This ScienceBrief Review examines the links between climate change and extreme rainfall that can lead to severe flooding. It synthesises findings from more than 170 peer-reviewed scientific articles gathered using ScienceBrief. Climate change increases the frequency and intensity of extreme rainfall because a warmer atmosphere holds more water vapour that can rain out, sometimes over a short period. The movement of water vapour through the atmosphere, in storms, is also modified. Increases in extreme rainfall have been observed in many parts of the world. Extreme rainfall, in turn, can increase the chance of floods occurring and their magnitude in small and in urban catchments, severely impacting local populations and infrastructure. Extreme rainfall and associated flood hazards are projected to increase as global temperatures continue to rise.