Emergency clinicians worldwide are demonstrating increasing concern about the effect of climate change on the health of the populations they serve. The movement for sustainable healthcare is being driven by the need to address the climate emergency. ⋯ In this article, we consider the implications for emergency medicine of climate change, and suggest ways to improve environmental sustainability within emergency departments. We identify examples of sustainable clinical practice, as well as outlining research proposals to address the knowledge gap that currently exists in the area of provision of environmentally sustainable emergency care.