benefits,35 as it makes the attainment of longer-term visions possible.36 Favourable conditions included transparent communication and high-level stakeholder involvement, while obstacles included data collection difficulties. Recommendations for future co-creation processes include involving diverse stakeholders from inception, maintaining transparent communication, implementing feedback mechanisms, and considering all perspectives. Stakeholder surveys found the EU City Calculator useful for developing climate policies, appreciating its real-time simulations and scenario visualisations, despite needing more detailed data and complexity for non-technical users. Overall, the co-creation process effectively engaged stakeholders, fostered innovation, and supported climate action plan development with locally tailored measures. While challenges existed, the overall impact was positive. Insights will refine methodologies and enhance stakeholder engagement in future efforts. The process significantly contributed to developing CAPs, involving stakeholders in scenario and measure development, leading to context-specific policies with broad support. The tool´s maturity at the development stages of the project limited outreach, however, simulations and co-creation helped stakeholders understand decision impacts, leading to informed policymaking. The process is valued in itself, aligning with trends in public policy and urban planning.37 Collaborative approaches enable citizens to develop city ownership, empowering them and contributing to successful urban policies.38 Co-creation is crucial for local climate action development and implementation, generating a new culture in planning, opening communication channels, and enabling transformative changes for climate neutrality. However, its success depends on cities' financial, structural, and cultural contexts. The co-creation process sparked discussions on integrating new measures tailored to cities' needs, with four measures integrated into the tool. Inclusion was based on data availability, indicators, literature support, timescale, city scale, and tool linkage. While many measures were considered, only a few, particularly in energy and reforestation, were added to the tool, within the project´s timeframe. The process highlighted the need for broader sectoral involvement beyond industry. Findings emphasise that while modelling tools are valuable, they have limitations. Urban spaces vary based on economic, cultural, and climatic factors,
