Buyers, journalists, fashionistas and bloggers have descended on the capital to check out the latest trends and cutting edge talent.
There will be 58 catwalk shows over five days, including well-known British brands Burberry, Mulberry andVivienne Westwood.
They'll showcase their latest spring/summer 2014 collections alongside newer talent and labels.
The recovery in the domestic economy may be fragile, but a July study by Ledbury research said the UK luxury industry is set for strong growth, with 83 percent of luxury brands expecting sales to grow this year.
It's a significant creative industry in the UK - contributing £21 billion to Britain's £1.6 trillion economy, and supporting around 800,000 jobs.