Transparency was all the rage in the Italian fashion capital last week, and hardly any of the models wore underwear, either. Susie Rushton got an eyeful of 'peekaboo' chic

The easily embarrassed should look away now - because for the spring/summer 2008 season, Milan Fashion Week wasn't wearing any underwear. The biggest overall trend of the event was for transparent clothes, you see, but rather than also proposing what we should wear underneath such filmy garments, almost every designer left their models baring their chests to an audience who politely pretended not to notice. But, as one respected fashion commentator put it, will real women really be standing in front of a mirror next spring and musing: "How do my nipples look in this?"

The problem is that, in Milan, sexiness is valued above all else. With few exceptions, not revealing the female body in an overt way is simply not an option for designers here. But the tight, short look has dominated fashion for the past two seasons. Change was in the air. So the new silhouette is, by contrast, loose-flowing, billowing and often grazing the ground, particularly for evening wear. The logic goes that, in order not to sacrifice sex appeal, these clothes must therefore be see-through. It was left to Dolce & Gabbana to propose a practical solution: the gauzy white dresses of bandaged tulle that opened its art-themed show were worn over sturdy-looking bras and knickers.

I will be fascinated to see how this peekaboo trend will be worn in real life next spring. As will be the bloke sitting opposite you on the 7. 53 from Tunbridge Wells. Sheer clothes were also part of a broader mood in Milan that encompassed everything soft, feminine, light and wilfully escapist. Even Miuccia Prada had softened her outlook. Proposing pyjama suits printed with dreamy illustrations that were part-Art Nouveau, part- Gothic fantasy, she cut a curving edge to every hem and neckline in this beguiling collection. Full skirts, bell-bottom trousers printed with checkerboard patterns in sludgy colours, even the suede shoes with heels shaped like gnarled roots, all reflected her desire that every item be "all curves, no straight lines".

Prada also said that the Seventies had inspired this, at times, deliberately ugly but nevertheless highly desirable collection. That era also seemed to be the reference point for the rather less successful flared suits in flock- wallpaper patterns in Dolce & Gabbana's show. Floral-printed flared dungarees at Roberto Cavalli confirmed once and for all that the decade that style forgot will be influential next spring: a prospect almost as alarming as schlepping about town in a see-through tulle jumpsuit.

An emphasis on softness and femininity also translated into more predictable trends. The colour pink, as Katie Price and every four-year-old girl will no doubt be pleased to hear, appeared in almost every show. At Sportmax it was salmon-pink cargo pants or A-line duchesse-satin dresses. At Gucci it was bubble-gum pink and used on short teacup-shaped skirts that were equal parts punk and prom princess. For the usually conservative MaxMara, the colour was used for pervy latex bandeau tops or long rubber skirts that showed a flash of broderie-anglaise petticoat underneath.

On the whole, though, designers in Milan didn't bother to elevate the colour from its infantile connotations - apart from at Jil Sander, where Raf Simons' neon shades of pink and orange made for the sharpest collection of the week. Previously reluctant to radically alter the brand's trademark minimalist tailoring, this season he set about slicing up trouser suits into strange new proportions. Coats were fitted to the body and then enveloped with a second, looser layer of high-tech sheer fabric. Jackets were cut off above the bustline. This show had a clear agenda to change fashion and push it forward.

Also graphically strong was Karl Lagerfeld's latest collection for Fendi, where a simple theme of concentric circles was given the couture treatment. Long white skirts were decorated with bursts of rainbow colour, or precisely embroidered spirals of tulle or leather. Marni stuck to its offbeat colour palette and loose-fitting tunic dresses, this time decorated with subtle watery-coloured prints or giant sequins turned on their sides for a spiny effect. With the rest of fashion moving into Marni's characteristically loose-fitting silhouette, it made sense for this brand not to make a drastic change of direction.

Flounces and tiers of chiffon were the alternative to floaty tent dresses, and at Burberry Prorsum, Christopher Bailey's gold fringing and medals were the glitzy and oddly un-British take on his narrow dresses and luxurious coats. But a handful of designers managed to translate the unconstrained silhouette with a sophisticated and more classic approach.

Drapery and ruching, particularly in liquid jersey or silk georgette, is a way to flatter the female figure without either squeezing it into a fetish object or drowning it in a titillating transparent veil. In a romantic collection from Giorgio Armani, layers of stone-grey netting scarves, chiffon knickerbockers or bias-cut camisoles all made for a fluid silhouette, if one that frustrated for its fussier moments (why crystals on daywear?).

Over at Bottega Veneta, painstakingly ruched dresses in subtle shades of putty, cloudy grey and buttery yellow took the idea of Grecian drapery and gave it feminine structure, emphasising the bust and waist. For the fluidity of his elegant, knee-length dresses and silk-gabardine safari shirts, the brand's designer Tomas Maier produced one of the most sensual (as opposed to sexy) collections of the week. And while there can be no Versace show without brazen sex appeal, on that catwalk, too, it was the flow of fabric - liquid jersey in emerald green, coffee or bright yellow - that revealed an empathy with the women who will eventually wear these dresses.

Other upbeat moments of the Milan season were the fantastic prints that many designers painted on to the canvas of those long, sheer dresses. Dolce & Gabbana's splattered flower prints were joyful on its ballgown-sized dresses. From the tiny sprigged prints on his high-necked belle epoque blouses, to the giant purple tropical blooms hand-painted on his nightgown-style dresses, Cavalli's florals were best in show.