Anna Sharapova, tennis star and model: ''I swear by regular exfoliation to keep my skin smooth and glowing and to stay really healthy I have at least eight hours sleep, drink plenty of water and follow a well-balanced diet that is rich in carbohydrates and protein. My three unbreakable rules to keep me looking my best? Plenty of sleep, lots of yoga and playing tennis in the fresh air. And of course I swear by Palmolive deodorants which keep my skin soft but give me total confidence when I'm playing.''
Carolyn Murphy, supermodel: ''My mother always said I should take Omega 3 tablets and she looks fantastic now, with completely flawless skin, so I took her advice. They aren't very glamorous but they are full of essential fatty acids and nutrients. I also take calcium and magnesium tablets to keep my skin really healthy. But if there is one product I can't live without it is Estée Lauder's Advanced Night Repair. It really invigorates your skin overnight. I also drink pints and pints of water.''
Supermodel Cindy Crawford: ''I wish I could say I relied on one of the old wives' tales to look good. But I don't use raw eggs in my hair or cucumbers on my eyes or anything nearly as interesting. I'm afraid it's just the good, old-fashioned tactics. I sleep a lot, drink lots of water, avoid alcohol and cigarettes, eat healthily and do plenty of exercise. It's all remarkably boring, but it's all true. If you just live the perfect life for one week you feel - and see - the benefits immediately.''
Supermodel Elle Macpherson: ''One of the most important secrets of looking your best is to get the right hair colour. The tone of your highlights can really make a difference to your skin tone. Josh at Real, in Chelsea, does my hair. My other trade tips are that you need lots of water and lots of laughter: you should nourish the inside as much as the outside.''
Real, 6-8 Cale Street, SW3. 020 7589 0877.
Supermodel Erin O'Connor: ''If I'm ever feeling low, red lipstick is the best pick-me-up ever. It makes you feel on top of the world. I read somewhere that it's really good for you to have a pint of water before bed every night and first thing in the morning, so I try to do that every day. It gets easier once you get used to it and it must be good for the skin. If in doubt, pile on masses of moisturiser before going to sleep - you feel horrible and sticky but it looks great the next day.''
Supermodel Helena Christensen: ''I feel at my best when I avoid alcohol and smoking and generally party as little as possible. I try to get to bed early as often as I can and I try to only eat vegetables. Clean living is really the only way to look good - which makes it pretty hard work. When I do lapse - because you can't be good all the time - I just drink plenty of water and take exercise to get myself back in shape. It's nothing you haven't heard before but discipline is the only thing I can rely on to look my best.''
Supermodel Jacquetta Wheeler: ''Sleep is always my top beauty tip. I look and feel so much better after a couple of early nights - preferably with a bit of pampering thrown in. I swear by Dr Hauschka products if I've had a few late nights. The exfoliating mask is brilliant for making your skin really glowing and soft. I always try to use it before a shoot - it makes me feel really new.''
Her boyfriend, Mario Testino's assistant Alexi Lubromirski, will hear none of it, however. ''She always looks gorgeous,'' he says. ''She doesn't need any help.''
Supermodel Jade Parfitt: ''I always try to drink green tea before I go out partying. I know it's warped logic, but I'm convinced it prepares your body to flush out all the bad toxins the following morning. I also take a multi-vitamin every night before I go to sleep, no matter what I've been doing. I've done it for years and I really believe it does me good.''
Supermodel Jasmine Guinness: ''I really, really love YSL lipsticks. They give the best, thickest slick of colour ever and it makes me want to kiss everybody! I use YSL Touch Eclat everyday too and I love Rimmel Eye and Lip Ink Pots. They last for hours and they come in lovely colours for daytime or evening. My secret potion is a South American face oil called Rose Moscketa. It's wonderful because you can use it as a night cream but it's also brilliant on cuts and bruises. You can find it in most good health food shops.''
Karen Elson, supermodel: ''My hair is not naturally red, it's more of a mousy strawberry blonde. I first dyed it when I was 16. I wanted it to be bright red but it came out like Ziggy Stardust. I washed it about 20 times but it wouldn't come out and I had to go to school with it. I often still dye it myself using Clairol hair dye [try Nice'n Easy in Light Auburn, £4.30]. Berocca vitamin tablets get me through the early mornings and long schedules of the shows and Crème de la Mer , is the only moisturiser that soothes and doesn't irritate my skin. It's especially great after the shows, when I've had make-up applied and removed 10 times a day.''
Leah Wood, model and singer: ''I don't have any real secret potion that I stick to. I love trying out new products and I love having a proper pampering night in, with cucumber slices on my eyes - the works. If you can take time out to really relax - exfoliate, moisturise and lie in a gorgeous-smelling bath with plenty of scented candles - you always feel like a goddess the next day.''
Liberty Ross, supermodel: ''I never go anywhere without my Dior Maximeyes mascara and my Dior Addict perfume. Other beauty essentials I always have are the Shu Uemura cleanser and the Never a Dull Moment exfoliator from Origins. I'm obsessed with skin and really try to look after mine well, so I love trying out new products. But the main thing is to have lots and lots of sleep. I am really strict about drinking gallons of water and I eat healthily too - but I eat a lot. Dieting isn't for me at all - it would make me ill. The most important thing to stay beautiful is to lead a healthy lifestyle - it's really basic but it's true.''
Supermodel Lily Cole: ''I know I should have cultivated a few beauty secrets by now but I have so much stuff plastered all over my skin all the time I just hope it turns out alright when I wash it off. I'm always being told to get lots of sleep, take all my make-up off before bed and drink lots of water but I don't manage to stick to the rules all the time. When I'm at home I use Dermalogica products on my face. That seems to work.''