There was a moment recently when Robbie Williams graduated from being merely and infamous former teen star with a successful solo and a brace of hit singles under his belt into a genuine bona fide pop icon. You can pin-point the actual instant the nation took him conclusively to their hearts because it happened at this year's Glastonbury festival in front of the biggest Pyramid stage ever assembled.

And as Robbie launched into 'Let Me Entertain You' he managed to unite the most disparate of audience with one rather old fashioned conceit: classic pop showmanship. It was here (ironically at this very site in 1995 that marked both the symbolic end to his tumultuous tenure with Take That and the kick-start to his solo career) that Robbie proved himself to be this country's supreme pop performer.

Finally, publicly, Robbie had managed to lay to rest his turbulent rollercoaster past. Take That, booze, drugs, rehab, celebrity shags and a catalogue of lurid tabloid headlines - Robbie made all this irrelevant by displaying a deeper understanding of the pure adrenaline rush that only the most brilliant pop music can produce - of course, Robbie says that he's known all along that he had it in himself to be a world class performer. It just took a while for the rest of us to catch up.

"I'm an old fashioned entertainer," he says. " There's nobody else around like me. And I'm serious when I say let me entertain you - I'm not joking - let me do it - and I guarantee you'll have a fantastic time."

Of course, it could all have been so different. After all, you can count on the fingers of one hand the number of teen pop stars who have successfully re-invented themselves as major league, mainstream performers. It would have been all too easy after Take That's messy demise for Robbie to turn into this generation's Andrew Ridgeley. And for a while it looked like he might.

"In the past I've made it hard for people to take me and my music seriously," Robbie admits. "I'd been cocooned for so long that when I was finally released I didn't have a clue what I was doing. I was very young and very stupid and it was inevitable that I was going to fall on the wrong side of the tracks."

There had been hints all along of course that Robbie would end up on top. He was always the most interesting one in Take That, and 'Freedom', his post Take That single had sold more than a quarter of a million copies.

More than a year later his debut solo album, 'Life thru a Lens' (released in September '97) became the sleeper hit of the year. Over coming its slow start (it didn't actually reach No. 1 for 28 weeks) it has almost reached quadruple platinum status and continues to sell strongly. The turning point was 'Angels', the single which tipped the album from respectable into stratospheric sales.

"Last year I'd had two number two singles, a top 10 and a top 20," Robbie recalls. " The album had sold about 33,000 copies - which is bugger all as far as I'm concerned. Then 'Angels' come out and suddenly the album goes from 33000 to 300,000 sales. Then two weeks later it went double platinum. I was a very happy boy!"

An ecstatically-received, sell-out British tour confirmed Robbie's burgeoning popularity. The icing on the cake was the massive success of the album's last single, and Robbie's theme song, 'Let Me Entertain You.' Cue mass adulation, critical aclaim, awards and immense record sales.

All he had to do next was do it all again.