Women's Double-Breasted Blazer

Two columns of buttons and a front panel that crosses the body: a double-breasted jacket laps one side over the other by roughly 3 to 5 inches and fastens on both sides of the chest. That overlap is the whole design. Peak lapels, cut pointing up toward the shoulder, almost always come with it, and so does a hidden inside button, the jockey button, which anchors the underneath panel flat.

Two layers of cloth across the chest change how the jacket behaves. The front holds a stronger line than any single-breasted version manages. It runs noticeably warmer, which narrows your cloth choice in summer to about 240 grams per square meter and below. Button placement then sets the proportions: buttons spaced wide apart broaden the shoulder line and shorten the torso. By comparison, a narrow set placed low lengthens it. One rule has no exception, and it is that a double-breasted front must be worn closed, since the loose panel hangs forward and swings when it is not.

A Single-Breasted Blazer gives you the option of wearing it open, which serves an overheated office far better. The Oversized Blazer often borrows this crossed front, and the two features together demand something narrow underneath or the outfit loses a waist entirely. Against a matched Trouser Suit, a double-breasted jacket adds formality without adding a third garment. This is roughly the job a waistcoat does in menswear.

Evenings, weddings and rooms where a plain jacket would disappear are where it works best. Long torsos gain the most, because the crossed front needs vertical room between bust and hip to lie flat. Cooler months suit it, since the doubled front reads heavy much above 75 degrees. Anyone who takes a jacket off at their desk should skip it, as it looks unfinished the second it opens and it creases fast over the back of a chair.

Button it and study the front edge in a mirror. The overlapping edge should drop straight, and an edge that curls outward or lifts means the jockey button inside is missing or badly placed. Sit down still buttoned and check that nothing bites at the hip. Ask before ordering a sleeve shortened, because a cuff with working buttonholes has to be shortened from the shoulder instead, and that costs several times more. Keep it on a wide hanger with the front closed so the wrap holds its shape.