Resident Commissioner is the title of several, quite different types of Commissioner in overseas possession or protectorate of the British Crown or of the United States.
British Empire and Commonwealth 
Resident Commissioners appointed by the British crown have in common that they, but also most otherwise styled Commissioners, reside in the territorial unit they are in charge of.
Notably in certain complex colonial units within the British Empire, the High Commissioner to whom was given the highest 'regional' supervision (either residing in one of the constitutive territories, e.g. in the British Western Pacific Territories (BWPT), first by the Governor on Fiji, then from 1952 onwards on the Solomon Islands; or even in a neighbouring colony, e.g. the Governor of the Straits Settlements as High Commissioner for the Federated Malay States) would commonly be represented in territories not comprising his residence by a Resident Commissioner, though in some places (including some of the Federated Malay States) similar officials were formally styled as Residents, a more diplomatic title; otherwise another type of official was also possible (e.g. the British Consul in the protected state of Tonga, a Polynesian kingdom; an Administrator on Nauru; a mere Chief Magistrate on tiny Pitcairn). In some cases one could compare his task to the Lieutenant-governor of a minor colony, especially as the High Commissioner indeed could be a British colonial Governor doubling as such.
In the British Western Pacific Territories this was the case for:
- The British Solomon Islands from 1893 until they got a Governor (who also became the High Commissioner) in 1952.
- Since 9-16 October 1892 on the Gilbert and Ellice Islands (British protectorate, presently in Kiribati), i.e. before they became a colony within the BWPT in 1916 (since 1916 including the Union Group protectorate, later a separate state called Tokelau).
- The Cook Islands, since the 11 June 1901 incorporation into New Zealand (previously there was a British Resident).
- Niue since 1901 (later under high commissioners) soon annexed to the dominion of New Zealand (1901-1904 as part of the Cook Islands).
- A special case were the New Hebrides, for these were an Anglo-French colonial condominium, so he had a French colleague styled Résident, subordinate to France's haut commissaire (high commissioner) in the Pacific Ocean (from 22 March 1907 the Governor of New Caledonia); both were abolished at the independence of the Republic of Vanuatu in 1980.
While the post of High commissioner for Southern Africa (HCSA) was held 27 January 1847 - 31 May 1910 by the Governors of the Cape Colony, then till 6 April 1931 by the Governors-general of South Africa, after that date filled separately till 1963, there have been resident representatives in the constituent territories:
- In (British) Bechuanaland, after a few Deputy - and Special Commissioners, there were Resident Commissioners since it was made dependent on the HCSA on 9 May 1891; in 1892-1923 there were also two Assistant Commissioners, for the North and the South respectively.
- In the British Swaziland protectorate, since it was dependent on the HCSA in 1902 (before administered through Transvaal, under an Administrator); afterwards both got a separate Commissioner.
- Since on 18 March 1884 Basutoland became a separate colony, as one of the High Commission Territories, it got its Resident Commissioner, instead of a Cape Government Agent (since it became a British protectorate in 1868).
United States 
- The Resident Commissioner of Puerto Rico does not reside there but represents the U.S. Commonwealth in the continental United States, particularly in the capital of Washington, DC. He or she represents Puerto Rico in the United States House of Representatives, where the Resident Commissioner has a status equivalent to a territorial delegate, as well as before executive departments.
- Resident Commissioners from the Philippines held a similar position when the Philippines was a United States territory and then Commonwealth. The position was originally created by the Philippine Organic Act of 1902 with the first commissioners serving from 1905. The position ended with Philippine Independence in 1946.
- In most other U.S. overseas (and historically pre-state) territories, a similar representative position is styled Delegate.
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