Mike Lee, the PR executive who helped London's winning bid for the 2012 Olympics, has died after suffering a heart attack at the age of 61.
Lee also worked on Rio's successful bid to host the 2016 Games, as well as helping Qatar secure hosting rights for the 2022 football World Cup.
He was also director of communications and public affairs for Uefa and media and political strategist for the Premier League.
In 2006 he founded Vero Communications.
Its current director John Zerafa described Lee as "always inspiring, challenging and innovative".
A statement added: "He leaves an indelible legacy in the world of sport. He will be deeply missed by all those who have worked with him, and been advised by him."