Cooperative behavior has been one of the enigmas of evolutionary theory since the days of Darwin. The contributions to this book examine the many facets of cooperative behavior in primates and humans. Some of the world’s leading experts summarize and review the state of the art of theoretical and empirical studies of cooperation. This is the first attempt to bridge the gap between parallel research activities in primatology and studies of humans. This comparative approach highlights both common principles as well as aspects of human uniqueness with respect to cooperative behavior.