An airline alliance is an agreement between two or more airline

Airline

An airline provides air transport services for traveling passengers and freight. Airlines lease or own their aircraft with which to supply these services and may form partnerships or alliances with other airlines for mutual benefit...

s to cooperate on a substantial level. The three largest passenger alliances are the Star Alliance

Star Alliance

Star Alliance is the world's first and largest airline alliance, headquartered in Frankfurt am Main, Germany . The alliance was founded in 1997 by five of the world's leading airlines: Air Canada, Lufthansa, Scandinavian Airlines, Thai Airways International and United Airlines...

, SkyTeam

SkyTeam

SkyTeam, branded as SKYTEAM, is an airline alliance with its centralised management team, SkyTeam Central, based at the World Trade Center Schiphol Airport on the grounds of Amsterdam Airport Schiphol in Haarlemmermeer, Netherlands...

 and Oneworld

Oneworld

Oneworld , branded as oneworld, is one of the world's three largest global airline alliances with its central management team, oneworld Management Company, based in New York City, New York, USA. Oneworld was founded in 1999 by American Airlines, British Airways, Canadian Airlines, Cathay Pacific...

. Alliances also form between cargo airline

Cargo airline

Cargo airlines are airlines dedicated to the transport of cargo. Some cargo airlines are divisions or subsidiaries of larger passenger airlines.-Logistics:...

s, such as that of WOW Alliance

WOW Alliance

WOW Cargo Alliance is a global cargo alliance between SAS Cargo Group and Singapore Airlines Cargo.WOW is the world's second largest Cargo alliance consisting of only 2 Members and is currently competing with the only other Cargo alliance, SkyTeam Cargo....

, SkyTeam Cargo

SkyTeam Cargo

SkyTeam Cargo is a global cargo alliance in which all members are also members of the SkyTeam airline alliance. SkyTeam Cargo is currently the largest cargo alliance, and is competing with the WOW Alliance.-History:...

 and ANA/UPS Alliance. Alliances provide a network of connectivity and convenience for international passengers and international packages. Alliances also provide convenient marketing branding to facilitate travelers making inter-airline codeshare connections within countries.