One little strip of fabric has the power to completely transform a woman's silhouette-and in some cases, her life. I'm talking about none other than the bra, and as the author of the best-known guide to all-things bras The Bra Book, I'm approached regularly to help women navigate through the mazes of numbers and letters to find the magic combination that's going to lift and support.

I recently took three New York City-area women of all different ages and body types to Manhattan's Calvin Klein Underwear store to show them how the right bra could instantly change their bodies. But don't just take my word for it, see the transformations for yourself in their before and after photos!

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