Celtic captain Scott Brown has signed a new three-year contract extension, with the club having the option of adding a further 12 months to the deal.
Negotiations had been protracted, with talks stalling over a fee demanded by the 26-year-old midfielder's advisors.
"I'm pleased that this is now all sorted and now I just want to get on with the job in hand," said Brown.
"I'm happy to be back from injury and I now want to just concentrate on the challenges which face us this season."
Brown appeared as a second-half substitute during Wednesday's Europa League defeat by Atletico Madrid, having been out since mid-September with an ankle injury.
And manager Neil Lennon is delighted to have his skipper back in the fold, with his future settled.
"Scott is a crucial member of our squad and someone we felt it was very important to keep at the club," he told the club website.
"He is a special player and his commitment, drive and all-round ability is something we feel is very important to us.
"I'm pleased we've been able to finalise this and I would like to thank Scott's representatives for their assistance in bringing these negotiations to a successful conclusion."
Celtic paid Hibernian £4.4m for Brown in 2007, a fee that remains a record between two Scottish clubs.
Brown has made 27 appearances for Scotland, missing the final Euro 2012 qualifying matches against Liechtenstein and Spain through injury.