Climate change is leading to variations in weather patterns and an apparent increase in extreme weather events, including heat-waves. Recent heat-waves in the WHO European Region have led to a rise in related mortality but the adverse health effects of hot weather and heat-waves are largely preventable.This guidance results from the EuroHEAT project on improving public health responses to extreme weather/heatwaves, co-funded by WHO and the European Commission. It explains the importance of the development of heat–health action plans, their characteristics and core elements, with examples from several European countries that have begun their implementation and evaluation.