Walt Robbins has never worn pantyhose. He hasn't experienced the firmness of a control top during a Houston summer or worried about snagging his hose throughout the workday. Yet he believes professional women should wear them.

Robbins was one of several men who responded to a recent Chronicle interview with style expert Lloyd Boston, who complained that too many women wear pantyhose out of habit.

Robbins, an operations manager with a bottled-water company, disagreed. "In the business world, dressing has gotten too relaxed," he said. "When a woman wears pantyhose, she looks put together and complete. It's one of those accessories that I think is classy and professional. It tells me that she cares about her appearance."

Robbins isn't the only traditionalist who believes in the old-school rules of corporate dress that dictate hosiery for women. But many women aren't playing by those rules. Unless their job requires them to wear pantyhose, they often go without.

According to NPD Group, a market research firm, sales of sheer hosiery dipped in the past two years to just under $1 billion from $1.3 billion.

"Women today don't want to wear pantyhose unless it's a special occasion, even though men generally like to see women in hosiery and hosiery products," says Sally Kay, president of the Hosiery Association, a trade organization that studies hosiery trends. "We have seen a decrease in use of pantyhose over the past 10 years, but other hosiery products (knee-highs, thigh-highs and footless hose) have increased."

The use of traditional pantyhose dropped in the early 1990s with the emergence of business-casual dress codes, Kay said. Manufacturers then began offering more alternatives, such as thigh-highs and footless hose.

Spanx founder Sara Blakely launched her first product, a footless pantyhose, five years ago because she dreaded wearing most pantyhose. Her hosiery and body-shaping products have become widely popular.

Pantyhose, which combine a panty and stockings into one piece, were introduced in the 1960s. They replaced stockings, which for centuries required women to wear an even more uncomfortable accessory ¡ª a garter belt ¡ª to hold them up. Even some men wore garters to hold up their stockings.

Today's pantyhose come in many varieties that do more than just enhance the look of a woman's legs. Some have anti-cellulite properties, moisturizers, graduated compression and even UV protection. Also, the use of spandex has helped make pantyhose more comfortable.

Kay sees dressier looks coming back, slowly. "It won't return to the days of Nine to Five (the 1980s movie featuring Dolly Parton), but we are seeing more pantyhose on the runway and in the workplace," she said.

With their spring 2006 collections, designers Marc Jacobs, Anna Sui, Gwen Stefani, Dolce & Gabbana and Celine all showed some form of legwear ¡ª footless or dark opaque tights, knee-high and anklet socks, even leg warmers. Fall collections continue to embrace the legwear trend.

Kay says the slow return of hosiery is an example of the fashion cycle repeating itself. The economy often influences shifts in fashion trends, she explains. When the economy is in a slump, dress tends to be more conservative; hosiery lends itself to those looks. The use of hosiery varies from industry to industry, she adds.

Fulbright & Jaworski, a national law firm with nearly 900 employees in Houston, dropped its dress code's pantyhose requirement last year.

"We saw the trend toward more casual dress in all of our offices and at other firms," says Jane Williams, the firm's chief human-resources officer. "Women are excited about it. The last thing I want to do is put on a pair of pantyhose when it's 100 degrees."

Continental Airlines went to business-casual weekdays in 2001, but flight attendants are still required to wear pantyhose while in uniform.

At M.D. Anderson Cancer Center and other hospitals, employees must wear some type of hosiery, including socks, for the health and safety of patients.

Suzette Brimmer, associate chair of fashion merchandising at Houston Community College, isn't an advocate of pantyhose but says they make a difference in how a woman looks.

"Pantyhose within a few shades of your skin tone can be flattering and can give you a finished look," she said.

Brimmer stopped wearing pantyhose regularly nearly a decade ago when she found more pantsuits available. "At first, my husband thought I looked naked. I asked him to try them on up to his knee. That shut him up."

Getting younger women to wear pantyhose is difficult, she says, since many of them would rather wear jeans than dresses in the first place.

While basic, old-fashioned pantyhose have practically become a no-no for fashion mavens, Brimmer says pantyhose may not survive if young women don't find them fun.

"If we can get Generations X and Y to buy into it, then hosiery will survive. But the no-hose wearers will always look for an alternative, unless we get to a point where we really want that sausage feel."