David Bohrer, White House via AP Members of the Northwestern University women's lacrosse team flip-flopped straight into a flap with their choice of footwear during a visit to the White House last July.

By LaMont Jones
Pittsburgh Post-Gazette No footwear in America declares "casual" louder than the flip-flop.

And now that summer has arrived -- along with heat, humidity, and more casual dressing -- flip-flops are all over the place. For women, the newest styles are more lavishly embellished, making the traditionally plain sandal look more like a wearable, walking work of art.

Flip-flops, however, remain taboo in most workplaces, even on casual Fridays. From banks and law firms to H.J. Heinz and the Allegheny County district attorney's office, they are considered inappropriate and not professional -- regardless of whether they were made by Payless or Prada.

From teller windows to executive suites at PNC Bank offices, "open-toe shoes are allowed, but not flip-flops" said spokesperson Darcel Kimble.

These Mystique Silver Gem flip-flop sandals are available for $89.95 at www.flipflopstyle.com. Click photo for larger image.

Named for the sound they make as they flip up and slap against the soles of the wearer's bare feet, flip-flops are among the oldest known footwear in history. Their airiness and simple construction -- a flat sole with a V-shaped piece that separates the big toe from the others with no closures for heels or toes -- made them popular in Asia, the Middle East and Africa long before the rest of the world caught on.

The Eastern ethnic influence on fashion, along with surfer culture, contributes to the current flip-flop mania in the United States. Internet sites devoted to the flip-flop and its sibling sandals have cropped up in recent years, from FlipFlopStyle.com to FlipFlopTrunkshow.com.

"It's a great stretch to think of flip-flops as ever being appropriate for the office, even on a casual Friday," said Constance White, eBay style director and former fashion journalist for the New York Times.

But the growing numbers of styles and variations have broadened the definition of a flip-flop, often making it tricky to determine whether someone is actually wearing a flip-flop.

Flip-flops are banned at Dickie McCamey & Chilcote, P.C., but the Downtown law firm's policy is more difficult to enforce because of the adornments that can obscure the style of sandal, said marketing director Deb Sindler. Pants, she said, can also make it more difficult to spot flip-flops in the office.

"The key is to know -- and this is where the danger lies -- when it's really a flip-flop and when it's crossed over into something else, when someone wouldn't look at it and immediately think, 'She's wearing flip-flops in the office,'" said Ms. White. "If it's that dangerous, just forget it. Don't try it."

In some workplaces, prohibition of flip-flops is a safety measure. In others, it's a sanitation regulation. But in corporate America, flip-flops are still uniformly perceived as unprofessional.

"I think we haven't gotten to the point yet where we're comfortable seeing an almost-bare foot in a business setting," said Ms. White. "We associate that bare foot with, 'It's too naked.' If your feet are revealed, perhaps your mind is not on your work. That is the implication, and that goes for men and women."

Regardless of employer restrictions, workers from Manhattan to Milwaukee will find a way around anti-flip-flop rules this summer, she predicted.

"I totally expect to walk into offices this summer and see people in flip-flops, men and women. And if it's a Friday, all bets are off."