Sally was a theatre designer and specialised in costume for fifteen years before moving into children's books. Sally lives in London and works full-time as an illustrator and writer.

Polly's Running Away Book was her first book for Bloomsbury, although she has been very successfully published by Orion Children's Books, where she is notably the illustrator of Jostein Gaarder's novels as well as the creator of beautiful colour picture books. She is the author of the Tales from the Box which is a series of books about a box of toys and their adventures. The first two books are called The Countess's Calamity and Boolar's Big Day Out.