
The following outline is provided as an overview of and introduction to Vatican City:

The Australian Ambassador to the Holy See was first appointed in 1973. The first nominee for this position was Dudley McCarthy, who was also the ambassador to Spain, but the Vatican refused to accept the nomination on the grounds that McCarthy had been divorced. The appointment was subsequently attached to the office of the Ambassador to the Netherlands, Denmark, Turkey, Ireland, Malta, Sweden and Switzerland, before Tim Fischer was appointed as the first permanent resident ambassador to the Holy See in 2008. In 1986, Sir Peter Lawler had been appointed resident ambassador for four months prior to Pope John Paul II's visit to Australia.

The Ambassador of the United States to the Holy See is the official representative of the United States of America to the Holy See, the leadership of the Roman Catholic Church. The official representation began with the formal opening of diplomatic relations with the Holy See by President Ronald Reagan and Pope John Paul II in 1984.

This is a list of diplomatic missions of the Holy See. Since the fifth century, long before the founding of the Vatican City State in 1929, papal envoys have represented the Holy See to foreign potentates. Additionally, papal representatives known not as nuncios but as apostolic delegates ensure contact between the Holy See and the Catholic Church in countries that do not have diplomatic relations with the Holy See.
This page lists diplomatic missions accredited to the Holy See, the government of the Catholic Church and the temporal ruler of the Vatican City. 87 countries currently maintain embassies to the Holy See. The Vatican City State, over which the Holy See is sovereign, is the smallest independent entity in the world and its size renders any resident diplomatic community impractical. Therefore, all embassies to the Holy See are located in Rome making Vatican City one of only two sovereign states, the other being Liechtenstein, with no resident embassies located within its territory. This leads to the situation that the Embassy of Italy to the Holy See is based on its home territory, which is also the case for Iceland, Latvia, and Sweden. This also means that an embassy of the Republic of China to the Holy See is located in Italy, which does not recognize the Republic of China.

Pope John Paul II was celebrated during his lifetime and later posthumously with several honours and as the namesake of several places and institutions. Such places often bear the name John Paul II but newer institutions are using the name John Paul the Great.

Telephone numbers in Vatican City are integrated into the Italian telephone numbering plan: ITU-T has assigned country code +379 to Vatican City, but this is not in use.

The Ambassador of the United Kingdom to the Holy See has held that title since 1982. Before that the British heads of mission to the Holy See were styled Attaché resident at Rome and Envoy Extraordinary and Minister Plenipotentiary.