From July 2012, Droga5 will take over lead creative duties for the airline from incumbent Publicis Mojo and assume media buying responsibilities in key offshore markets.
ZenithOptimedia has retained the global media account, seeing off competition from OMD and MediaCom, after a process that lasted 10 months.
Droga5 will lead the account out of its Australia office, but also work with the agency's senior team, including David Droga, in New York.
The airline also will collaborate with: Publicis' Amnesia Razorfish for digital media strategy; R/GA for specialist digital projects; and Publicis Mojo, which will continue to work as a strategic advisor, the company said.
In Australia, Qantas also appointed Subnine to support sports sponsorships and Play Communication to support a range of arts and entertainment properties, according to a press release.
The roster will commence in the new financial year.
David Nobay, creative chairman of Droga5 Australia, said: "It has been our ambition to partner with the most progressive and influential brands in the country since we opened our doors in Australia four years ago.
"Being chosen by Qantas to help them evolve their marketing at such a pivotal moment in their company's history is an enormous privilege."
David Droga, founder and creative chairman of Droga5, described Qantas as Australia's "most iconic global brand".
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