Abstract: What are the benefits that animals gain from living in a social group? This question has been the primary focus of the author's ecological interest. After many years of original and innovative research on the African buffalo, particularly at Lake Manyara in northern Tanzania, Herbert Prins has now summarized the results of much of this widely-respected work in this fascinating book. While advantages in reduction of the risks of predation or in increased efficiency of foraging on certain types of resources are now widely recognized, until now there has been less attention paid to the idea of the animals themselves as `information centres' and the extent to which the individual may be able to make use of information gathered by conspecifics, adjusting its own behaviour in response. Such a case-study has wide implications for research on social structure and organization in other species, and these are explored within the book. However, it is not a book aimed simply at the academic researcher, zoologist and behavioural ecologist; since it is written in a readable and accessible style, the book will also be enjoyed by wildlife enthusiasts, interested naturalists, wildlife biologists and wildlife managers.