This chapter addresses how concern for future generations has increasingly been included in legislative and policy measures since the early 1970s. The chapter asks whether it is meaningful to include future generations in the contemporary concept of citizenship and, if so, what this implies. The policy turn that started almost 50 years ago was motivated by questions about the potential consequences for future citizens’ welfare if present generations transfer irreversible environmental damage to them. The theoretical point of departure combines two strands of academic research: scholarship on citizenship and concerns for future generations. The chapter develops and applies analytical tools that bring future challenges closer to our lives, allowing us to better understand what intergenerational solidarity means and what it requires of us today if we should include future generations in our concept of citizenship. Empirically, the relevance of these concepts is evaluated by examining Norway as an example of how around 30 countries have included ecological protection clauses for future generations in their constitutions.