If the global healthcare sector were a country, it would be the fifth-largest carbon emitter, also producing massive volumes of waste. A revolutionary transition to an environmentally sustainable model of healthcare is required. Decarbonisation efforts are initially focused on transitioning to renewable energy sources and improving energy efficiency in healthcare facilities (Scopes 1 and 2). One of the major challenges is to reduce the carbon intensity of the broader healthcare sector, especially operational and supply chain-related emissions, which represent 71% of the sector’s worldwide emissions (Scope 3). This comment briefly describes the connections between the healthcare sector and climate change and describes several high-impact decarbonisation opportunities, focusing on transitioning from current resource and waste-intensive procurement models and highlighting the planetary co-benefits of fostering low-emissions healthcare. To succeed, this transition will require high-level advocacy and policy changes supported by international collaboration at the global level.