Emotions are a powerful tool for changing people’s climate-related behaviors, but should be used carefully. This resource reviews research on emotions and climate change from the past five years, finding that people who are worried about climate change or have negative affect—an unpleasant gut feeling—toward it are more willing to engage both in mitigation behaviors like using public transport or saving electricity, as well as adaptation behaviors like purchasing insurance or seeking information about hazards. However, use caution when using messaging to invoke negative emotions about climate change. Creating intense climate anxiety may reduce people’s general well-being, and research in health communication has found that fear, without hope, may be counterproductive to behavior change. Instead, combine messages about the threat of climate change with “constructive hope” messaging, which focuses on feasible solutions and how individual and collection action can make a difference.