One of my career ambitions was fulfilled working with John [Hurt]. I loved his work long before I ever had the idea of being an actor, so I was nervous to meet him. I was like a fanboy, like that annoying character on 'Saturday Night Live'. I'm sitting there. 'Do you remember when you were in 'Midnight Express'? Remember that scene you were in?' And he doesn't disappoint.

Whats fascinating is that when you write a script, its almost a stream of consciousness. You have an idea that it means something, but youre not always sure what. Then when you get on the set, the actors teach you.

At 23 it was all about acting. Today it's getting my kids to school, making sure that they've done their homework. I'm in my fifties, and I'm turning into a square.

I think filmmaking should be a wonderfully free collaborative process, and it so very rarely is. I often see directors as jailers of my talent.

So Harry Potter came in and it is nice that I have kids of the right age. I took them to London and they walked around the set and met Harry Potter and that is thrilling.

I applaud anything that can take a kid away from a PlayStation or a Gameboy. That is a miracle in itself.

Your own barometer is all you have to go by, and often what makes a good director is knowing when not to say something. On occasions you can find yourself on a film set where the person who is wearing the director's hat is only trying to justify his position.