Men should not wear Chanel jackets. It's no good for the brand. It's an aesthetic affront. It's bad for men and troubling to the women who love them.

Everyone knows this except, apparently, designer Karl Lagerfeld. For his spring 2006 show Friday morning, he cut the house's signature soft tweed jackets specially to fit a man's broad shoulders. One of the jackets was black and there was a metallic chain draped around the man's waist. This vague swashbuckling flourish was pointless. This, after all, was no Johnny Depp in mascara. The skinny boy-man on the runway tried to tap into the swaggering testosterone of his Neanderthal ancestors, but he still looked like an uncomfortable fop.

The idea that a gentleman should borrow clothing from a woman's closet is not new. And it seems only fair since women have stolen so much from the wardrobe of men. But it is hard to recall an example of a female-to-male clothing exchange resulting in anything remotely attractive -- professional drag queens excepted. (And any professional drag queen would tell you that a Chanel suit can make a fellow look unacceptably boxy.)

There have always been men who have found a certain satisfaction in wearing women's clothes. Whether they simply feel more comfortable in them or enjoy confounding society, only they know for sure. We will not get involved in that discussion here. And recently, young men with a particularly slim physique have been shopping for jeans in the women's department. But jeans are essentially an androgynous commodity. It really doesn't matter whether they button to the left or the right.

A Chanel jacket is an entirely different entity. It has an iconic stature as the uniform of a certain class of woman. Woven into its lightweight tweeds are references to money, social standing, public identity and aspirations. It's too crowded a canvas on which to layer questions about gender. But Lagerfeld could not resist the challenge.

For spring, the designer professed to be inspired by the idea of Coco Chanel meeting James Dean. Whatever Dean may have been up to in his private life, it is hard to imagine that the public man would have donned something as elitist and old guard as a Chanel jacket. In his program notes, Lagerfeld included advertising images of the collection -- a Chanel woman posing with what was meant to be Dean's doppelganger. This faux Dean looked an awful lot like Oscar Wilde, but the woman looked splendid. When Lagerfeld refrained from distracting silliness, the clothes that he put on the runway -- and on women -- were filled with charm. There was a youthful cool and a lighthearted froth to this collection that included everything from a strawberry tweed circle skirt with a matching cardigan-style jacket to a beaten up, faded black motorcycle jacket and slim black pedal-pushers with a side strip of tweed.

One wished that Lagerfeld Gallery, the designer's own flagship brand, would have reflected the same sort of imaginative energy. The collection he showed Wednesday was a lovely display of dresses, some soft, others tailored with geometric cutouts. But it wasn't filled with any of the big ideas -- or even eccentric ones -- that have always seemed to flow so easily from the designer.

For years, the industry has marveled at Lagerfeld's capacity to create idea-packed collections for Chanel and for his esoteric musings at Fendi in Italy, while reserving still more creativity to feed his own collection. But for spring, Lagerfeld Gallery looked like the stereotypical middle child who received only a few crumbs of attention.

Such neglect couldn't come at a worse time. Having recently sold his brand to Tommy Hilfiger Inc., Lagerfeld stands ready to expand his business with a less expensive eponymous collection to be launched in New York next year.

The designer is one of the best-known figures in the industry, with his distinctive white powdered ponytail, fingerless gloves and high-collared shirts, but he has yet to create a signature style under his own name. While training an audience to expect a particular style or type of garment from a fashion house may be anathema to a creative spirit, it is a necessity when it comes to transforming a celebrity image into a brand name.

Paco Rabanne, Givenchy, Celine

Building new brands and rebuilding old ones is one of the greatest hurdles for many of the houses showing collections here. So many of the old design houses are engaged in the long process of finding their way after years of neglect. And, of course, this is a city where new designers come to prove that they are ready for a world stage.

Patrick Robinson showed his second collection for Paco Rabanne on Monday. It was stuffed with ideas, including references to the mod disk dresses that Rabanne himself designed some 40 years ago. Robinson based his collection on antique kimono prints juxtaposed with Space-Age silhouettes as defined by Rabanne. But the collection seemed to ricochet from one thought to the next, looking vaguely like Rabanne, a little like Helmut Lang, a bit like Balenciaga. It showed Robinson's technical talent but not his point of view. The house awaits that cornerstone before it can truly begin to rebuild.

