Summer Trends 2007

• An underwire or built-in bra gives structure and support, says Weiss. Straps also help prevent sag.

• Keyhole or string-bikini triangle tops and demi bras aren’t ideal for big busts, says Yang, since they don’t provide enough coverage or support.

Swimsuits at left: Polyamide-elastane printed one-piece, Fantasie, $110; figleaves.com. Nylon-spandex bikini, top ($110) and bottom ($79), Shoshanna: at Saks Fifth Avenue.