Many environmental problems are caused by and can be ameliorated by human behavior. Psychologists, with a focus on human behavior, are uniquely suited to understand when and why people perform (or fail to perform) pro-environmental actions. Our research uses a social psychological lens to investigate the characteristics of both the situation and the individual that facilitate PEBs as well as the psychological effects of performing pro-environmental behaviors (PEBs). We are interested in the role of identity, consistency, licensing, and the single action bias in the performance and maintenance of pro-environmental behaviors. We conduct experiments on these issues in the lab and the field.