David Sim was born in Glasgow in 1953. He studied graphic design at the Edinburgh College of Art and then illustration at the Royal College of Art, London, graduating in 1980. He then worked for many years in London for a wide range of clients, including magazines, design groups and advertising. He now works mainly for children's publishers, illustrating, designing and writing children's books.
Lois Rock is the author of more than twenty books for children, including "O Wonder Why", published by Chronicle Books. She lives in Oxfordshire, England.