The Brand: Yves Saint Laurent/Saint Laurent
The Signature: Le smoking jacket
The Origin: Five years after his label's 1961 launch, Yves Saint Laurent stuck gold with his feminine take the classic men's suit. Women went wild for the full-on gender-bending look—a tailored pantsuit worn with a fedora and stilettos—especially the sleek, slim le smoking.
The Evolution: Not does nearly every contemporary label out there right now carry some sort of le smoking-inspired boyfriend blazer, but Saint Laurent (as the label was recently renamed by its current creative designer, Hedi Slimane) sells the style as part of its "permanent collection." And while it'll set you back nearly $3,000, remember that it's been unwaveringly cool for over 50 years; so really, there's no way you'll get sick of this style.
Yves Saint Laurent Spring 2000 HC (Giovanni Giannoni for WWD), Saint Laurent Spring 2013 RTW (Giovanni Giannoni for WWD), via YSL.com