I am riveted by extreme sports like big-wave surfing, 'megaramp' skateboarding and half pipe snowboarding. I am fascinated partly because the sports are so exhilaratingly acrobatic. But I am also captivated by the fear that a terrible accident might happen at any moment. And accidents do happen.

I find titles the hardest thing. I was worried that 'Waste Land' was too much of a downer. For me, 'The Crash Reel' confronts what the film is about: it's not just about the reality of a crash, it's about the extremity we all face, and what happens when life crashes on you.

I remember when the Berlin Wall fell and suddenly intractable problems get solved.

I am riveted by extreme sports like big-wave surfing, 'megaramp' skateboarding and half pipe snowboarding. I am fascinated partly because the sports are so exhilaratingly acrobatic. But I am also captivated by the fear that a terrible accident might happen at any moment. And accidents do happen.

I can ask someone to let me into all aspects of their life for several years, but people have got to have that gift: that courage and that talent for opening their lives to the camera. Being candid is a gift, and that's what the audience responds to. Part of it is me asking, and part of it is just their inherent talent, which is what you are looking for when you make documentaries - people that are really going to let you in on what they are going through.

Why is nobody questioning the sanity or suicidal tendencies of Everest ascenders? It's kind of a question of framing: How do you frame these activities? We frame them as freedom-loving, exciting, progressing sports and they are. But there are other ways to frame it. It's also true that these young men, neurologists say that their frontal lobes aren't developed yet - the long-term planning part of the brain.

There's a theory of accidents that I studied when I was making a film about nuclear weapons: you can never eliminate accidents, because the measures you introduce to prevent accidents actually produce more accidents. That's certainly true of this sport; you're flying over 40 feet of what might look like snow, but it's hard as ice, it's as hard as pavement. You're doing acrobatic spins and tricks, 40 feet above pavement, essentially. There's been more accidents since, and there are going to continue to be more accidents, that's the nature of the sport.