Celtic have confirmed the signing of Jonny Hayes from Aberdeen for an undisclosed fee, thought to be in the region of £1.3 million.
The winger has signed a three-year contract.
Ryan Christie will move in the opposite direction, with the Celtic attacker joining Aberdeen on a season-long loan deal.
Hayes, 29, signed a new contract with Aberdeen last season but has been lured to Glasgow by Brendan Rodgers.
The pair worked together previously at Reading.
Hayes posted a message on the Aberdeen website thanking the club, management team Derek McInnes and Tony Docherty and the fans for their support during his time at Pittodrie.
“Thank you, to everyone from top to bottom at AFC,” he wrote. “From the minute I signed, myself and my family were made to feel so welcome, not just within the club but the whole city. It’s a place that I’ll always hold in the highest regard- off the field my son was born there, but there’s a fair few on the field memories that are not far behind!
“I’m where I am today as a player and person due to the support I received at Aberdeen Football Club and the guidance of the Gaffer and Doc. I’ll never forget it as it can’t be reciprocated! All the best!”
The Irishman was the only non-Celtic player to feature on the Scottish Professional Footballers’ Association player of the year shortlist. He will now vie with James Forrest and Scott Sinclair for one of the wide attacking roles in the Celtic team.
“I’m delighted,” Hayes told celticfc.net. “It’s been in the pipeline for a little while now but I’m pleased to finally get here. I was eager to get it over the line for the last few weeks.
“Celtic have done well over the last few seasons and with the manager coming in last year he raised the level again. It was hard last year seeing all the celebrations and all the stuff on social media and you want that for yourself and to be part of it.
“Now it’s my chance and hopefully, going forward, I can create my own little bit of history and take the chance I’ve been given.”
Hayes admits the prospect of playing Champions League football was one of the big attractions of moving to the Glasgow giants.
“You can’t get away from the Champions League,” he said.
“I can imagine it is the reason many players have wanted to come here. Not only is it the size and stature of the club, Champions League nights and the atmosphere are a massive factor in wanting to come here.
“Whether you’re a football fan or not, everybody knows about the atmosphere of Champions League nights at Celtic Park. I’d be lying if I said I didn’t want a part of that.”