Long-lived, slow to reproduce, and often hidden beneath the water's surface, whales and dolphins (cetaceans) have remained elusive subjects for scientific study even though they have fascinated humans for centuries. Until recently, much of what we knew about cetaceans came from commercial sources such as whalers and trainers for dolphin acts. Innovative research methods and persistent efforts, however, have begun to penetrate the depths to reveal tantalizing glimpses of the lives of these mammals in their natural habitats. This book presents a comprehensive synthesis and review of these studies. Groups of chapters focus on the history of cetacean behavioural research and methodology; state-of-the-art reviews of information on four of the most-studied species: bottlenose dolphins, killer whales, sperm whales and humpback whales; and summaries of major topics, including group living, male and female reproductive strategies, communication, and conservation drawn from comparative research on a wide range of species. Written by cetacean scientists, this volume should be of benefit to students of cetology and researchers in other areas of behavioral and conservation ecology, as well as anyone with a serious interest in the world of whales and dolphins.