Fashion has shifted so dramatically that designers who once captured the tempo of the times, who lived on the very edge of the next new thing, now reek of obsolescence. Those dark, brooding clothes that exuded enviable intellectualism just a moment ago now look staid and cliched.

This transformation from relevance to irrelevance does not occur along generational lines. A young designer stuck in a mood of black cynicism can just as easily become outmoded as a veteran designer who fails to realize that women no longer travel with steamer trunks.

Unrelenting minimalism looks unduly ascetic now. But flaunting jawbreaker-size jewels isn't quite right either. While a designer can still work in a palette of black and white, there has to be a breathy lightness, an air of optimism, even if it is only a hint. That was part of the problem with designers such as Ennio Capasa at Costume National, who showed his spring collection Monday. The clothes looked studied and lethargic, devoid of the fun that has designers giggling as they fling sequins and beads at every bit of fabric in sight.

Darkness isn't the only harbinger of lethargy, of course. Valentino presented a collection filled with creamy tones of beige and parchment and a host of pastel shades. And still the models lumbered along, never once mustering the frisson for which Valentino is known.

Instead, the surprises came from unlikely places. At Louis Vuitton, where every model looked as if she should be riding in a '50s convertible, slim pants and scarf halters had one longing for a sloe gin fizz on the lido deck. Martin Margiela at Hermes found hidden spark in a crisp white shirt and fluid white trousers. Cut to perfection and in the most luxurious fabrics, even such mundane notions can suddenly become as rare and blissfully indulgent as a vase overflowing with exotic white orchids. Dries Van Noten's filmy lace tops and peasant smocks read like steamy love poetry in which the implied is more enticing than the revealed.

And this afternoon, inside an expansive warehouse just outside of Paris, it rained. Designer Junya Watanabe created the indoor rainstorm with sprinklers and hoses, sending water rat-a-tat on a grate-like metal catwalk. Initially, one had the horrible feeling that something pretentious and unduly torturous of women was about to occur. Indeed, whenever designers build any contraption with metal and levers, the outlook is rarely good. But this time Watanabe was not indulging his artistic vision. Rather, he simply wanted to offer proof that his clothes lived up to their waterproof billing.

The first models emerged on the runway in A-line skirts and simple shirts. Their heads were covered by cheerful kerchiefs knotted just under the chin. Their feet were tucked into practical plastic slides. They approached the artificial rain shower slowly, tucked in their chins and dashed through. And then they stood in front of the photographers, not a wet mark to be seen.

While water-repellent fabric is by no means a recent discovery, Watanabe used it to bring charm and wit to his collection. There were simple sheaths that unzipped and reversed. A wrap skirt could be unbuttoned and rewound in the opposite direction so that a gray pleated skirt became a plastic-coated gray wrap skirt outlined in neon green.

There were slim black trousers with shrunken blazers that deflect water, too, as well as trim shirts that can emerge from a downpour utterly unfazed. Colorful sheaths have block prints of flowers, and dresses have minutely pleated hems like rows of freshly trimmed hedges. It was a delightful collection that used technology to its advantage. It kept tricky cuts to a minimum and remained focused on an often overlooked reality: Sometimes the most straightforward notion is the best.

Issey Miyake

The program notes for the Issey Miyake presentation Monday read more like a chemistry manual than a description of clothes. The garments had been injected, heated, molded, subjected to ultrasound and so on. One half expected someone to wander onto the runway, zap a dress with a bolt of electricity and pronounce it: Alive! But instead, this was simply more of the fabric experimentation for which the Issey Miyake label is renowned.

This season, however, marks a quiet change at the house. The founder and namesake stepped down from the signature collection, turning it over to his longtime protege, Naoki Takizawa, who has been designing the label's menswear line since 1993. Miyake will focus his attention on further experimentation with fabric and a procedure known as APOC (A Piece of Cloth), in which a single garment is constructed from a continuous band of fabric.

The collection on the runway was filled with pajama-like trousers and tunic tops. There were stretchy bloomers and undershirts and clinging dresses printed with textural patterns. And there were mesh-like dresses with phantom bustles and panniers. It was as though the padding for such derriere and hip enhancements were removed but the fabric remained stretched from the memory. The look is unattractive, and while there are those who might ooh and aah over the technology to accomplish such a feat, saner folks would remind them that technology is only as good as the hand that controls it.

The finale of the presentation, with a gaggle of young models prancing down the runway with the designer, was striking not because of the clothes but because of the apparent youthfulness of the giggling mannequins. Wearing what was for all intents and purposes underwear, they looked like school girls at an enormous slumber party. That image underscores the problem with the collection. From the hooded windbreakers and clear plastic jackets to the boyish shorts, the clothes look as though they were made for elementary school and not for the grown-up world.

Valentino

By contrast, Valentino's collection managed to add at least 15 years to each of the young women who walked his runway today. There wasn't much enchantment in this collection. Instead, it seemed tired and creaky and had the labored feeling of a woman accustomed to changing her clothes three and four times a day--for lunch, for shopping, for cocktails, for dinner--but no longer able to remember why she ever thought that was a good idea. The jackets had a leaden quality; the knits looked stuffy.

One wishes there had been more of the skirts and dresses embroidered with silk blossoms, a touch that injected momentary surges of energy wherever they appeared. In a season that has been defined by sweet indulgences, Valentino, a master at froth and spun sugar, presented a collection that came on like liver and onions.

Louis Vuitton

At Louis Vuitton Monday, designer Marc Jacobs presented a collection full of substance and ideas. Last season, the collection was overwhelmed by the handbags, tote bags and oversize pieces of luggage hauled out by every model. It seemed the clothes had been whipped up at the last moment because the models needed something to wear when they showed off all of those Louis Vuitton leather goods.

This time, the focus was on the clothes. There were slim trousers and knee-length skirts with rounded hems. There were loose-fitting halters that looked as if a scarf had been hastily tied around the body in some magical way. There were geometric patterns on trench coats and dresses. And there were bolder, abstract prints in a wash of watercolors and sprinkled in silver sequins. The collection had the jaunty feel of '50s sportswear, which, in our blind nostalgia, was a time when folks spoke in quick blasts of witty repartee and everyone always managed to look splendid.

This was no retro collection, however. Instead, it merely borrowed a bit of attitude from a bygone era. The clothes were full of the informal elegance, confident sex appeal and ironic glamour--as with a patent leather logo-covered cummerbund--that is the mark of this moment in fashion.

Dries Van Noten

Dries Van Noten's Monday presentation did seem to emerge from another time, an era when women took an evening stroll, a shawl wrapped around their arms, the click of their heels echoing on cobblestone. It was dominated by full skirts--there wasn't a single pair of trousers on the runway. The skirts, sometimes gathered at the waist and at other times blossoming gaily from a narrow waistband, were cut from aged floral prints or were decorated with metallic floral embroidery. They were topped with billowing lace smocks, tiny lace blouses and shrunken jackets wrinkled with character. The shawls, which encircled the shoulders, were held in place by heirloom brooches.

The collection, with its rich colors and antiqued fabrics, suggested romantic heartbreak and the daydreams of troubled lovers. It is difficult to imagine such melancholy fantasies making the transition from the runway to city streets, particularly the full skirts accessorized in such an Old World way. But Van Noten tapped into this season's emphasis on womanly blouses and jackets as light as a feather. And they would lose none of their poetry even in the midst of the most intimidating urban jungle.