Calf-length, thigh-length or just-below-the-knee. With no "must-have" hem-line apparent in the autumn/winter collections, it seems we can finally dispel that tired hemlines-fall-in-a-recession myth. However there is a new theory in our midst. Denim. From catwalk to customer, could it be the recession that's sent us all mad for this hardy fabric?

Of course the American-born workwear is no newcomer to fashion's smorgasbord of trends. Since the arrival of Earl Jeans in the mid-Nineties we've retained a quiet demand for designer denim and, consequently, now barely bat an eye-lid at the price tag on a £200 pair of jeans. But the difference with this recent resurgence is that it goes further than luxury jeans brands. Today's trend encompasses everything from denim shirts to jackets and dresses, and is readily available from Matalan to Marni.

More pictures: denim is everywhere

Arguably, it was last September at Christophe Decarnin's show for Balmain that denim made its triumphant return. Paint-splashed, bleach-washed or ripped, the designer's use of this utility fabric set buyers scribbling in their notepads in the hope that with this wearable and sustainable trend, they just might be able to get people shopping again.

Denim was back on the fashion radar and, within a season, back on our high street. Gap launched into spring summer with a denim collection that far surpassed that of its standard jeans line, including a denim shirt that quickly became a favourite with fashion editors. Topshop cashed in on the trend with punk-style denim jackets and Zara played its part with high-waisted skirts.

For autumn/winter, our love affair with denim continues. M&S, French Connection and Oasis have focused on creating capsule ranges, while the luxury jeans brands are expanding their collections to encompass more than the standard jeans fare. Swedish brand Acne has launched a collaboration with Lanvin's Alber Elbaz which includes strapless evening dresses and trench coats in the fabric, while a host of new and directional denim brands, Current Elliot, R13 and C.R.A.F.T to name a few, should keep the tills ringing in Selfridges.

And it's not just catwalk-inspired pieces that have got us back in denim. "Staple jeans are performing outstandingly too,'' says Anita Barr, director of womenswear and childrenswear at Selfridges, who is responsible for the 15 designer denim brands currently available in store. Making the most of the increase in denim sales, Selfridges will next week unveil a denim-dedicated wall which is set to provide the focal point of 3rd Central, its new contemporary fashion space.

"Bringing our denim together is all about making one huge authoritative statement," says Barr, who credits the recession for denim's current success. "It's ageless, durable and wholly versatile and that is the key to fashion today. In terms of value for money, adaptability is what it's all about."

More pictures: denim is everywhere