The Next Big Thing celebrates its fourth birthday this week. Inevitably, demand will be high, the venue will be rammed and the queues will be hectic in the extreme.

While most clubbers are tucked up in bed dreaming of the weekend, hundreds of others make their way down to the Hanover Grand for a night of revelry.

There are many successful Wednesday night clubs in London but on a Thursday?... it couldn't be done. "When we started the night, people said that there wasn't a market for Thursday-night clubbing," explains TNBT promoter Roger Michael. "In the first two years we had considerable competition from Cafe de Paris, Browns and Emporium but we've seen them all off."

There are many gigs which enjoy notoriety in London, but, more so than any other club, TNBT has been instrumental in forging the capital's famed vibe.

The last three years have seen a marked movement away from dark, dank warehouses and dress-to-sweat raves. Modern clubbers are spoilt for choice with regard to venues and musical preference. The most successful clubs of the recent past realise that the creation of a strong social atmosphere is just as important as the music.

"In the past, you had to use a `name' DJ and he would bring in the crowds," says Michael. "Now, people are returning to a social vibe. There are many components that make a night successful but the people are the club and I try to base the night on that."

The music at TNBT fuses uplifting rhythms and dancefloor anthems in the main room, with R'n'B flavas and rare grooves in the basement.

While patrons sport designer gear, you're just as likely to see funky urban fashions. The night maintains a strong aspirational attraction (Ian Wright, Elle MacPherson, Mariah Carey, Jason Kay and Bruce Willis are just a few of the visiting celebrities) while remaining unpretentious.

"The night is made on the door, so we try to make sure we have the right sort of people. We're looking for a certain attitude when people come to the club. You don't have to be wearing a designer suit and you can get in with baggy trousers and trainers.

"We also get city people here and ask them to take off their ties to loosen up a bit. We want a mixture of different people and styles and try to strike the right balance."

TNBT is also famous for attracting scores of models. Is this also a deliberate strategy? "People come back because of the special atmosphere, but it's a well-known formula that wherever there are beautiful females, men - and other women - also arrive," he admits, with a smile.

With the success of their recent London club tour, TNBT has become a clubbing brand name in its own right and its birthday bash is the event of the month.

Don't despair if you can't get a ticket for the birthday party: you can always catch The Next Big Thing at future dates in Amsterdam, Ibiza, Paris and New York.

TNBT Fourth Birthday Party, Hanover Grand, 6 Hanover St, W1 (0171-499 7977) Thur 10.30pm-4am pounds 12