Bill Prince-Smith was a farmer and a teacher and a dentist before he became a writer of children's books at age of 60. Now, thirteen years later, he has written more than 80 books. Every day, he goes into his office and writes. In the evening, he gives the work to his wife to read. "She tells me when she doesn't like something,"says Bill. "My ten grandchildren don't live near here but they also read my stories and say if they are good or bad". And so Bill has learned what young children want to read.Bill writes about the life in his village and on the farms near it. His fifth book is his favourite: The Sheepdog is about a farmer and the dog that helps him. "I have always liked animals" says Bill, "and dogs are so clever, they learn very quickly."Last year, the book was made into a film with real animals and actors. The film-makers used the latest computer technology to make people think that the animals are speaking. Bill was very pleased with the film. "Sometimes film- makers change books, but they didn't change mine and I love the film.