As their first steps into the profession, doctors recite the Hippocratic Oath as a reminder of the ethical principles that guide their practice. Calling upon various Greek gods, new physicians swear to “abstain from all intentional wrongdoing and harm.”

Yet today, the healthcare sector faces a profound ethical contradiction. According to a report by Health Care Without Harm, in collaboration with Arup, healthcare is responsible for 4.4% of global net greenhouse gas emissions, or roughly 2 gigatons of carbon dioxide equivalent.