Bournemouth will secure the services of Nathan Ake from Chelsea for £20m, according to Sky sources.
The Cherries have faced competition from other clubs, such as Leicester City and Southampton, who have been interested in signing the 22-year-old defender.
But it is understood the Cherries have won the race.
Ake spent the first half of last season on loan at Bournemouth before being recalled to Stamford Bridge in January.
Bournemouth made a bid to sign Ake at the end of the January transfer window but were rebuffed by Chelsea.
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Cherries boss Eddie Howe said at the time: “We had discussions with Chelsea. The bid that has been reported in the media was miles off the mark.
“We made an enquiry about the opportunity of bringing him back on loan or on a permanent deal, but that was declined.”
Ake, who made his international debut for Holland against Morocco in March, has previously been on loan with Watford and Reading.