By Eric Spitznagel

Remember the late 1990s and early 2000s, when “casual Friday” was a naughty thrill? How innocent we were. In the past decade those seemingly harmless polo shirts and khakis have spawned a five-day sartorial office free-for-all that’s led to low-cut jeans and “tramp stamp” tatoos. According to a 2007 Gallup poll, the most recent data available, 43 percent of workers said they regularly wore casual business attire at the office, up from 32 percent in 2002. Even scarier, the lax precedent has allowed them to make their own decisions about what’s acceptable or, worse, cool.

The C-suite is striking back. A survey released in June by the Society for Human Resource Management found that only 34 percent of bosses officially permitted casual dress among employees every day—a dramatic drop from 53 percent in 2002. Some executives are hiring image consultants and fashion experts to crack down on everything from muumuus to Little House On the Prairie-style pioneer dresses. “American society has become so ridiculously casual,” says Clinton Kelly, co-host of the Learning Channel’s What Not to Wear. The problem, he suggests, may be the lack of office fashion role models. “Outrageous people are getting the most attention now,” he says. “Kids coming out of college are watching Lady Gaga on YouTube (GOOG). They don’t understand that Lady Gaga is selling albums, and they’re in accounting. A meat dress just doesn’t fly at the office.”

Popularized in Silicon Valley, the casual office look has always had noble intentions. “At Google (GOOG) we know that being successful has little to do with what an employee is wearing,” says Jordan Newman, a spokesman for the company. “We believe one can be serious and productive without a suit.” That may be the case for engineers dealing with complicated algorithms. However, professional image coach Lizandra Vega remembers meeting a male worker at the New York staffing firm where she’s a managing partner. He arrived for a meeting in thin white cotton slacks—and no underwear. “He was,” she recalls, “hanging loose.”

Even upper management isn’t immune to terrible dress habits. Diane Gottsman, owner of the Protocol School of Texas, recalls teaching a business fashion workshop in Houston last year during which she met an executive “wearing a straw paperboy hat pulled sideways,” she says. “He had on suspenders and black-and-white spectator shoes. He asked, ‘What do you think of my look?’ ” Gottsman tried to be diplomatic, suggesting he take off his hat indoors. “He couldn’t do that,” she says. “The hat helped him with his ‘swagga.'”

Workers may not like rules, but some need them. A 2002 survey by the recently shuttered department-store chain Mervyns revealed that 90 percent of office workers didn’t know the difference between formal business attire, business casual, and just plain casual. However, companies such as General Electric (GE) force them to make these distinctions every day by asking that they “use good, professional judgment,” as GE puts it. Ginger Burr, president of Total Image Consultants in Lynn, Mass., recalls a fashion workshop she conducted with a national bank. “We were talking about sandals,” she remembers. “There seemed to be a consensus that sandals shouldn’t be worn. Then this beautifully dressed female executive walked in wearing sandals, and said, ‘We should be able to wear nice sandals.’ When you get into personal taste, that’s where it becomes tricky.”

Sandy Dumont, an image consultant from Norfolk, Va., believes the biggest challenge in overhauling an office worker’s wardrobe is avoiding hurt feelings. Her suggestion: Hire a professional image consultant. She was brought in to help a female employee at Rolex who was offending an executive with her “klutzy” footwear—which turned out to be orthopedic shoes. (“She had a slightly deformed foot,” says Dumont.) Fearing that a confrontation would offend the woman, Dumont led her on a guided shoe-shopping spree on the company’s dime.

Those accustomed to personalized business style aren’t taking these changes lightly. “The uniformity of dress serves the current American business model by pressing individuals into the service of the corporate person,” says Jack Tuckner, a New York employment attorney who briefly represented Debrahlee Lorenzana, a Citibank (C) employee fired earlier this year for wearing provocative clothing. “It’s a largely paramilitary model that eschews independent thinkers,” he says. In 2008, Tuckner was sued by a former colleague for allegedly wearing a “bondage collar” at the office. Tuckner denies the allegations. “As a fastidious dresser myself,” he says, “I’d be excessively worried about unsightly neckline bulges caused by the lock.”

In Britain the concept of business casual is being taken to extremes. The Naked Office, a reality TV series that made its debut in May, asked employees at several businesses to show up for work naked, ostensibly in an attempt to “explore whether flashing the flesh is the ultimate office equalizer”—and boost ratings. Seven Suphi, a behavioral change specialist and author of More Than Men and Make-Up, took part as an expert presenter on the show and says the experiment “had spectacular business results. One business secured their largest deal to date. Another is doing in a month what they previously did in a year.” Let us ponder why.

In America, such a radical redefinition of office norms seems unlikely. Carolyn Hawkins, spokeswoman for the American Association of Nude Recreation in Kissimmee, Fla., says even her staff rarely comes to work in the buff. “The AANR’s association headquarters is located in a downtown strip mall—no pun intended—with a storefront window,” she says. “As practicality and sensitivity to our neighbors dictate, we dress for the workplace. When we return home in the evening we remove the stresses of the workday world by removing our clothes.” For the moment, business casual appears to be in no danger of becoming no-pants-casual—but it’s still enough to make you pine for the days of khakis and polos.