From a normative point of view, neither sustainable development nor intergenerational justice in general (i.e. apart from the environmental aspect) is explicitly anchored in the German Constitution (Grundgesetz) as a legal principle or state aim. Nevertheless, future generations are not unprotected by the Constitution. This paper argues that future generations have no subjective rights, but the constitutional guarantee of fundamental rights already contains an objective legal duty (“Schutzpflicht”) of the state to protect life and health of future individuals today.