Less about a hit of thigh than movement and figure-flattering shape, there's a reason slit pencil skirts resurface every few decades - previous heydays include the postwar forties and power-suited eighties - as they did on this spring's runways, which referenced both of those eras. Be warned, though: These slim numbers sit, as their history suggests, somewhere between pencil pusher and pin-up. Here's how to draw the line.
1. Avoid referencing Melanie Griffith in the eighties classic Working Girl (and we're not just talking about the hair). Translation: A skirt suit is way too matchy-matchy, so switch it up with a contrasting blazer and a hit of bright colour underneath. Anything printed or blue, like at Aquilano Rimondi (above left), looks best with black.
2. Save the super-high slit for the discotheque, not your desk job. Opt instead for a moderate show of leg that hits lower mid thigh.
3. To evoke just the right amount of pin-up, wear heels. Like the skirt, they'll elongate your shape and therefore flatter. The power heel, after all, is the new power suit.