Behind every great woman is a great bra. A strapless or low-back top worn for special occasions can necessitate special lingerie. Two types of specialty bras, bustiers and longline bras, can push, pull, and suck into place what needs to be to create the perfect look.
Lingerie retailer barenecessities.com (reference 1) explains a bustier as a modern version of a corset, designed to accentuate a woman's curves. Bustiers are strapless garments with flexible boning for structure and support, and they extend to the hip.
A longline bra may provide more control than a bustier, particularly underneath clothing. Slimming stomach support is often a feature in longline bras. A three-quarter style stops at the hip, while a full-length extends past the hip, notes longlinebra.net. (Resource 2)
Bustiers are typically designed to define a waistline and accentuate a bustline. Longline bras are more supportive and smoothing; they may also help with posture, because the boning make them more difficult to slouch in.
While bustiers are almost always strapless, longline bras can be found in strapped styles, making them advantageous for women with fuller busts. Both longline bras and bustiers may come with garters for attaching stockings, rather than wearing pantyhose.
Tight or constricting lingerie such as bustiers have been out of fashion, but are returning as more comfortable fabrics are available. Celebrity blogs such as imnotobsessed.com(Resource 3) tout shapewear as the "best-kept secret" of the stars.