Climate change, biodiversity loss, and pollution are disrupting earth's biophysical systems, with adverse effects on local and global human health. Planetary health describes the inextricable link between human health and the health of earth's biophysical systems. There is urgent need for a stronger focus on planetary health among healthcare systems and radiology departments. Medical imaging is a substantial contributor to climate change, responsible for 0.8% to 1% of global greenhouse gas emissions. As demands for medical imaging continue to grow, so will the need for radiologists to provide leadership in environmentally sustainable medical imaging. Mitigation strategies targeting overall reductions in environmental impact are pivotal including reducing the energy consumption of medical imaging equipment and establishing a circular supply chain to reduce unnecessary waste. In addition, radiology departments will need to focus on adaptative measures which build resiliency to the impacts of climate change, some of which will be unavoidable. This review aims to define planetary healthcare in the context of radiology and provide a framework within which to consider specific actions to reduce the environmental footprint of medically necessary medical imaging.