Climate action in cities is increasingly recognized as of strategic importance to accomplish the global governance of climate change. In Europe, cities are adopting a “mission approach” to accelerate urban transformations and reach climate neutrality targets by 2030. While the “Mission” unfolds, it is worth acknowledging that in the last decade, cities in Europe have engaged in climate action. Through a selection of empirical case studies, this review examines the main governance approaches that have been used to analyze the implementation of transformative adaptation and mitigation measures in the Global North. This approach aims to respond to the gap between policy rhetoric of urban transformations and the realities of on-the-ground implementation. This systematic literature review asks the following question: what are the challenges and key success factors amongst the governance approaches that have informed the implementation of transformative climate agendas in cities of the Global North? The findings cover conceptual approaches to analyze the governance of urban transformations, and cases illustrate the challenges in mainstreaming climate action, even in cities that are environmental champions. The need to strengthen collaborations to deliver transformative interventions is raised, while the authors also caution about power imbalances in network governance.

This thesis has been supported by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 945139, a COFUND program with Fundación Tatiana Pérez de Guzmán el Bueno. The decarbonization of urban environments understood as the reduction of greenhouse gas (GHG) emissions in citieshinges critically on accelerating household energy retrofits, particularly across the European Unions aging and energy inefficient housing stock (Buildings Performance Institute Europe, 2024; UNEP, 2024). Despite increased public subsidies following the launch of the EU Green Deal (2019), and the resulting multi-level policy alignment aimed at achieving climate neutrality by 2050, household energy retrofit rates remain persistently low across EU citiesparticularly in Spain, where renovation efforts continue to fall significantly short of EU targets. This implementation gap motivates our study, which examines the implementation of household energy retrofit policies in Madrid as a lens to explore the broader challenges of urban transformation processes toward sustainability. Through a mixed-methods approach, this research combines quantitative data to map the socio-spatial distribution of household energy retrofit subsidies at both district and neighbourhood levels, with qualitative analysis to examine the role of actor-intermediaries in bridging municipal objectives and household decision-making in the context of energy retrofits. Building on the framework by Martiskainen and Kivimaa (2017), we propose a categorization of intermediaries into place-based and non-place-based types, adding a spatial dimension to better understand their roles within the retrofit system., and illustrate this categorization in our case study in Madrid. By integrating theories of urban transformation and transition intermediaries in the context of zero-carbon buildings, the study aims to advance a spatially grounded approach to better understand how policy materialize across heterogeneous urban environments. Results indicate that subsidy uptake is disproportionately concentrated in three socioeconomically vulnerable neighbourhoods characterized by deteriorated building conditions. Although these areas were not being explicitly prioritized in the design of subsidy programs, the findings suggest that material necessity and the needs for repairsrather than environmental concerns are important drivers for demand of energy retrofits at the local level. Furthermore, the study underscores the importance of local network formation and demonstrates how organized community leadershipsuch as that in the neighbourhood of Orcasitascan play a critical role in catalyzing collective retrofit adoption at the local level. Theoretically, this research contributes to urban transformation scholarship by offering a granular, spatially grounded analysis of how climate policies can advance in specific areaspatterns of transformation that are not visible through an analytical lens focused solely at the municipal level. Furthermore, a greater integration of place-based and non-place-based intermediary activities could enhance the feedback loop between neighbourhood-level dynamics and data-driven insights generated at broader governance levels. Policy recommendations emphasize the need for targeted strategies, facilitating local network formation, and building collaborative networks that leverage data feedback loops. RESUMEN La descarbonización de los entornos urbanos entendida como la reducción de emisiones de gases de efecto invernadero (GEI) en las ciudades depende críticamente de acelerar la rehabilitación energética de las viviendas, especialmente en Europa (UN; BPIE, 2024). A pesar del aumento de las subvenciones públicas tras el lanzamiento del Pacto Verde Europeo (2019) y de la alineación de políticas a múltiples niveles orientadas a lograr la neutralidad climática para 2050, las tasas de rehabilitación energética residencial siguen siendo persistentemente bajas en las ciudades de la UE, particularmente en España, donde los esfuerzos de renovación continúan estando muy por debajo de los objetivos marcados por la UE. Esta brecha en la implementación motiva este estudio, que analiza la aplicación de políticas de rehabilitación energética de viviendas en Madrid como una lente para explorar los desafíos más amplios de los procesos de transformación urbana hacia la sostenibilidad. A través de un enfoque metodológico mixto, esta investigación combina datos cuantitativos para mapear la distribución socioespacial de las subvenciones a la rehabilitación energética a nivel de distrito y de barrio, con análisis cualitativo sobre el papel de los actores-intermediarios en la mediación entre los objetivos municipales y las decisiones privadas de las viviendas hacia la eficiencia energética. Basándonos en el marco conceptual de Martiskainen y Kivimaa (2017), proponemos una categorización de los intermediarios en tipos place-based y non place based, añadiendo una dimensión espacial para comprender mejor las funciones de los intermediarios en el ámbito de la rehabilitación de viviendas, y ejemplificamos esta tipología en nuestro estudio de caso en Madrid. Al integrar teorías de transformación urbana e intermediarios en el contexto de edificios cero emisiones, el estudio busca desarrollar un enfoque espacialmente fundamentado que permita comprender cómo las políticas se materializan de manera desigual en entornos urbanos heterogéneos. Los resultados indican que la recepción de subvenciones está desproporcionadamente concentrada en tres barrios socioeconómicamente vulnerables, caracterizados por condiciones edilicias deterioradas. Aunque estas zonas no...