The Lancet Commission on Sustainable Healthcare (LCSH) is an expert collaborative of academics, ministries of health, and sustainable healthcare program leaders tackling issues of appropriate consumption and environmental emissions from healthcare activities to define best practices for low-carbon, sustainable, and resilient care. The LCSH works to develop evidence-based guidance and standardized indicators, informing implementation policies across diverse resource settings and engaging diverse stakeholders, including policy makers, industry leaders, healthcare administrators, health professionals, educators, and the population at large. Following the 2025 launch of our original work in the Lancet, the LCSH will disseminate report outputs through a social media campaign, at major global events, and via a speaking tour, with a focus on strategically-designed toolkits adapting our empirical evidence to guide implementation in real-world healthcare environments. Our work will form the basis of a new division of the Lancet Countdown on Health and Climate Change, allowing annual monitoring and reporting of relevant metrics toward sustainable health systems transformation.