It is a mark of Tutu's success as a thought-provoking, even challenging, exhibition, if not necessarily as an exhibition of ballet garments, that it is so much more than the sum of its eclectic parts.

It would be hard to imagine a less interesting way to display the 12 interpretations of the tutu on show. It's static - ironic, given that the accompanying brochure, available only by trekking downstairs to the shop, describes the Australian Ballet as "art that moves" - on headless, armless white mannequins, behind glass in a small, dimly-lit, windowless room. In the entrance there is an accompanying statement and in one corner, a video plays in front of an uncomfortable bench. That's it - no other supporting materials, no ballet-related displays, not even the accessories created to accompany the tutus and worn with them on the video.

That despite such uninspiring curating they raise fascinating and significant questions about the nature of costume and the relationship between form and function is a tribute to the originator of this interesting concept - an unnamed person in the Australian Ballet which, in 2002, invited 17 Australian designers to design and construct their interpretation of a tutu.

It is also, of course, a tribute to the designers who took part, drawing as they have from inspirations ranging from the floating airiness of the dandelion (Dinosaur Designs) to raindrops on emu feathers (Balarinji).

Eight of the tutus on show here are among those created by the designers for the Tutu Project. Their brief: simply the definition of a tutu as a ballet dancer's short, projecting skirt.

As well, the exhibition includes some of the more innovative tutus produced for actual Australian Ballet productions - for instance the imaginative creation by costumer designer Stephen Galloway for The Vertiginous Thrill of Exactitude in 2000. Galloway thumbed his nose at the traditional notion of a skirt, creating instead a stretch nylon fabric-covered disc reminiscent of a flying saucer, entirely in keeping with the work. On stage in that production that looked devilishly uncomfortable, but wonderfully effective.

And there's the rub. If a ballet costume is never actually worn in a ballet, if no dancer has ever danced in it, if it may be physically impossible, or at least very difficult, for a dancer to do so, at what point does it cease being a costume for a ballet dancer and become simply a costume inspired by the notion of a tutu? And does it matter that we cannot know whether these tutus would actually serve their purpose?

The accompanying statement displayed at the exhibition entrance states that the tutu, which evokes romantic images and is imbued with quasi-magical qualities, has to be not only visually commanding but a practical, functional working costume.

Are these visually commanding? Absolutely. Are they practical and functional? It's impossible to know.

No answers are provided by the extremely brief video which plays, somewhat predictably, to the accompaniment of Tchaikovsky's Swan Lake . In a matter of minutes the tutus flash by, modelled on a catwalk, with some gentle gyrations but very little dancing, the models generally in high heels rather than ballet shoes.

The statement concludes that each tutu has its own history, that its seams and darts offer clues to its life on stage and relationship to the body.

But only one tutu here offers such clues: the opening exhibit, the beautiful and arresting creation by the late costumer designer Tom Lingwood produced for The Australian Ballet's Odette in 1977. This is a classic tutu - pieced bodice, white tulle skirt, sequins, real and fabric appliqué feathers. We can visualise that pirouetting dancer, that swan, in a way that's just not possible with the others on show here. And that is not simply the conservative interpretion that here, in white tulle, is a "real" tutu. It's because this tutu and only this tutu speaks to us of the dancers who have worn it, it has a mended and slightly battered air, testament to its relationship with the women's bodies which have given it life.

To suggest that the concept of a tutu cannot, ultimately, be separated from its purpose is not to denigrate the fashion designer's creations, nor even to suggest they did not have in mind that they were intended for a dancer.

Several of the pieces here are simply exquisite. Collette Dinnigan's beaded black lace confection, inspired by the ballet dancers of Edgar Degas, is a masterpiece of tailoring, its skirt overlaid with fine, beaded black lace, its bodice richly beaded and sequinned.

Richard Tyler's somewhat unimaginative fluffy white confection is, nonetheless, superbly made, its classical skirt topped by large, tulle cabbage roses on the hips, two more on the left shoulder of its its finely tucked bodice. It pays homage both to his own work and to his mother, a former Australian ballet seamstress.

Others are nothing less than wearable art. For the Scanlan and Theodore label Gary Scanlan created a skirt entirely composed of two layers of black ballet shoes, each shoe inscribed with a dancer's name. An entertaining creation, it attracted the most attention, but his inspirations were serious: a tribute to the dancers and a nod to the surprise of early settlers who discovered, in this land Down Under, black swan.

Australia, and more particularly Australian wildlife and Aboriginal tradition were the inspiration for indigenous label Balarinji. The starting point for their Emu Dreaming tutu was a traditional black bodice and skirt. But their concentric circular sequinned appliqués depict bush campsites, while the sequinned feather overskirt on one side was inspired by the strutting emu, the raindrops glistening in his feathers.

Fashion designer-turned costume designer Vanessa Leyonhjelm used 15 metres of air conditioning filter mesh to create the ruffled skirt, elegantly edged in red leather and topped by a foam moulded bodice, which she created for the ballet's Divergence in 1994. It looks lights as air - though I recall the dancers at the time complaining that it was anything but. On stage these tutus were a triumph.

Several of the tutu were subversions of the traditional white skirt - Akira Isogawa attached a tail-like bustle of fine, pleated fabric to a singlet and briefs, a studded, wide brown leather belt the unity between the two, while Angus Strathie inverted the tutu to have it stand straight up for his glow worm costume for Wild Swans last year. Rising young fashion star Toni Maticevski, inspired by Swan Lake , created an uninspired mini-poncho of large white silk ruffles, to be worn with similarly ruffled briefs.

One of the edgiest and most successful tutu, the only one on show for a male dancer, was created by jewellery and homewares label Dinosaur Designs, using their trademark resin and plastic. This highly imaginative design, about as far as you can get from oceans of white tulle, was inspired both by the notion of the dancer flying and by the floating airiness of dandelions. Silver wires protruded from standard white briefs, and on the ends of the wires, a series of multicoloured discs of varying sizes. Around the mannequin's neck hung a multi-strand necklace of large, oval turquoise beads.

Up close this looked intriguing though somewhat bizarre. So why successful? Because on the video the male dancer wearing this really danced. And around him, floating on the air like clouds of dandelions, those coloured discs shimmered through the air. Here were those quasi-magical qualities. Here there was truly a relationship between body and costume, a visually commanding, but practical working outfit. A tutu.