Patricia Reilly Giff was an American author and teacher born in Brooklyn, New York, United States. She was educated at Marymount Manhattan College, where she was awarded a B.A. degree, and St. John's University, where she earned an M.A., as well as Hofstra University, where she received a Professional Diploma in Reading and a Doctorate of Humane Letters.

After spending approximately two decades as a full-time teacher, she began writing, specializing in children's literature. Giff resided in Trumbull, Connecticut, with her husband Jim and their three children. Her writing workshops have influenced other children's authors, such as Tony Abbott and Elise Broach.

She was honored with awards such as the Newbery Honor, ALA Best Book For Young Adults, and the Christopher Award. Unfortunately, she passed away due to cancer on June 22, 2021.