actions -- in a good way. Biggest Challenge CNN: What is the biggest challenge you 've encountered getting where you are now ? M: Early on, when I wanted to go back to London and start my own fashion house, a very well thought-of executive in the industry said to me: Name one female designer that's come from Great Britain that has had any kind of global success. I wanted to prove him wrong. Obviously there have been great women from Britain in design, but actually there are fewer than I thought. So that was a bit of a hurdle for me. From day one I 've never worked with leather or fur. I do n't work with PVC, and I 'm very conscious in the sourcing and manufacturing of fashion. That's a hurdle, that's a challenge, but it's a worthwhile one. CNN: Do you feel a lot of pressure from the industry because you chose to go down the sustainable fashion road ? M: It's been difficult, it continues to be difficult, but I 'm OK with difficult, it's what keeps me on my toes. I 've had people say to me: You 'll never sell handbags, you do n't work with leather and leather is luxury. To me it's the complete opposite, leather is everywhere, it's so cheap a material, it's so mass produced. Over 50 million animals a year are killed just for fashion. For me it does n't have a luxury element to it. CNN: So you 're comfortable flipping that notion on its head, that leather is luxury ? M: Lots of