The account, run out of JWT's Atlanta office, will now stay with the agency for the next five years.
JWT, owned by the WPP Group, has been retained by the Marine Corps for more than 50 years, and the future of the account was never thought to be seriously in doubt.
It has won numerous awards for the work it has done for the Marines, as well as helping the body to meet recruitment targets.
In the late 1990s, senior military and navy officials made recruitment and retention their top goal, with army officials creating a marketing strategy group in 2000, after missing recruitment targets in 1998 and 1999.
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