Joan Delano Aiken (4 September 1924 – 4 January 2004) was an English writer specialising in supernatural fiction and children's alternative history novels. In 1999 she was awarded an MBE for her services to children's literature. For The Whispering Mountain, published by Jonathan Cape in 1968, she won the Guardian Children's Fiction Prize, a once-in-a-lifetime book award judged by a panel of British children's writers, and she was a commended runner-up for the Carnegie Medal from the Library Association, recognising the year's best children's book by a British writer. She won an Edgar Allan Poe Award (1972) for Night Fall.