We discuss prior findings that enhancing perceptions of collective efficacy encourages pro environmental behavior. We suggest that collective efficacy manipulations affect pro-environmental intentions through increasing both collective and self-efficacy. Four experiments conducted in Germany and Australia demonstrated that collective efficacy manipulations can increase pro-environmental intentions by increasing the perception that one's group and, through this, the self is capable of effecting change. We also provide evidence that collective efficacy manipulations only work when they simultaneously raise self-efficacy. Our findings contribute to the environmental literature by showing the mechanisms through which group efficacy appeals work. Our findings also support theorizing on group based control by showing that personal control can be derived from group sources. (C) 2016 Elsevier Ltd. All rights reserved.