John Alexander is leaving Tottenham for Manchester United.
Spurs secretary Alexander will take up the same position at Manchester United when Ken Ramsden retires at the end of the season.
He will become only United's fifth post-war secretary when Ramsden ends his three-year tenure in May.
Alexander said: "I am honoured to be offered the chance to be the secretary at the world's biggest football club. I have a series of very hard acts to follow but I am looking forward to working with (manager) Sir Alex (Ferguson), (chief executive) David Gill and the team."
Gill added: "John is the perfect candidate to succeed Ken. He is a real football man with a wealth of experience in the game."