Over the ages, humans have always been fasci- manner and to present a comprehensive and nated by dolphins. This fascination heightened in organized treatise on the subject. In my opinion, the 1950s when oceanariums and aquariums such an effort is long overdue, since there is a paucity of books on this subject. I know of only began to use dolphins as show performers to one booklet and one book dealing with echoloca- demonstrate their prowess and display how tractable and trainable they were. The televi- tion in dolphins. I have attempted to introduce as many concepts from physics as possible sion series "Flipper" brought considerable public awareness and, coupled with the growing sophis- and also to create mathematical models as an aid to the quantification and understanding of tication and popularity of dolphin shows, helped to further heighten public interest in these intri- biosonar capabilities. Topics are covered which guing marine mammals. Soon the alluring but range from auditory pathways and processes, to anatomy of the dolphin's head, to signal pro- unfounded myth began to surface that dolphins cessing models, to a comparison of the sonar of are the smartest of animals, with an intelligence approaching and perhaps surpassing that of bats and dolphins. humans.