The 6th Assessment of the Intergovernmental Panel on Climate Change sounded its most piercing red alert ever – we are in a climate crisis . In this Special Issue of the Journal of Climate Change and Health, professionals in the healthcare arena share their experiences and solutions for mitigating and adapting to the rapidly progressing changes around us. Why are we focusing on healthcare professionals? Why us? Why now?
Climate change and environmental decline are global problems of unprecedented magnitude and complexity, of the type sometimes called “wicked” problems or “grand challenges” that cross multiple scales, disciplines, systems, societal levels, and geographic locations  . The healthcare sector's contribution to this most pressing of public health problems is significant, accounting for approximately 10% of the annual greenhouse gas emissions in the United States and significant amounts of total emissions and other pollutants globally  . Additionally, we are responsible for keeping health systems functioning through the floods, fires, severe weather and heat emergencies that we already experience with increasing frequency and intensity, and which are forecast to worsen under all current emission scenarios. As tempting as it may be to try to leave this crisis to politicians, governments, international agencies, treaties, and big multinational corporations to solve, healthcare professionals have a unique responsibility and outsized platform for immediate and meaningful action.