Star Alliance is the world's first global airline alliance. Founded on 14 May 1997, it is headquartered on the grounds of Frankfurt Airport in Frankfurt, Germany, with a subsidiary management company in Singapore. Star Alliance is also the world's largest airline alliance by market share as of April 2024, with 17.4% of the market share, compared to 13.7% of SkyTeam and 11.9% of Oneworld.

An airline alliance is an aviation industry arrangement between two or more airlines agreeing to cooperate on a substantial level. Alliances may provide marketing branding to facilitate travelers making inter-airline codeshare connections within countries. This branding may involve unified aircraft liveries of member aircraft.