[1] Organizations that receive permanent representatives from their member states include the United Nations, the World Trade Organization, NATO, the European Union, the African Union, the Organisation of Islamic Cooperation, and the Organization of American States.
Permanent representatives can be sent to subunits or field offices of an organization.
For example, in addition to the permanent representatives sent to the United Nations headquarters in New York City, UN member states also appoint permanent representatives to other UN offices, such as those in Geneva, Nairobi, and Vienna.
[2] However, although a permanent representative typically holds the diplomatic rank of an ambassador, because they are accredited to an international organisation, their official title is permanent representative.
[3] Some international organizations, such as UNESCO, use the title permanent delegate to refer to the head of a diplomatic mission accredited to them.