The Federal Aviation Administration (FAA) of the United States is a national authority with powers to regulate all aspects of civil aviation. These include the construction and operation of airports, air traffic management, the certification of personnel and aircraft, and the protection of U.S. assets during the launch or re-entry of commercial space vehicles.

The Air Commerce Act of May 20, 1926, is the cornerstone of the federal government's regulation of civil aviation. This landmark legislation was passed at the urging of the aviation industry, whose leaders believed the airplane could not reach its full commercial potential without federal action to improve and maintain safety standards. The Act charged the Secretary of Commerce with fostering air commerce, issuing and enforcing air traffic rules, licensing pilots, certifying aircraft, establishing airways, and operating and maintaining aids to air navigation. The newly created Aeronautics Branch, operating under the Department of Commerce assumed primary responsibility for aviation oversight.

The FAA gradually assumed additional functions. The hijacking epidemic of the 1960s had already brought the agency into the field of civil aviation security. In response to the hijackings on September 11, 2001, this responsibility is now primarily taken by the Department of Homeland Security. The FAA became more involved with the environmental aspects of aviation in 1968 when it received the power to set aircraft noise standards. Legislation in 1970 gave the agency management of a new airport aid program and certain added responsibilities for airport safety. During the 1960s and 1970s, the FAA also started to regulate high altitude (over 500 feet) kite and balloon flying.

The Federal Aviation Administration location identifier (FAA LID) is a three- to five-character alphanumeric code identifying aviation related facilities inside the United States, though some codes are reserved for, and are managed by other entities. For nearly all major airports, the assigned identifiers are alphabetic three-letter codes, such as SFO for San Francisco International Airport. Minor airfields are typically assigned a mix of alphanumeric characters, such as 8N2 for Skydive Chicago Airport and 0B5 for Turners Falls Airport. Private airfields are assigned a four-character identifier, such as 1CA9 for Los Angeles County Fire Department Heliport. The location identifiers are coordinated with the Transport Canada Identifiers.

In general, the FAA has authority to assign all three-letter identifiers (except those beginning with the letters K, N, W, and Y), all three and four character alphanumeric identifiers, and five-letter identifiers for the United States and its jurisdictions. The Department of the Navy assigns three-letter identifiers beginning with the letter N for the exclusive use of that Department. Transport Canada assigns three character identifiers beginning with Y. The block beginning with letter Q is under international telecommunications jurisdiction, but is used internally by FAA Technical Operations to identify National Airspace equipment not covered by any other identifying code system. The block beginning with Z identifies United States Air Route Traffic Control Centers.