Open skies

The first two freedoms concern the passage of commercial aircraft through foreign airspace and airports, while the other freedoms are about carrying people, mail and cargo internationally. The first through fifth freedoms are officially enumerated by international treaties, especially the Chicago Convention. Several other freedoms have been added, and although most are not officially recognised under broadly applicable international treaties, they have been agreed to by a number of countries. The lower-numbered freedoms are relatively universal while the higher-numbered ones are rarer and more controversial. Liberal open skies agreements often represent the least restrictive form of air services agreements and may include many if not all freedoms. They are relatively rare, but examples include the recent single aviation markets established in the European Union (European Common Aviation Area), and between Australia and New Zealand.