Mitigating environmental impacts is an urgent challenge supported by (scientific) intensive care societies worldwide. However, making green choices without compromising high-quality care for critically ill patients may be challenging. The current paper describes a three-step approach towards green intensive care units. Starting with the measurement of environmental sustainability, intensive care units can identify hotspots, quantify the environmental impacts of products and procedures, and monitor sustainable progress. Subsequently, a multidisciplinary approach is proposed to improve environmental sustainability, including a collaboration of procurement specialists and healthcare professionals, using co-creation and green teams as efficient grassroots change agents. A context-specific approach for enhancing sustainable healthcare practices is key in order to fit local regulatory requirements and create support of professionals. A final step is to share results and create momentum, including publishing initiatives and participating in online (inter)national networks. Based on the core sustainability principles, this three-step approach towards green ICUs provides a valuable tool to professionals worldwide to facilitate change towards environmentally responsible intensive care units.