MELBOURNE jewellery designer Julia deVille spends up to $300 a month on lingerie and doesn't baulk at paying up to $600 for a matching bra and brief set.

And she is not alone. The 25-year-old is among a growing clique of Australian women who are spending more money than ever before on fashionable underwear. Australia's intimate apparel market is now worth an estimated $600 million annually. The growth, say industry insiders, is being driven by an underwear revolution. Bras and briefs are no longer perceived as a boring functional necessity. These days, they are a fashion statement, even if no one ever sees them.

"Lingerie is one of our strongest growing categories," says Larice Lewis, Target's general manager of merchandise. "And I think it has a lot to do with the fact that underwear is a lot more fashionable these days. Customers don't just want a garment that offers support and comfort and does all the right technical things, they also want garments that are feminine and fashionable."

Jasmine Hickman, of Melbourne lingerie boutique Smitten Kitten, agrees. "I think women's attitudes to lingerie are really changing, particularly in the past year or so. In the past, women would come in and buy a nice lingerie set for a special occasion. Now, I have women coming in to buy beautiful lingerie to wear every day," she says.

"I have clients now who will spend up to $100 a week in here … because they understand that wearing nice underwear not only feels more comfortable and gives them a better shape, they also feel better knowing they have something beautiful on underneath."

"I just love the fabrics and the workmanship," says Ms deVille. "And sometimes I like to wear clothes that will show off a nice bra, so for me it's not just underwear, it's actually part of my outfit. It's a fashion item."

Australian designer Collette Dinnigan — renowned for her use of lacy, silky, diaphanous fabrics with delicate detailing — is the latest in a string of local fashion designers to launch a lingerie collection. Dinnigan's Wild Hearts range, which goes on sale in Target stores on Thursday, is the designer's first lingerie collection to be available in Australia.

"I think women are investing more in their lingerie these days," says Dinnigan. "They know that wearing nice underwear not only makes their clothes on the outside look better, it gives them confidence."

Last year Sydney jeans queens Sass & Bide teamed up with popular bra brand Lovable to create a lingerie line. And local fashion labels Willow, Fleur Wood and Little Joe by Gail Elliott also have lingerie offerings.