The key to the notion of sovereignty lies in the idea of ultimate authority. What is it for a source of authority to be ultimate? An authority may be ultimate if it is the highest in a hierarchy of authorities. Such an authority may also be final : there is no further appeal after it has spoken (it has ‘the last word’). Lastly, an ultimate authority may be one which is supreme in a particular sense : it has authority over all other authorities in its realm. The state’s authority is sovereign in this sense ; it takes precedence over competing authorities (e.g. corporate, syndicate, church, conscience). Summarizing , then, sovereignty is the highest, and supreme political authority within a modern territorial realm.