The truth is, it's very hard looking back... we look at holocaust now with such knowledge and such a sense of the horror of what it was, that it's hard to believe even now that in 1930s and 1940s, before something like this had happened, that it could be impossible to imagine the extent of this horror.

In some ways, many of the skills you have as a producer on independent films also apply to making big tentpole films: You surround yourself with a brilliant director, great script and talented people in every department who are smarter than you.

I like stories that begin with characters. I like to be engaged and moved by the characters in the story. I want to be moved. I want to leave the cinema and think about what I've seen. My sensibility is quite eclectic and it doesn't matter if they are small or large films, I just want to make good films.

The films you're making have to be faithful to the material.

All we try and do is make the best films we can. If you do that then hopefully the audiences will come, and they have. Everything else is gravy.

Because actually it's really hard to get things made. It takes years. To fight the fights you inevitably have to fight, even when you've produced Harry Potter, you'd better have the commitment and the passion to knock down walls, not take no for an answer.

I'm interested in making films of all sizes. During this time I've made a film called 'The Boy in the Striped Pajamas', which is a modest-sized film. I was involved in 'I Am Legend' and 'Yes, Man', but 'Potter' is unique. There'll never be anything like 'Potter' again.