Climate change is the biggest threat to humanity in the modern day. Almost every sector in our society has contributed to the climate crisis in one way or another — and the health care system is no exception. We are only just beginning to understand the ways in which human health can be profoundly impacted by the state of our planet. The purpose of this guidebook is not to serve as a comprehensive roadmap to achieving a net-zero ICU. Rather, it serves as a primer to kickstart the process of achieving a more sustainable practice.