This article by Dr Alessandro Massazza, Honorary Research Fellow at the Centre for Global Mental Health at the London School of Hygiene & Tropical Medicine, and now Research Manager in Evidence on the Mental Health Team at Wellcome Trust, explains how climate change affects mental health. The article outlines the links between the potential impact of climate-induced disasters on mental health, such as extreme weather events, heat, air pollution, and infectious disease. Alongside increasing climate anxiety and other emerging psychological reactions, it explores who is most at risk from mental health hazards resulting from climate change, and what can be done to mitigate and prevent such impacts.