Justin Gregg weighs up the claims made about dolphin intelligence and separates scientific fact from fiction. He presents the results of the latest research in animal behaviour, and puts our knowledge about them into perspective with comparisons to scientific studies of other animals, especially the crow family and great apes. He gives fascinating accounts of the challenges of testing what an animal with flippers and no facial expressions might actually be thinking. Gregg's evidence-based approach creates a comprehensive and up-to-date study of this fascinating animal which will appeal to all those intrigued by dolphin behaviour.