Compared to terrestrial mammals, the cetacean skin has some unique features. It is not only non-glandular and essentially hairless because of the missing hair follicle complexes, except for sinus hairs in the head region, but shows very specific adaptations to the aquatic environment to overcome problems arising from the saltwater milieu and its low temperatures, or from any biofouling attacks. Moreover, the environmental factors impinging upon the cetacean integument, and necessitating their perception, correlation and a response, are – rather unusual for former terrestrial mammals – also water turbulence and pressure, and light or its reflection. This new book examines the integumentary system of the dolphin which protects it from possible damage that could arise because of their aquatic environment.