James McClean has officially joined Stoke City from second-tier rivals West Bromwich Albion on a deal that will run through until 2022.
The Potters have spent an initial £5m to sign the Republic of Ireland winger, which could rise by a further £1m with add-ons.
Speaking to the club's official website, City boss Gary Rowett said: "James is a player I've admired for a long time. He has real quality with his left foot and he's an old fashioned winger in so much that he retains width and gives teams balance.
"I've spoken to lads who have played with him before, the likes of Darren Fletcher, and they have all said that he's a great guy to have around the dressing room and he's really, really popular with his teammates."
Chief executive Tony Scholes added: "Gary indicated very early on in our discussions over transfers that James was a player he wanted to bring to the Club and we're pleased to have added a player of genuine quality to our squad."
McClean has made over 350 senior appearances during a career that has seen him represent Sunderland, Wigan Athletic and West Brom in England, as well as Irish sides Institute and Derry City.