Judith Viorst is the author of the beloved Alexander and the Terrible, Horrible, No Good, Very Bad Day, which has sold some four million copies; the Lulu books, including Lulu and the Brontosaurus; the New York Times bestseller Necessary Losses; four musicals; and poetry for children and adults. Her most recent books of poetry include What Are You Glad About? What Are You Mad About? and Nearing Ninety. She lives in Washington, DC.

Hilary Knight, son of artist-writers Clayton Knight and Katharine Sturges, was educated at the Art Students League, where he studied with Reginald Marsh. Besides the Eloise books, Hilary Knight has illustrated more than fifty books for children, six of which he wrote himself. He lives and works in New York City, not far from The Plaza Hotel.