Zotova, OlenaSazdovski, IlijaMartinez, Miguel AngelDasandi, NiheerOliva, CarlaPujadas i Rovira, JordiIniesta Blasco, Cristinade’Donato, FrancescaRoychoudhury, MurchanaChen-Xu, JoséNilsson, MariaTonne, Cathryn2025-09-092025-09-092025Zotova O, Sazdovski I, Martinez MA, Dasandi N, Oliva C, Pujadas i Rovira J, et al. Realizing a carbon-neutral healthcare system: a co-created Theory of Change in Catalonia, Spain. Oxford Open Climate Change. 2025;5(1):kgaf018. DOI: 10.1093/oxfclm/kgaf0182634-4068http://hdl.handle.net/10230/71170Amid growing efforts to mitigate climate change in healthcare systems, there is a need to better understand the complex social and political processes by which a healthcare system can progress towards “net zero” goals. We aimed to gather stakeholders’ perspectives to explain this process by applying a qualitative Theory of Change (ToC) co-creation methodology in the subnational healthcare system of Catalonia, Spain. Iterative virtual focus group interviews and written feedback rounds gathered the perspectives of 12 stakeholders, including researchers, government officials and healthcare professionals working in the Catalan healthcare system and/or climate action. Thematic and axial coding on focus group transcripts identified themes, categories and relationships. A ToC consisting of a sequence of nearly two hundred events envisioned by stakeholders to reach a long-term desired change of a “smart net zero” healthcare system was developed. The need for simultaneous top-down and bottom-up change was recognized, with identification of key stakeholder groups. Events were categorized into four “core change pathways” (policy, industry, healthcare institutions’ and healthcare workers’ pathways) and six “supporting processes” (governance, participation and collaboration, finance, digitalization, knowledge production and knowledge dissemination). The sequence of events in every pathway was further categorized into five stages of change: motivation, commitment, planning, implementation, and monitoring and evaluation. A ToC approach was useful to understand context-specific political, logistical, and social constraints and opportunities for different types of stakeholders to contribute to change towards a “net zero” healthcare system.application/pdfeng© The Author(s) 2025. Published by Oxford University Press. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/articlehttp://dx.doi.org/10.1093/oxfclm/kgaf018Climate changeMitigationHealthcareHealth systemTheory of ChangeCarbon footprintSocial changeinfo:eu-repo/semantics/openAccess