Making sure that the geography and timelines work is always the hardest part of writing. But you owe it to the readers to get it right!

Nowadays I find chocolate and/or chocolate-based snacks to be great motivators. Everyone loves chocolate. If someone has a lot of work to do, put a piece of fudge in a glass container (so they can see it) and let them know that if they accomplish their tasks, they can eat the fudge. You'll definitely get a reaction!

For me, the favourite chapters have always been the last chapters in the books. I knew exactly how each book would end - and how the first chapter of the following book would begin. I knew I wanted to leave the readers with answers - and a bunch of new questions!

Adults, Sophie has decided a long time before, were really bad at making up good excuses.

Some writing courses will advise you to write what you know. I've always thought this is very odd advice ... because it means, for example, that I should not be writing about Nicholas Flamel, because I didn't live in France in the 15th Century, I was not an alchemyst, am not immortal (despite the rumours) and do not know magic.

When I said that I was king of forwards, you've got to understand that I don't come up with this stuff. I just forward it along. You wouldn't arrest a guy who was just passing drugs from one guy to another.

I am a great believer that all the primary research has to be done before principle writing begins. I'm a huge advocate of plotting.