Sir Quentin Blake's association with Roald Dahl began with a handshake in a publisher's office, after half a dozen of Dahl's novels had already been published and illustrated by other persons in the UK. The author rejected the first two sets of images for the book because there weren't enough of them. He then asked Blake to come up with some more pictures for it. They became friends after that, and Blake went on to illustrate several more of Dahl's books, including some written under the pseudonym Michael Bond. Blake died in January 2010 at the age of 96. He is best known for his illustrations to children's books, but he also wrote three children's books himself. They are called "The Enchanted Paintbox", "The Great Escape" and "George's Marvels". You can see all of Blake's paintings here: http://www.quentincblake.com/portfolio-full/