Celtic’s chief executive is to step down from the role in the summer after 17 years at the club.
Peter Lawwell will retire in June after first joining the club in 2003.
He will be succeeded by Scottish Rugby’s chief operating officer Dominic McKay.
Celtic have so far won 29 trophies during Lawwell’s tenure, including 13 league titles, four domestic trebles and participation in the last 16 of the Champions League on three occasions.
Mr Lawwell said: “It has been an enormous privilege to have served the club and our supporters for more than 17 years – a wonderful honour to have been part of an institution I have loved and supported all my life.
“I will always be very proud of what we have achieved together and it has been a particular privilege to be involved throughout a period in the club’s history which has brought immense domestic success – as well as so many great European nights at Celtic Park.
“Everything we have aimed for and achieved has been for everyone associated with the club. I have greatly valued my involvement with Celtic supporters in Scotland and around the world.
“Celtic’s reputation is built on three pillars – success on the field of play, sound business management, and a real and sincere charitable ethos, building on the club’s founding traditions.”
His final season – which started with Celtic chasing a record tenth consecutive title – looks set to end in disappointment, with the club currently 23 points behind Rangers.
But Lawwell said: “Celtic will always be the biggest and the best club in Scotland and our supporters will always be everything to our success. We need our fans with us to achieve that success.”
Mr McKay will take up the role in the summer after spending 13 years at Scottish Rugby in a variety of roles, most recently as chief operating officer.
McKay said: “Joining Celtic FC as chief executive is a once in a lifetime opportunity and a new challenge I am very excited about taking on later this year.
“I have been incredibly impressed with the vision and people within the club and I look forward to working with them.”
Lawwell has come under increasing criticism this season from fans with the nine-in-a-row champions failing to keep pace with league leaders Rangers and being knocked out of Europe and the League Cup.
There was also a huge furore over the club’s decision to take the squad to Dubai for a mid-season training camp with Lawwell admitting it had been “a mistake”.
Celtic chairman Ian Bankier said: “On behalf of the Celtic board of directors, I would like to thank Peter for his monumental contribution to Celtic and its success during the past 17 years.
“Peter has given his life to our cause during his term of office, delivering a period of unprecedented success to the club on and off the field. He will be regarded as a man who has played a pivotal role in our history and we should always respect the huge impact he has had on the club.
“It is, of course, with great sadness that we have accepted his decision to leave the club but we understand and appreciate that he considers now is the right time for him to leave and we have been succession planning for this day for some time.
“Peter’s expertise, intelligence and judgement has guided Celtic brilliantly through the past 17 years and as a chairman, I could not have hoped to work with a more able and skilful chief executive – someone with Celtic in his soul, who has had the club’s best interests at the heart of every decision he has made.
“With Peter’s departure, we must also recognise the huge role he has played in promoting Celtic’s interests at a European football level, particularly through his positions on the European Club Association Board and the most senior UEFA committees.
“He was elected to these posts entirely on merit, and his work and efforts in this area have been of great benefit, both to Celtic and Scottish football in general.
“I wish Peter and his family nothing but the very best for the future.”