No cleavage.

No midriffs.

Bra straps should fit smoothly under tanks.

Opt for a ruched blouse instead of a lacy camisole.

The slip dress is a done deal (unless it's in black and you wear it with strappy sandals.)

I know this is a switch. And it is summer. Why not just bare it all? The truth is that all those cleavage-baring tanks and deep-V tops we paired with expensive jeans now look so passe, so over, so Jersey Shore circa 2004.

Local boutique owners agree:

"Hardly any of the clothing this spring is about skin," said Andrea Chila, owner of Pileggi Boutique.

"There is a lot less cleavage. Instead we are seeing lots of billowy, oversized tops and detailed necklines. More crewnecks and ruching. Nothing is plunging. Skin isn't sexy any more."

I noticed a shift in my dressing habits in early spring. All of a sudden I stopped opting for the frilly, peekaboo camisoles to wear under suit jackets and V-neck sweaters. Instead, I went for the higher, opaque tanks or a starched shirt.

Shift dresses with bateau necklines seem particularly appealing - especially when paired with a thin belt. T-shirts that scoop just below the collarbone feel better.

Somewhere along the way, I tired of trying to tuck in bra straps and pulling up strapless dresses. Off-the-shoulder shirts drove me nuts. I never felt finished.

This new era flies in the face of modern-day fashion because it's proof that rules are coming back to clothing. People are tired of looking willy-nilly, but they don't quite know how to fix it. Khakis have been a part of their lives too long.

This new sophisticated look reminds us of an earlier time when many clothing options weren't that affordable. With gas creeping up to $4 a gallon, those times seem to be returning along with the fashion. Something tells me a few good, well-made pieces are are much more closet-friendly than grossly ostentatious fashion.

"I'm looking forward to a time when people return to a standard of appropriateness," said designer Sara Van Aken, in a yellow pencil skirt and wrap blouse, one recent afternoon. Van Aken was particularly excited that in stylish circles, cleavage is now relegated to post-cocktail-hour.

Meghan Sander, 32, of Northern Liberties is excited about the change, too.

"The fashions are more ladylike, more elegant," she said. She had artfully placed a yellow tank under a olive-green sundress.

"It's colorful. It's demure. It's definitely more to my taste levels."

These rules aren't to stifle. I like to think of them as a practical shift. Think fitted wide-legged pants, pencil skirts, and dresses. My girlfriend calls it the sexy secretary look. Fashion likes to think of it as a return to the 1950s.

"People are trying to channel the '50s look," said Jennifer Ramsey, owner of Echo Chic on Sansom Street.

"I think what's happening is that tunics and shirts are getting shorter, so the necklines are moving up. And instead of pairing them with jeans, they are opting for trousers and flats."

It's also about proportion. While blouses are fitting better, some skirts are getting shorter.

"It's about opposite attractions," said Nicole Fischelis, fashion director at Macy's East.

"Long and short, thin and fuller. Voluminous blouses with skinny skirts. Tight T's with a full skirt."

But unlike recent moments in fashion, when clothing was billed as appropriate for all ages, today's ultra-minis are only being marketed to teens. So ladies, don't wig out and try to squeeze into something that's not you. Continue to get your grown woman on.

And remember the new rules!