While the Air Transport Association sets the standards and rules of U.S. domestic airlines, the International Air Transport Association (IATA) sets standards between nations. IATA�s main function is the economic regulation of international air transportation, in particular international rates and fares that are subject to unanimous resolutions of the carriers, provided that the countries do not object.

IATA is a voluntary organization open to any scheduled air carrier whose home country is a member or eligible candidate of the International Civil Aviation Organization (ICAO). Its main function is the economic regulation of international air transportation, in particular international rates and fares that are subject to unanimous resolutions of the carriers, provided that the countries do not object.

IATA has served the international and global travel industry since 1919. It has a membership of over 275 airlines from 143 countries. It has represents 90,000 accredited travel agencies in 209 countries.

IATA seeks to be a neutral, intermediary to develop standards which facilitate cooperation among travel industry enterprises. IATA has standardized the air ticket system and the travel agent appointment system, and created a financial dispute settlement system. IATA is also the provider of the three letter airline city codes system and a two letter airline code system recognized as the standards for communicating airport and flight information the world over.

In 1979 IATA was reorganized into two divisions:

Trade Association dealing with technical, legal, financial, traffic services and most agency matters

Tariff Coordination addressing passenger fares and cargo rates, and agents' commissions. Approximately 100 Members, including the world's largest airlines, participate in Tariff Coordination.