Huddersfield have signed Aaron Mooy from Manchester City in a club record deal that could rise up to £10 million.
Huddersfield will pay £8m up front for Mooy, who spent last season on loan at the club and won their Player of the Year award, with City potentially receiving another £2m as part of the deal.
The Australia international has signed a contract with the Premier League newcomers until 2020, with Huddersfield having the option to extend the deal by a further season.
"Huddersfield Town has today completed the permanent signing of reigning Player of the Year Aaron Mooy," a club statement read. "Town has paid a guaranteed record fee of £8m to Manchester City for the Australian international, with additional contingencies that could see the deal rise to £10m."
Mooy, who joined City from Melbourne City in 2016 before joining Huddersfield on loan, was a key figure as the Terriers gained promotion to the Premier League for the first time in their history last season.
"Everybody who has watched our team in our promotion season knows how huge it is to have Aaron back at the club as we enter the Premier League for the first time," Huddersfield head coach David Wagner, who signed a new contract on Friday, said. "I'm sure our fans will be very happy to see him back.
"As I said many times last season, Aaron was right at the heart of our team. When he played well, we usually played well -- and won. His performances for us understandably brought a lot of interest in him this summer, so it is a big statement that Aaron wants to return to us.
"I think he understands that playing so regularly for us at a good level improved his game too and now he has the chance to be a regular in the Premier League; something that is very exciting for every player. He is still a great age and has space to improve, which is exciting for us too.
"His return, along with the early signing of Laurent Depoitre [from Porto], demonstrates the commitment our chairman, and the club, have at becoming a success in this division."