Personal and political action on climate change is traditionally thought to be motivated by people accepting its reality and importance. However, convincing the public that climate change is real faces powerful ideological obstacles(1-4), and climate change is slipping in public importance in many countries(.)(5,6) Here we investigate a different approach, identifying whether potential co-benefits of addressing climate change(7) could motivate pro-environmental behaviour around the world for both those convinced and unconvinced that climate change is real. We describe an integrated framework for assessing beliefs about co-benefits(8), distinguishing social conditions (for example, economic development, reduced pollution or disease) and comm...