International Civil Aviation Organization
The International Civil Aviation Organization is a specialized agency of the United Nations that coordinates the principles and techniques of international air navigation, and fosters the planning and development of international air transport to ensure safe and orderly growth. The ICAO headquarters are in the of Montreal, Quebec, Canada.
The ICAO Council adopts standards and recommended practices concerning air navigation, its infrastructure, flight inspection, prevention of unlawful interference, and facilitation of border-crossing procedures for international civil aviation. ICAO defines the protocols for air accident investigation that are followed by transport safety authorities in countries signatory to the Convention on International Civil Aviation.
The Air Navigation Commission is the technical body within ICAO. The commission is composed of 19 commissioners, nominated by the ICAO's contracting states and appointed by the ICAO Council. Commissioners serve as independent experts, who although nominated by their states, do not serve as state or political representatives. International Standards and Recommended Practices are developed under the direction of the ANC through the formal process of ICAO Panels. Once approved by the commission, standards are sent to the council, the political body of ICAO, for consultation and coordination with the member states before final adoption.
ICAO is distinct from other international air transport organizations, particularly because it alone is vested with international authority : other organizations include the International Air Transport Association, a trade association representing airlines; the Civil Air Navigation Services Organisation, an organization for air navigation service providers ; and the Airports Council International, a trade association of airport authorities. In addition there are several regional civil aviation commissions, such as the Latin American Civil Aviation Commission who focus on challenges and growth in specific regions.
History
20th century
In the early 20th Century, the International Telecommunication Union met to discuss and implement one of the first internationally agreed upon standards relating to aviation, country-specific prefixes for aircraft callsigns. The first convention was held in 1903 in Berlin, Germany, but no agreements were reached among the eight countries that attended. At the second convention in 1906, also held in Berlin, twenty-seven countries attended. The third convention, held in London in 1912, allocated the first radio callsigns for use by aircraft. Following this, at the Paris Convention of 1919, a forerunner to ICAO named ICAN was established, the International Commission for Air Navigation. ICAN continued to operate until 1945.The Convention on International Civil Aviation, also known as the Chicago Convention, in Chicago, was signed by 52 countries on 7 December 1944. Under its terms, a Provisional International Civil Aviation Organization was to be established, to be replaced in turn by a permanent organization when twenty-six countries ratified the convention. PICAO began operating on 6 June 1945, replacing ICAN. The 26th country ratified the convention on 5 March 1947 and, consequently, PICAO held its last session from 29 April 1947 until 7 May 1947, with the Convention on International Civil Aviation coming into force on 4 April 1947.
In October 1947, ICAO became an agency of the United Nations under its Economic and Social Council.
21st century
In April 2013, Qatar offered to serve as the new permanent seat of the Organization. Qatar promised to construct a massive new headquarters for ICAO and to cover all moving expenses, stating that Montreal "was too far from Europe and Asia", "had cold winters", was hard to attend due to the Canadian government's slow issuance of visas, and that the taxes imposed on ICAO by Canada were too high. According to The Globe and Mail, Qatar's invitation was at least partly motivated by the pro-Israel foreign policy of Canadian prime minister Stephen Harper. Approximately a month later, Qatar withdrew its bid after a separate proposal to the ICAO's governing council to move the ICAO triennial conference to Doha was defeated by a vote of 22–14.In June 2014, the Montreal Metro station closest to the ICAO headquarters was renamed Square-Victoria–OACI, celebrating the 70th anniversary of ICAO's presence in Montreal.
Taiwan controversy
In January 2020, ICAO blocked several Twitter users, including think-tank analysts, U.S. Congressional staff, and journalists, who mentioned Taiwan in tweets related to ICAO. Many of the tweets were related to the COVID-19 pandemic and Taiwan's exclusion from ICAO safety and health bulletins due to pressure from China. In response, ICAO issued a tweet stating that publishers of "irrelevant, compromising and offensive material" would be "precluded".Since that action, the organization has followed a policy of blocking anyone asking about it.
