The past two decades have seen the emergence of a new field of enquiry in meteorology and climate: quantifying the contribution of greenhouse gas emissions to observed weather and climate events. We have also seen considerable progress in communicating the relationship between climate change and extreme weather, from the dismissive “weather is not climate” twenty years ago to a much more sophisticated probabilistic understanding today. The late Professor Geert Jan van Oldenborgh, of the Royal Netherlands Meteorological Institute and Visiting Professor in Atmospheric, Oceanic and Planetary Physics in Oxford, played a central role in both of these developments, particularly as one of the founders of the World Weather Attribution project. In a special symposium, three of Geert Jan’s colleagues reflect on the progress that has been made in this challenging and often controversial field and discuss priorities for the future.