West Ham United have signed midfielder James Ward-Prowse from Southampton for a fee thought to be in the region of £30m.
The England international, 28, has joined the Hammers on a four-year deal.
Ward-Prowse joined Southampton at the age of eight and made 410 senior appearances as well as captaining the club, who were relegated to the Championship last season.
“I’m buzzing to be here at West Ham United,” he said.
“From the outside looking in, this is a club that has been on the rise for a number of years now and coming off the success in the Europa Conference League last year, you can feel there is real momentum around this club.”
West Ham manager David Moyes said: “He’s performed to a very high level in the Premier League over the last decade, constantly producing good numbers season after season.
“His leadership qualities are obviously another huge plus for us – he’ll be a big voice for us, someone who drives the team on from the middle of the pitch.”
Ward-Prowse made his Saints debut as a 16-year-old in an EFL Cup tie against Crystal Palace in October 2011, while making his top-flight bow on the opening day of the 2012-13 season.
Renowned for his set-piece delivery, only David Beckham has scored more than Ward-Prowse’s 17 goals from direct free-kicks in the Premier League.
Southampton said Ward-Prowse, who was appointed club captain in 2020, is “one of the finest talents to ever come out of the Saints academy”.
A statement read: “His commitment to Southampton FC over two decades, his professionalism both on and off the pitch, and his support in the community means he leaves with his legacy as a Saints legend well and truly cemented.”
West Ham, who sold England midfielder Declan Rice to Arsenal for £105m, have been trying to sign Ward-Prowse for much of the summer.
His arrival follows Mexico midfielder Edson Alvarez joining the Hammers from Ajax in a deal thought to be worth about £35m.
West Ham have also agreed a deal for Manchester United defender Harry Maguire, while they are interested in signing Cole Palmer on loan from Manchester City.