Goalkeeper David Stockdale has rejected a new deal from Premier League new boys Brighton in favour of a move to Birmingham.
The 31-year-old, who played 45 times for Chris Hughton's side as they clinched promotion to the top flight last term, has signed a three-year contract at St Andrew's, which begins on July 1.
With his Albion contract set to expire on June 30, Stockdale was offered a new contract by the south coast club.
But he has instead opted to join Harry Redknapp's Blues, becoming their first summer signing.
Stockdale joined Brighton from Fulham in 2014, making 139 appearances for the Seagulls.
Brighton boss Hughton thanked Stockdale for his contribution to the club following his departure.
He told Albion's official website: "Firstly, and most importantly, I would like to thank David Stockdale for his immense contribution over the past three seasons.
"He has been the stand-out goalkeeper in the Championship and was a key member of our side as we went so close in 2016 and when we won promotion last season.
"I have a lot of time for David, not just for what he achieved on the pitch here, but also with his contribution to the club, community and particularly around the time of the Shoreham air crash. I wish him all the very best for the future.''