A protective security unit typically provides policing, security, intelligence and bodyguard services for sovereigns and politicians. It can be contrasted with a security service, which provide protective security intelligence such as the British Security Service; and a guards regiment for the defence of the Sovereign and the metropolis. Examples of these include the Household Division.
There are also distinct non-combat personal bodyguards which serve as ceremonial guards and personal attendants (such as the Gentlemen at Arms, the Yeomen of the Guard, the Royal Company of Archers, and the Company of Pikemen and Musketeers of the Honourable Artillery Company, as well as the Corps of Serjeants at Arms, the Gold Stick and Silver Stick, and the High Constables and Guard of Honour of the Palace of Holyroodhouse).
Well-known examples include the Royalty and Diplomatic Protection Department of the London Metropolitan Police, the United States Secret Service, and the Diplomatic Security Service of the United States Department of State. Typically they provide security and any ceremonial effect is not per se an objective.
In the Republic of Ireland, the Garda Síochána (Irish Police) Special Detective Unit (SDU) and Emergency Response Unit (ERU) provide armed protection and transport for the Irish President, Michael D. Higgins and the Taoiseach (Prime Minister) Simon Harris. The unit also provides protection for senior government officials, diplomatic staff and visiting dignitaries to Ireland.
In Northern Ireland the Police Service of Northern Ireland (PSNI) Close Protection Unit (CPU) provides protection to visiting dignitaries on visits to Northern Ireland as well as to the Secretary of State, members of the Royal Family, UK Government ministers and senior members of the Northern Ireland Executive, the region’s devolved administration.
Among oriental Asian countries, during the Imperial era, the Imperial Guards Division (Konoe Shidan, 近衛師団) under the Imperial Japanese Army was responsible for the Emperor’s security & the guarding of his residential palaces much like the British’s Household Divison. After the defeat of Japan in World War II and the demilitarisation of Japan, that responsibility was handed over to the Tokyo Metropolitan Police Department and since 1954, the National Police Agency. The current Imperial Guards are made up of police officers of the Imperial Guard Headquarters (Kōgū-Keisatsu Honbu, 皇宮警察本部). On the contrary, VIP close protection of the Prime Minister and any visiting foreign diplomats is delegated to the Security Police.
Among western countries of predominantly ethnic Chinese population, Taiwan’s VIP close protection force is the Special Service Command Center under the National Security Bureau, while Hong Kong has the VIP Protection Unit, formerly Section G, Division 4 or G4. In Singapore, that responsibility is given to the Police Security Command.
In South Korea, close protection of the president is given to the Presidential Security Service.