Crystal Palace have signed Cheick Doucoure from Lens on a five-year deal for an undisclosed fee.
The midfielder, 22, joined Lens in 2018 and helped the French club win promotion back to Ligue 1 in 2019-20 after five seasons in the second tier.
Doucoure, who has five caps for Mali, said he felt "joy and a lot of pride" to have joined Patrick Vieira's side.
He is Palace's third summer signing, alongside striker Malcolm Ebiowei, 18, and England goalkeeper Sam Johnstone.
Doucoure made 34 appearances for Lens last season as they finished seventh in the table.