On Wednesday, Givenchy relaunched its ready-to-wear under yet another designer. Since Hubert de Givenchy retired a decade ago, John Galliano, Alexander McQueen and Julien Macdonald have all taken hold of the creative reins -- in some cases to disastrous effect. Italian designer Riccardo Tisci's debut was not catastrophic, but it wasn't encouraging. In a tedious presentation, models with kohl-rimmed eyes somnambulated around a two-story white sphere that sat atop a white platform. These zombie-like creatures wore tight-fitting bandage skirts with a fluted hem and often sheer blouses. After about 10 minutes of watching these women with their "Dawn of the Dead" vacant eyes, one wanted to cry out: "Don't look at them! They'll steal your soul!"

Celine introduced the first collection from designer Ivana Omazic, who had been one of the anonymous members of the house's design team. She succeeds Roberto Menichetti, who had followed Michael Kors. Omazic designs pretty clothes in shades of tangerine, marigold and navy. She likes pleated skirts, short trench coats and trim cardigan sweaters. She mixes it all up to evoke the feeling of a well-to-do college coed or the sort of young socialite who considers a trousseau mandatory rather than a charming anachronism. Still, pretty clothes are not enough to recommend a designer fashion label. If a woman wants pretty, all she has to do is head to the nearest Ann Taylor. She can get a lovely wardrobe and keep cash flowing into her 401(k).

Stella McCartney, Rochas

Stella McCartney may be as famous as Lagerfeld, but her brand image is just as fuzzy. Her earliest positive notices came from her sexy suits, tailored with Savile Row expertise and hipster attitude. Her suits still look wonderful and she showed a few on the runway Thursday as reassurance that she continues to include them in her collection. But her skirts and dresses lacked the same energy and appeal. Her best dresses were those in a lively Jeff Koons print, but one had the uncomfortable feeling that it was the work of the artist and not the designer that made them so compelling.

Only the most devout fashion aficionados would recognize designer Olivier Theyskens, with his slight figure, long dark hair and almost cherubic demeanor, but he slowly and steadily is building a new signature style for the French fashion house Rochas. In the collection he showed Wednesday, he continues to tinker with a long, lean silhouette that possesses a shy austerity and has proved to be more erotic than any bold display of cleavage ever could be.

He offered a few slimly cut trouser suits, but the real focus of this collection is on floor-length skirts topped with loose tank tops that swing seductively low without plummeting to the lower back. His evening dresses -- and despite their often rustic appearance, they are mostly appropriate for evening unless one plans to live out a "Wuthering Heights" fantasy -- have demure butterfly sleeves and keyhole necklines. And one of the most glorious gowns of the season is his simply cut dress with its slim skirt embroidered in flowers evocative of Monet's paintings at Giverny. When people talk about "wearable art," it most often turns out to be some terrible cloak or tunic that makes a woman look as though she is wearing an area rug. This dress captures the grace and the emotion of art. It is a pure, visual pleasure.

Dries Van Noten

More than simply redefining a fashion house that essentially had no image with contemporary customers, Theyskens also is changing the expectations for evening attire. He, along with designers such as Alber Elbaz, who will show his Lanvin collection Sunday evening, and Dries Van Noten, who presented his spring line Wednesday, have upended the assumption that eveningwear automatically means high heels and bare skin. They have offered an alternative that is just as likely to make a woman the center of attention but that also allows her to be more comfortable and more covered. These designers have championed evening flats and long sleeves. They practice the art of seduction through the judicious selection of fabric, structural details and only the coyest peeks of silky flesh.

Van Noten opened his show with garments that called to mind the golden light of a late-summer evening. The skirts grazed the floor and trailed trains of cascading ruffles. A strapless silk dress in quiet ecru revealed the shoulders, of course, but the airy transparency of the fabric suggested the silhouette of the body below. The seduction was all in the shadowy curves.

These designers are not taking the easy way out. It is not challenging to design a halter dress or to cut a gown with a particularly low neckline.

That's the sort of sex appeal that has become a cheap commodity thanks to uninspired designers, music videos and practically every starlet who has walked a red carpet. It's much harder to tease sensuality out of mystery and understatement. Sometimes, of course, these defiant designers fail, and the resulting clothes are more matronly than enticing. But when they succeed, the effect is all the more powerful.

Un-boss tweed: In designing a Chanel jacket for men, Karl Lagerfeld professed to be inspired by the idea of Coco Chanel meeting James Dean.

Stella McCartney's dresses still haven't caught up to her sexy suits. A bandage skirt and sheer top, right, from yet another designer for Givenchy, Riccardo Tisci. Below, from left, Lagerfeld Gallery showed a designer stretched too thin; Patrick Robinson still trying to put his mark on Paco Rabanne; and Ivana Omazic's first collection for Celine.

Olivier Theyskens's long, lean silhouette for Rochas, left, and two offerings from Dries Van Noten, all of which redefine the notion of eveningwear.