Burnley have completed the signing of Derby defender Jason Shackell for an undisclosed fee.
The Clarets have been pursuing Shackell for some time and had an improved bid for the centre-half accepted by their npower Championship rivals on Wednesday.
"Jason has always been 100% professional and a fantastic player to work with," said Derby boss Nigel Clough. "He played in every minute of every game last season, so it came to no great shock when other clubs registered their interest in him."
The 28-year-old, who was an ever present for the Rams last season and captained Derby in the absence of defensive partner Shaun Barker, has signed a four-year deal at Turf Moor.
"Although I am sad to see Jason leave, we have Jake Buxton, Tom Naylor and Mark O'Brien, who have all proved to be more than capable at performing in the npower Championship. We are also actively looking to bring in another central defender, and hope to make an announcement in the not too distant future," Clough added.
"I'm sure that I speak for everybody at the club when I wish Jason the very best for his future career at Burnley - just as long as they finish below us in the table."