The United States House Committee on Foreign Affairs harshly criticized ICAO's perceived failure to uphold principles of fairness, inclusion, and transparency by silencing non-disruptive opposing voices. Senator Marco Rubio also criticized the move. The Taiwanese Ministry of Foreign Affairs and legislators criticized the move, with MOFA head Jaushieh Joseph Wu tweeting in support of those blocked.
In January 2020, Anthony Philbin, Chief of Communications for the ICAO Secretary General, defended ICAO's actions, stating, "We felt completely justified in taking steps to protect the integrity of the information and discussions that our followers reasonably expect from our feeds." In exchanges with the International Flight Network, Philbin refused to acknowledge the existence of Taiwan.
On 1 February 2020, the United States Department of State issued a press release heavily criticizing ICAO's actions, characterizing them as "outrageous, unacceptable, and not befitting of a UN organization."
North Korea controversy
On 2 May 2025, the ICAO Council expressed grave concern over ongoing Global Navigation Satellite System radio frequency interference in the Incheon Flight Information Region, incidents that have persisted since 2 October 2024, and are attributed to North Korea, officially known as the Democratic People's Republic of Korea. The Council emphasized that such interference endangers international air navigation safety and violates the principles of the Chicago Convention. It strongly urged the DPRK to adhere to its international obligations and prevent future occurrences. Given the severity of the situation, the Council is considering reporting the matter to the 42nd Session of the ICAO Assembly in September 2025, as per Article 54 of the Convention, and will continue to monitor developments closely.Statute
The 9th edition of the Convention on International Civil Aviation includes modifications from years 1948 up to 2006. ICAO refers to its current edition of the convention as the Statute and designates it as ICAO Document 7300/9. The convention has 19 Annexes that are listed by title in the article Convention on International Civil Aviation.Membership
, there are 193 ICAO members, consisting of 192 of the 193 UN members, plus the Cook Islands.Despite Liechtenstein not being a direct party to ICAO, its government delegated Switzerland to enter into the treaty on its behalf in 1947, and the treaty is applicable in the territory of Liechtenstein.
Exclusion of Taiwan
The Republic of China was a founding member of ICAO. Following its retreat to Taiwan, it was eventually replaced by the People's Republic of China as the legal representative of China in 1971.In 2013, Taiwan was for the first time invited to attend the ICAO Assembly, at its 38th session, as a guest under the name of "Chinese Taipei"., it has not been invited to participate again, due to renewed PRC pressure.
The host government, Canada, supports Taiwan's inclusion in ICAO. Support also comes from Canada's commercial sector with the president of the Air Transport Association of Canada saying in 2019 that "It's about safety in aviation so from a strictly operational and non-political point of view, I believe Taiwan should be there."
Council
The ICAO Council is elected by the Assembly every three years and consists of 36 members elected in three groups. The present council was elected in September 2025.The structure of the present Council is as follows:
| Group I | Group II | Group III |
StandardsICAO also standardizes certain functions for use in the airline industry, such as the Aeronautical Message Handling System. This makes it a standards organization.Each country should have an accessible Aeronautical Information Publication, based on standards defined by ICAO, containing information essential to air navigation. Countries are required to update their AIP manuals every 28 days and so provide definitive regulations, procedures and information for each country about airspace and airports. ICAO's standards also dictate that temporary hazards to aircraft must be regularly published using NOTAMs. ICAO defines an International Standard Atmosphere, a model of the standard variation of pressure, temperature, density, and viscosity with altitude in the Earth's atmosphere. This is useful in calibrating instruments and designing aircraft. The standardized pressure is also used in calibrating instruments in-flight, particularly above the transition altitude. ICAO is active in infrastructure management, including communication, navigation and surveillance / air traffic management systems, which employ digital technologies in order to maintain a seamless global air traffic management system. |
Australia