By Stephanie Clifford for The New York Times: In one store, you're a Size 4, in another a Size 8, and in another a Size 10 - all without gaining an ounce.

It's a familiar problem for many women, as standard sizing has never been very standard, ever since custom clothing gave way to ready-to-wear.

So, baffled women carry armfuls of the same garment in different sizes into the dressing room. They order several sizes of the same shirt online, just to get the right fit.

Now, a handful of companies are tackling the problem of sizes that are unreliable. Some are pushing more informative labels. Some are designing multiple versions of a garment to fit different body shapes. And one is offering full-body scans at shopping malls, telling a shopper what sizes she should try among the various brands.

"For the consumer to go out and navigate which one do I match with is a huge challenge, and causes frustration and returns," said Tanya Shaw, an entrepreneur working on a fit system. "So many women tie their self-esteem to the size on the tag."

As the American population has grown more diverse, sizes have become even less reliable. Over the years, many brands have changed measurements so that a woman who previously wore a 12 can now wear a 10 or an 8, a practice known as "vanity sizing."

In men's clothes, the dimensions are usually stated in inches; women's clothing involves more guesswork.

Take a woman with a 27-inch waist. In Marc Jacobs's high-end line, she is between an 8 and a 10. At Chico's, she is a triple 0. And that does not consider whether the garment fits in the hips and bust. (Let's not get into length; there is a reason most neighborhood dry cleaners also offer tailoring.)

Read more at The New York Times