The scientific community has expressed in no uncertain terms that the Earth’s climate is rapidly approaching a threshold, beyond which there are likely to be major and irreversible changes. The BMA recognises the important role doctors have in tackling climate change and promoting the public health benefits of low carbon living. As a member of the Climate and Health Council we support the call for healthcare professionals across the world to take action to limit climate change. With the direct threat to human health continuing to increase, the time to act is now.