ICM Partners will represent Joss Stone worldwide following a new deal.
The singer was previously represented by the agency's concerts division for North and South America only.
The expanded relationship comes as Stone gears up to release new material.
Her first single in three years, Walk With Me, was released recently, while her Dave Stewart-produced, eighth album is due out in the autumn.
Stone has also launched a podcast called A Cuppa Happy and is lending her voice to an animated forthcoming film Paper Birds Pt. 2 which stars Edward Norton.