Although many today acknowledge that we should act up against climate change for the sake of future generations, it is not obvious why exactly we should do so. Without any plausible moral reasons to move us to care for future generations, climate policies will lack broad acceptance and compliance. This then hinders its legitimacy and effectiveness. Climate change is the perfect exemplar of an intergenerational moral problem. Many possible theoretical underpinnings for intergenerational justice have been the topic of ethical discourse, but one notion that is popular in policymaking has been left on the side in these theoretical discussions: solidarity. In this thesis I will show that solidarity is a valuable addition to moral theories and policies. Solidarity is not only able to face the challenges that established theories of intergenerational justice are confronted with, the concept might also provide moral motivation – which is of great important to climate action.