A state that answers to no higher earthly authority within its territory possesses sovereignty. Internal sovereignty means supremacy over domestic affairs; external sovereignty means independence from outside control.

Sovereignty emerged as a central concept with the modern state system. It underpins the legal equality of states, the principle of non-intervention, and the authority to make final decisions on law and policy. In practice, sovereignty is always qualified by treaties, economic interdependence, and power asymmetries.

Globalization, human-rights norms, and international organizations have intensified debates over whether sovereignty is eroding or merely being exercised through new cooperative forms. Secessionist movements claim sovereignty for subnational peoples; established states resist those claims. The vocabulary of sovereignty remains indispensable for describing both the rights states assert and the limits they encounter.

• Supreme authority within a territory
• Internal control and external independence
• Foundation of the modern state system
• Qualified in practice by interdependence