Multilateral diplomacy
Furthermore, outside this traditional pattern of bilateral diplomacy, as a rule on a permanent residency basis (though sometimes doubling elsewhere), certain ranks and positions were created specifically for multilateral diplomacy:
An ambassador-at-large is equivalent to an ambassador and assigned specific tasks or region in which they are assigned various assignments aimed at multi track diplomacy.
A permanent representative is the equivalent of an ambassador, normally of that rank, but accredited to an international body (mainly by member—and possibly observer—states), not to a head of state.
A resident representative (or sometimes simply representative) is also a member of the diplomatic corps, but is below the rank of ambassador. A representative is accredited by an international organization (generally a United Nations agency, or a Bretton Woods institution) to a country's government. The resident representative typically heads the country office of that international organization within that country.
A special ambassador or honorary ambassador is a government's specialist diplomat in a particular field, not posted in residence, but often traveling around the globe.
The U.S. trade representative (USTR) is an ambassador of Cabinet rank, in charge of U.S. delegations in multilateral trade negotiations (since 1962). The USTR's special agricultural negotiator also typically holds an ambassadorial appointment.
Special envoys have been created ad hoc by individual countries, treaties and international organizations including the United Nations. A few examples are provided below:
Australia
The Australian Department of Foreign Affairs and Trade maintains a variety of special interest ambassador and envoy positions including the ambassador for counter-terrorism and the ambassador for the environment.
Belgium
In 2005, former cabinet member Pierre Chevalier served as Special Envoy of the Organization for Security and Co-operation in Europe presidency to mediate in the Gazprom natural gas-pipeline crisis involving Russia, Ukraine, and the European Union. In addition, Princess Astrid of Belgium has served as Special Envoy of the Anti-Personnel Mine Ban Convention or Ottawa Treaty, to promote the formal prohibition of landmines and the rights of the survivors of said weapons.
Bosnia and Herzegovina
A sui generis case is the High Representative for Bosnia and Herzegovina
European Union
appointed various special representatives (some regional, some thematic); e.g., in 2005—as a response to events in Kyrgyzstan and Uzbekistan—the Council of the EU appointed Jan Kubis as its Special Representative for Central Asia.
India
During the 2006 democracy movement in Nepal, India sent on April 18 Karan Singh, who is related to royalty in both predominantly Hindu countries, as Special Envoy to neighbouring Nepal, where increasingly violent opposition started its successful challenge of the king's autocratic rule. Another instance was during the 2009 Copenhagen climate change summit, India appointed senior diplomat Shyam Saran as a special envoy to coordinate the negotiating position of the BASIC countries.
Niue
The Niue Government appoints special envoys to expand Niue's presence internationally. Envoys include
Special Envoy to Niue for COP26 2021 United Nations Climate Change Conference
Special Envoy to Niue for the 2022 Japan State Funeral for the former Japan Prime Minister Shinzo Abe
Pakistan
Prime Minister Nawaz Sharif appointed ambassador Javed Malik as Pakistan's special envoy for trade and investment based in the GCC Gulf region with a diplomatic rank of an ambassador
United Kingdom
Appointed special envoys from time to time.
United States
appointed numerous special envoys including a special envoy for Northern Ireland with the diplomatic rank of ambassador to help with the Northern Ireland peace process. Special envoys have also been appointed for Afghanistan, Yemen, Sudan, Syria, Middle East peace, Eurasian energy, climate change, and human rights in North Korea. Other posts include special representative, special advisor, and special coordinator.
UN Secretary-General
The Secretary-General of the United Nations personally mandates special envoys for a particular field, including:
United Nations Special Envoy for HIV/AIDS in Africa
United Nations Special Envoy on Climate Change
United Nations Special Envoy for Kosovo
United Nations Special Envoy for Darfur
United Nations Special Envoy for Refugees
UNESCO
The director-general of UNESCO appoints special envoys who can use their talents and renown to further the organization's ideals and action. Envoys include:
Special Envoy for Basic and Higher Education Sheikha Mozah bint Nasser al-Missned of Qatar
Special Envoy for Water Prince Talal bin Abdulaziz al Saud
Special Envoy on Literacy for Development Princess Laurentien of the Netherlands