IN A few hours' time Estelle will be performing live on The Late Show With David Letterman. Tomorrow night she'll be recording a session for rival chat show The Late Late Show With Craig Ferguson. At this particular moment, however, she's stuck in traffic in downtown New York on her way to a photo shoot with one of the city's style bibles. After she's thrown some shapes for the camera, she'll be zig-zagging back across the city to do a couple of radio interviews.
The reason Estelle is so in demand right now is because she has just released one of the surprise hits of the year. A duet with American rapper Kanye West, 'American Boy' is a catchy R&B single that has already spent six weeks at No1 in Britain and looks set to repeat the trick in America.
"The radio stations over here can't get enough of it," she says. "The response has been phenomenal. A fortnight ago I was so busy, every day just blurred into the next; now the album has come out, things are even crazier. I honestly don't even sleep any more – I just stay awake and power nap."
To the casual music fan, Estelle might seem like the latest overnight success story. The reality is that the west London rapper has spent the past 10 years developing her craft. She started out freestyling at regular hip hop nights and soon developed a reputation for leaving her fellow MCs dead in the water.
Impressed by her flows, 1extra's DJ Skitz invited her to guest on his album Countryman and within two years she had collaborated with a whole host of underground artists, including Blak Twang and 57th Dynasty. Voted best female artist at the UK Hip Hop Awards three years running, she started her own label, Stellarents, and released a handful of critically acclaimed mix-tapes and 12ins. The single that scooped her a Mobo Award for Best Newcomer in 2004, however, was the radio-friendly '1980'.
"I'm still proud of that track," she says. "It had a great vibe to it and it showed people I could do something that would appeal to the mainstream as much as the underground. Hearing it played on Radio 1 for the first time was dope."
Estelle's self-produced debut album, The 18th Day, failed to replicate the success of the single and she was promptly dropped by the V2 label.
"At the time I was devastated," she admits. "But in retrospect I'm glad because it gave me the incentive to pick myself up, move to Brooklyn and raise my game."
Now signed to John Legend's Homeschool Recordings, Estelle has just released her second album, Shine. Written and recorded in her adopted homeland, it's an uplifting spring/summer album packed with sophisticated soul, R&B, reggae, dancehall and hip hop tracks. As well as the single with West, there are cameos from rapper Kardinal Offishall, Gnarls Barkley singer Cee-Lo and label boss and comrade Legend.
"I had a lot of fun making this album and I really enjoyed working with all the different singers and producers," she says. "I don't know if people will notice but I really felt like I was able to spread my wings with this album and push myself in new directions. It's not just the fact I'm a bit older and wiser, I feel more confident, more relaxed and more driven as a singer, rapper and artist."
If the reviews everywhere from Vibe to Rolling Stone are anything to go by, people have definitely noticed that Estelle has matured as an artist. She has also nurtured her voice so she sings as much as raps on Shine.
"I have to give John credit for that," she says. "He really pushed me to listen to my voice and sing more. Working with him and signing to his label seemed a very natural thing to do because he likes what I do and has faith in me.
"Aside from sharing a passion for all kinds of music from jazz to heavy rock, we're both very motivated and ambitious. We know it takes a lot of hard work to get anywhere in the music industry and we're not afraid to put in that hard work."

On song: Estelle has made a splash by teaming up with Kanye West
In a strange twist of fate, Estelle first met Legend back in 2004 on a visit to Los Angeles. She was walking past Roscoe's Chicken and Waffle House when she spotted Kanye West and asked him if he could introduce her to Legend. West was a little taken aback but still invited her to drop by the studio and the trio have kept in touch ever since. "What can I say about them?" she muses. "They're like family to me. We don't get to hang out as much as we used to but I respect and admire them both as artists and people."
Listening to Estelle wax lyrical about other artists she admires, from Mary J Blige to Jill Scott, it's hard to see how anyone could resist collaborating with her. Aside from her ability to pen catchy hooks and witty lyrics, she seems to have an endless supply of energy, self-determination, good humour and bare cheek. She also has a strong social conscience and plans to use her success to draw attention to issues she feels passionately about. A few days ago she played the opening ceremony of New York's annual Aids Walk and earlier this year she helped the Body Shop raise more than $850,000 for the Staying Alive Foundation. The campaign, promoting a limited edition Guarana Lip Butter, was targeted at the under-25s and publicised on MTV to help raise awareness of HIV and Aids prevention.
"I'm very happy to be working with Staying Alive because encouraging young people to practise safe sex is something I care deeply about," she says. "I can't believe it's 2008 and so many young men and women still aren't prepared to protect themselves and use a condom. My job is to educate them to think about their actions and stop playing Russian roulette with their sexual health."
Estelle has been an ambassador for Virgin Unite since 2004 when she agreed to help the foundation focus on empowering marginalised young people around the world. "It's very irritating that everything in the world comes down to money, so I try to do as much work as I can to support grass roots charities and organisations when I'm on and off the road," she says.
"Most of the time my job just involves talking about their work and letting people know what they're about but I also do things like workshops, Q&A sessions and video messages."
Asked which of her charitable ventures has proved the most rewarding, Estelle falls uncharacteristically silent. Eventually she says: "I've enjoyed all the projects I've worked on but visiting South Africa for the first time is something I'll never forget. I went with Richard Branson and Kelly Holmes to launch Women On The Move and couldn't believe what a beautiful country it was.
"Seeing so much poverty and suffering on a daily basis was very shocking and upsetting, but once you get over the shock you're able to see all the good work people are doing. There are lots of organisations trying to make a difference but the aim of Women On The Move is to radically improve women's lives on a short and long-term basis. They provide college education, HIV and Aids prevention/awareness training and empower young women who have to take care of their families through peer to peer mentoring."
The second of eight children in a large Senegalese/Granadan family, Estelle insists she wouldn't be where she was today if she didn't have the love and support of her mum, aunties and sisters. "Between them they've definitely inspired, encouraged and mentored me. Apart from obvious things like listening to my tracks and coming to my shows, they've always encouraged me to just believe in myself."
The fact that she's riding high in the charts on both sides of the Atlantic must make believing in herself easy right now. "Oh, it is," she laughs. "It is. When John and I first started working on this album he told all his colleagues: 'Just you watch, she's going to be a star.' And now I am!"
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Estelle plays ABC, Glasgow, June 9. The single, No Substitute Love, is released June 30. Shine (Homeschool Recordings) is out now. •
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