The regulation of "flight companies" (airlines) is a multi-layered system involving national, regional, and international bodies. In the United States, the primary regulator is the Federal Aviation Administration (FAA), which oversees all aspects of safety, including aircraft maintenance, pilot certification, and air traffic control. Economic and consumer protection issues—such as refunds, "bumping" rules, and advertising—are regulated by the U.S. Department of Transportation (DOT). Internationally, the International Civil Aviation Organization (ICAO), an agency of the United Nations, sets global standards and recommended practices to ensure that "a flight in Japan is as safe as a flight in Brazil." Additionally, the International Air Transport Association (IATA) is a trade association that represents the airlines themselves and helps set industry standards for ticketing and baggage. In Europe, the European Union Aviation Safety Agency (EASA) performs a similar role to the FAA, while individual national authorities (like the UK's CAA) manage local skies. These organizations work together in a strict web of oversight to ensure that aviation remains the safest mode of transport in the world.