5 Cult Brands On What Makes An 'It' Bag

What exactly makes an 'It' bag? Is a cult carryall a piece that possesses classic features and fabrics, or does its must-have nature lie in its ability to capture the zeitgeist? And is it the brand that makes it that way, or is it the person who carries it?

'It' bags certainly don't have to be functional — just look at 1995's Lady Dior, a gift from France's then first lady Bernadette Chirac to Princess Diana, which didn't hold more than the bare essentials. But in recent years, several brands have produced coveted and practical bags that have quickly made their way from the runway to the arms of street stylers to fast-fashion imitations: Phoebe Philo's structured Céline Luggage Tote caught the attention of everyone from dedicated Philophiles to Kim Kardashian, while Gucci's Marmont comes in all shapes and sizes — from top-handled to chain-laden shoulder-strapped to the belt bag — has defined the season.

To find out what truly defines an It bag, we quizzed five of the brands of the moment. From what makes a timeless piece to the styles you should invest in this season, we're breaking down the method to the It bag madness. Who knows, one of these could be a future classic.