Suiting up to go to the office for women used to be about as boring as it sounded.

More often than not, the big fashion decision each morning was whether to choose the navy blue or the gray. Or perhaps to go with the floppy bow at the neck -- or not.

"Ten years ago buying a new suit wasn't very exciting," says Nancy Chistolini, vice president of fashion merchandising for Hecht's. "It was just replacing one tailored navy blue, black or gray suit with another."

Well, women's suits have come a long way, baby.

From crepe wool Chanel suits in feminine pinks with contrasting black piping to screaming pink affairs from Gemma Kahng decorated with large, ornamental buttons and bright colors interspersed with patches of contrasting color, suits definitely have taken a turn for the brighter. There are even camellia-print jackets in celadon and ivory from Ann Taylor complemented by flirty, pleated silk chiffon skirts.

And not only have they come a long way, but these days, suits go farther, too: from office to dinner and, increasingly, to black-tie events.

But when women began entering the work force, there was no one to imitate for office fashions but men, says Ann Steele, curator of the Baltimore Museum of Industry. Subsequently, women's suits had a uniformly masculine appearance.

"Even in the late Victorian era, women wore shirtwaist blouses, long black or dark skirts and matching, short cropped jackets to the office," says Ms. Steele.

To be sure, there was the occasional variation, such as flirty peplums attached to the severe, big-shouldered jackets of the 1940s or the more colorful look of the 1960s. But, by and large, these trends faded in and out, always to be replaced by more traditional masculine looks.

"From [the Victorian era] on, women's office wear has often been severe and masculine. Even in the '60s, with the rise of women's lib, women wore tailored pants suits to the office."

And throughout the 1970s, as women infiltrated the white-collar job market, office wear for women continued to favor menswear designs, with mono-color suits complete with tailored, fitted jackets and A-line skirts the dominant silhouette.

No more.

Perhaps it is because women feel increasingly at ease in the job market, perhaps designers were merely bored with using darker hues alone, whatever the reason, women's suits have gradually, almost surreptitiously, taken on a whole new look. "Femininity is featured at the top for spring '91 suits, especially in the 'desk to dinner suits' that double for work and social events," says Nancy Powell, divisional merchandise manager for Joseph A. Bank.

Indeed, the softer, more feminine look is reflected in designers' choice of materials, as well. "Even the fabrics, such as rayon blends and silks, are softer and drape more gracefully," she adds.

"Today there's less of the hard, finished gabardines, and more fabrics that offer a professional, finished look as well as softness and elegance," says Susan Bixler, president of the Professional Image, a consulting firm in Atlanta. Ms. Bixler favors soft, wool crepe suits because they wear well all year long and are professional, comfortable and wrinkle resistant.

"The new suit combines our love of sportswear and separates, where we are attuned to seeing several bottoms that can go with the same top. So it's easy to see suits in something other than a singular color," says Jane Ann Simpson, vice president of Nan Duskin's Baltimore store. "They're newer, fresher, more accepted and easily understood by the consumer."

Ms. Powell agrees. "Even though some traditional menswear-type suits are still required or preferred in some offices, many women are buying more separates for more color and variety," she says.

In keeping with a softer image, spring suits also favor softer construction. At first glance, some of the softer spring suits look like dresses, but actually feature a soft, short top with a matching skirt.

Jackets can be long, flowing and unstructured for an Armani look, cropped short for a Chanel look, or nipped in at the waist for a more flirty silhouette, and a number are lightly tailored with short sleeves. Many spring jackets also sport elaborate trimmings, such as braided trim, elegant jewelry buttons or a pocket hankie and can be worn alone or with a blouse or camisole. The jackets are paired with short (at or just above the knee) unconstructed slip skirts or maybe a softly pleated skirt.

The softer, more diverse suits also offer a big advantage -- they're more comfortable than suits patterned after menswear in which the arm holes often were too high, the jackets too tailored, and the skirt too slim to work comfortably.

"The new suits with less padding, looser, push-up sleeves and skirts with pleats or completed slits are more comfortable for work," says Ms. Bixler. "Also, menswear-type suits follow the body closely and are less than ideal for anyone more than 15 pounds over her ideal weight."

The most dramatic change in suits this season, however, is color. The idea is to mix bright colors and even prints to create a new look.

"Color is important; it is making the statement," says Tom Marotta, a buyer for Nan Duskin. "It started with [Coco] Chanel bringing in bright colors, and now there's color blocking, putting together colors like pinks and greens, for a whimsical, fresh look."

"One of my favorite suits is tangerine orange and very professional, but I wouldn't have been caught dead in it three years ago," says Ms. Bixler, whose second book, "Professional Presence" (Putnam) is due out this fall. "The business eye today is more accustomed to color, so most business people won't freak out at the new suits, as long as they're not 5 inches above the knee or made of chiffon."

Many women may prefer to reserve suits with elaborate piping and jewelry buttons for dinners or cocktail parties, but that's not necessary, says Mr. Marotta.

"These suits can be worn during the day, and the jackets can be paired with pants or a different skirt for a fresh look," he says. "These suits are not just for evening wear."

The suits, however, do make an excellent substitution for evening wear, especially if you're traveling and don't want to worry about packing a gown, says Ms. Chistolini. "The dinner suit has been around for a few seasons, but it's becoming more popular. Suits, especially crepe or silk suits, are perfect for a black-tie affair."

SUITABLE OPTIONS

* Try a few small changes to take a suit from day to evening. Switch to big, pretty earrings.

* Add lots of long gold or pearl chains for a Chanel look. If you wore your suit jacket with a blouse at the office, try wearing it alone or with a camisole for an evening event.

* "Use a full-length mirror when adding accessories," says Susan Bixler, president of the Professional Image, a consulting firm in Atlanta. A broach at the throat or on the lapel can enhance your look, but it needs to be placed appropriately.

* Mix and match your suits for a fresh look. A fuchsia jacket looks great with a black, lime green or red skirt. To update your favorite suit, try adding braided trim or switching to ornamental jewelry buttons.