The Beauty Spy shares her secrets on designer cosmetics

You won’t see her, but she’s there, in the salons, spas and shops, and she’s happy to share her secrets on designer cosmetics.

Another day, another designer decides to launch a skincare and make-up range. The latest one is Tom Ford, who will add to his existing 12-lipstick collection with a full range of 132 items this month. It will be sold at posh places such as Harvey Nicks, and it looks gorgeous - but, a cynic might ask, does it really work or is it all about image? Of course it is, up to a point, but it is also about producing quality stuff (as well as a nice box).

Possibly the most famous designer label with a well-developed cosmetics range is Chanel, which launched its first Precision line in 1999, 89 years after Coco Chanel opened her first shop. It continues to be at the cutting edge of cosmetics; next week is the launch of its much-hyped nail collection Les Jeans De Chanel, created by Peter Philips, the creative director of Chanel Makeup. This trio of blue nail varnishes (they really look sooo much better than they sound) are inspired by this season's must-have: denim.

Dior is famous for its good foundations, concealers and lipsticks, while YSL has the global best-seller and magic potion touche Éclat (but more on concealers next week). Burberry launched its cosmetics range of 95 products in 2010. With traditional Burberry packaging, the products are dominated by neutral tones and are easy to use. At the time Christopher Bailey, Burberry's chief creative officer, told the Financial Times that he "looked at it as an extension to fashion. I approached it in the same way as I approach designing a dress".

The launch of The Make Up by Dolce&Gabbana in 2009 was hugely successful, unsurprisingly so, as the whole range just screams glamour. Giorgio Armani is another designer who has created a great line of products; who can resist that sultry red lipstick?

But not everyone has done as well. Designers have a tough job convincing women to trust them when it comes to skincare and make-up. A lot of us would prefer to go to a specialist such as MAC or Lancôme. Failures include Versace Make-up, launched in 1998 and discontinued in 2009; Prada Beauty, which closed in 2007 after seven years; and two Calvin Klein collections.

Does the beauty spy suggest you opt for designer make-up? If it makes you feel good, as well as look good, why not?

Personally I find few things in life as exciting as opening one of those little black Chanel boxes. I feel glamorous, pampered and full of optimism, and that's before I've even put the cream on my face. Sadly a tub of Nivea just doesn't have the same effect. At least psychologically. And isn't that all part of the package? Whatever colour it happens to be?

3 of the best

Glamorous cosmetics bags to complement your wardrobe

A LA VOLETTE COSMETICS BAG, DH270 Put other holdalls to shame with this luxurious tapestried make-up bag that has been woven by French craftsmen on a traditional loom. It's a classic.

LULU GUINNESS CAMEO LAMINATE PRINT LARGE T-SEAM COSMETIC BAG, DH198 Famous for her witty handbags, Lulu will turn you into a true glamour girl with this gorgeous cameo print bag. It's the perfect size for travelling and popping in your suitcase, too.

MULBERRY ROSIE ANIMAL-PRINT COSMETICS BAG, DH473 Give your lotions and potions a treat with this funky taupe and purple animal-print cosmetics bag. Who said only the bags on your arm had to be designer?

M loves

EXOTIC EYELASHES Stunningly intricate paper eyelashes by Luna & Curious are a sure way to wow people at parties. Available in five styles, including Peony (pictured) and Peach Blossoms, each pattern depicts a classic Chinese symbol; the peony symbolises happiness. But symbolic meanings aside, these exotic falsies are well worth the price for their sheer glam value.

Luna & Curious Large Peony Paper Eyelashes, Dh72, available online at Culture Label, www.culturelabel.com