Climate change is no longer a problem for future generations and the impact is already taking a toll in many parts of the world. Climate change has already caused substantial, and increasingly irreversible, damage to ecosystems. All these issues combined will inevitably lead to an increase in human suffering and forced displacement. This has significant ramifications for health care systems. In this editorial we outline how climate change is already impacting both physical and mental health. Health professionals have a role to play in addressing this great challenge of our time. Health professionals should reflect on how to promote means of climate change mitigation and adaptation within their spheres of influence – clinical, education, advocacy, administration, and research.