Scott Parker has signed a five-year contract for West Ham in a £7 million transfer, the London club said on Wednesday.
The 26-year-old Parker, the first summer signing for the East London club, left Newcastle United to link up with Alan Curbishley, his former manager at Charlton.
Curbishley said: "I'm delighted Scott has agreed to sign for us. Our relationship goes back some time to when he first joined Charlton as a schoolboy.
"He's coming to the club knowing full well that we're trying to push forward and he wants to be part of that. Firstly he wants to improve our team, then he wants to improve his chances of forcing his way back into the England scene."
"He has been captain of Newcastle over the last couple of seasons and he is exactly the type of player that I wanted to bring to the club.
"He's very experienced but still young and I'm sure he's going to be a big asset to West Ham."