MARY NORTON (1903-1992) lived in England, where she was an actress, playwright, and award-winning author. As a child she created a make-believe world in which tiny people inhabited the hedgerows, living their lives out of the sight of humans. It's from this private fantasy that her most well-known books, those about the Borrowers, came about. LEONARD S. MARCUS is a well respected critic and historian of children's literature. His many books include "Dear Genius: The Letters of Ursula Nordstrom and "Margaret Wise Brown: Awakened by the Moon. He lives in New York.