The concept of sovereignty implies the self-determination of political power. It does not entail, however, any assumption either about whether this power is legitimate and, if so, how its legitimation is realized, or about the extension of the power that is supposed to be sovereign. Thus, political power could be perfectly indifferent to democratic legitimacy or to global injustice, while being nevertheless recognized as sovereign. Since the concept of sovereignty was originally developed within the context of a paradigm of social, political and legal order according to which the well-ordered society is limited in its extension and governed through a top-down chain of authority, it is not surprising that questions like democratic legitimacy and global justice were simply ignored by its supporters. Yet, three major paradigmatic revolutions took place that have shaken the conceptual foundations of social order on which the idea of sovereignty was originally built, so that three corresponding challenges were posed to its traditional understanding. A first paradigmatic revolution from holism to individualism shifted the barycentre of the well-ordered society from a kind of predetermined unity of the community to the individuals. As a result, the legitimacy of sovereign power could no longer be taken for granted because of the passive acceptance of tradition or of an alleged mythological or divine “truth”. On the contrary, it was expected, from then on, that the sovereign power was legitimated “bottom-up”, i.e. by the reflexive consent of the citizens. According to this premise, absolutistic sovereignty was transformed into popular sovereignty. A second paradigmatic revolution expanded the boundaries of the well-ordered society to include, at least potentially, the whole humankind. Consequently, if it was to be justified, sovereign power had to adapt to the new situation by accepting global responsibility. The third and more recent paradigmatic revolution regarding the idea of the well-ordered society finally affected the assumption that the well-ordered society should always be conceived of as unitary, i.e., as a hierarchical and self-reliant pyramid of norms and institutions. Instead, following some contemporary theories, a society can also be considered well-ordered if composed of a plurality of systems of norms and institutions which are not related to one another in a hierarchical form, but through horizontal interconnections. Within the context of legal and institutional pluralism, sovereignty itself has to differentiate, so as to express the variety of individual cultural belongings and political affiliations that characterize the postnational constellation. In conclusion, if sovereignty is to be seen as a value, its concept has to meet the challenges deriving from all three major paradigmatic revolutions, which means it has to become consistent with the normative requirements of democratic government as well as with the variable geometry and the global responsibility of a necessarily interconnected world.