Jazz Summers, who managed some of Britain's most successful bands including Wham!, Snow Patrol and The Verve, has died, his spokesman has confirmed.
The 71-year-old, who helped shaped the careers of the Scissor Sisters, Badly Drawn Boy and Klaxons, had been battling lung cancer for the last two years.
A spokesman for Big Life Management, which Summers co-founded 29 years ago, said: "The music industry has lost one of its most vibrant, most notorious and most brilliant characters. A champion of new music, a non-conformist and a visionary, Jazz Summers will be greatly missed."
He added that Summers was a "master of artist development" and his ability to recognise the potential of a song had brought him "huge success across several decades".
Summers's artists sold more than 60 million albums and 72 million singles around the world including more than 100 Top 40 hits, Big Life Management said.
His catalogue of artists also included Lisa Stansfield, Soul II Soul, La Roux and London Grammar.
Jazz was born on March 15, 1944 and enrolled in military school aged 12 before joining the army at the age of 15. He served as a radiographer and spent time in Hong Kong and Malaysia.
In 1985, along with with manager Simon Napier-Bell, Jazz helped Wham! break America and become the first western pop group to tour China.
Summers formed his own management company, Big Life, with Tim Parry in 1986. They also ran Big Life Records, which featured hundreds of releases from artists including The Orb, Yazz - Summers's former wife - Coldcut, De La Soul and The Soup Dragons.
Summers was an active campaigner for artists' rights and, as chairman of the Music Managers' Forum (MMF), he was vocal on issues including the extension of copyright.
He also helped set up the Featured Artists' Coalition, which campaigns for the protection of UK performers' and musicians' rights, and Julie's Bicycle, a not-for-profit organisation working on sustainability in the creative industries.
In September 2013 Summers published his autobiography Big Life.
He is survived by his wife Dianna, his daughters Katie, Rio and Georgia, his granddaughters Claire, Lila and Rose and his brother Don.