Jon Klassen has written and illustrated three books—I Want My Hat Back (Candlewick, 2011), This Is Not My Hat (Candlewick, 2012), which won the Caldecott Medal, and We Found a Hat (Candlewick, 2016). He has also illustrated numerous books by other authors, including six by Mac Barnett. Before making books, he worked as a set designer for animated feature films. He lives in Los Angeles but is originally from Ontario, Canada.