The term Holy See refers to the supreme authority of the Church; i.e. the Central Government of the Catholic Church. The Holy See is an institution which has its own legal status and can, therefore, like any other state, sign treaties, establish its own laws and entertain diplomatic relations with foreign states.

The Vatican City State is the territory in which the Pope exercises his power. Established with the Lateran Treaty on 11 February 1929, it is, like the Holy See, a sovereign subject of universally recognised international public law.

The Pope is the Head of State. He has legislative, judicial and executive power.