Chris Grabenstein is an American author of children's and young adult fiction. He is best known for his New York Times bestselling series, The Island of Dr. Libris, Escape from Mr. Lemoncello's Library, and the Riley Mack books. He has also written several stand-alone novels, including the Edgar Award-winning Welcome to Wonderland series. Grabenstein is a former advertising executive and has written for television, including the Emmy-winning show, Sesame Street. He is a graduate of the University of Tennessee and lives in New York City with his wife and two children.