In this interesting book, Llewellyn, a lecturer in humanities at the University of Massachusetts, presents a reader-friendly answer couched in evolutionary theory to the question at hand. In a dozen well-constructed, research-based chapters, Llewellyn makes the case that dreams help people not only remember but also decide, predict, and create. If a person could read only one book about dreams, Llewellyn's text would be this reviewer's choice.