U2, who have won eight prestigious Grammy Awards in the last two years, are stubbornly clinging to their status as one of the biggest bands in the world.
The most popular groups in the history of rock all have several things in common.
U2 have sold more than 125 million albums around the world
The music must be inspired and appeal across generations and be distinctive, if not always groundbreaking.
But such success is down to more than music. They have to be compelling performers, charismatic and intelligent enough to make good decisions and keep their feet on the ground.
They also have to want it. They have to want to be the biggest band ever and not stop wanting it.
The Beatles had it, the Rolling Stones still have it, REM hold onto it and Queen were it in a catsuit. And U2 have it in spades, and keep churning it out.
Their latest album, How To Dismantle An Atomic Bomb, came 28 years after the schoolfriends got together in Dublin and 17 years after The Joshua Tree cemented their place on the all-time rock A-list.
They may have lost some of the edginess and raw, youthful force that propelled them to the top, but they have lost none of the desire or ability to craft songs and albums.
Vertigo, the first single from the new album, went straight into the UK singles chart at number one, knocking Eminem off the top spot and giving them their 26th top 10 hit.
"The challenge is to be bigger and bolder and better - to make records the whole world will listen to," Bono recently said.
Drummer Larry Mullen Jr echoed those sentiments: "We're very competitive - we want to be on the radio, have big singles. We don't want to be thought of as a veteran band."
The band have done "everything in their considerable powers" to ensure they remain the biggest band in the world, according to Q magazine editor Paul Rees.
"This makes them hugely determined and formidable."
He added: "They are equally determined to push themselves to make music that continues to stand up.
"As such, they've constantly re-invented and challenged themselves. They are, perhaps, alone as the only rock band that has got better with age."
The other key ingredient was the fact they were highly organised, Mr Rees said. "They do everything in the right way."
The group were born when Mullen put an appeal for bandmates on a high school notice board, attracting fellow pupils Paul Hewson (Bono, vocals), Adam Clayton (bass), David Evans (The Edge, guitar) and his brother Dick.
Dick Evans soon dropped out and the four-piece were known as The Feedback and The Hype before settling on U2.
By 1978, they had won a talent contest and got noticed by a manager, Paul McGuinness.
U2'S GREATEST HITS
Pride (In The Name Of Love) - 1984
With Or Without You - 1987
I Still Haven't Found What I'm Looking For - 1987
One - 1992
Discotheque - 1997
Beautiful Day - 2000
Vertigo - 2004
"They were brilliant, but very coarse," McGuinness recently said. "In a way, they were doing exactly what they do now. Only badly."
They struggled to attract record company attention, later being described as "pretty damn average" and "strange and eerie" by scouts who saw them live.
They released two Ireland-only singles, which topped the national charts in 1979 and 1980, leading to a deal with Island and their debut album Boy.
The stadium-filling, anthemic sound was U2's aim from the start, and their third album, War, saw them make the breakthrough on both sides of the Atlantic, going to number one in the UK and 12 in the US.
Songs like Sunday Bloody Sunday and New Year's Day brought success and an image as a political and spiritual band - which Bono rejected as a cliche.
His stage performances - which included flag-waving, speaker-climbing and drum-throwing - earned him a reputation as an electric performer, and their appearance at 1985's Live Aid is widely seen as sealing their global stardom.
In 1987, The Joshua Tree broke sales records and saw the band reach the height of their powers with hits including Where the Streets Have No Name, I Still Haven't Found What I'm Looking For and With Or Without You.
Bono had become a strident campaigner on global issues
Those songs took the band's epic, atmospheric sound to a simple, powerful and popular pinnacle.
The end of the decade marked a crucial point for the band - they had reached the top but still yearned for new challenges and achievements.
These came in the form of explorations of different branches of rock and forays into electronic dance music, plus wildly extravagant stage shows, while still trying to retain their mass appeal.
The Achtung Baby album in 1991 was followed by Zooropa, Pop and their corresponding stadium tours, which featured giant olives, flying cars, live phone calls to the White House and Bono's transformation into alter-egos The Fly and MacPhisto.
He was also building a parallel reputation - not always to the pleasure of his bandmates - as a campaigner on issues from global debt to Aids.
Before the release of How To Dismantle An Atomic Bomb, they had sold 125 million albums around the world. But they still want more.