It has been more that 40 years since Hans Kummer and his students described the unique features of hamadryas baboon social organization and proposed an ecological explanation in the initial description and understanding of the hamadryas-anubis baboon hybrid zone. Today, the richness of primatology lies in its integrative nature. The Awash project exemplifies the value of studies that incorporate both intervention (genetics, endocrinology, morphometrics, virology, neurobiology) and observation (behavior and ecology), and thus mirrors the evolution of the field of biological anthropology itself. This volume is far more than a compilation of articles on one primate population; rather, it stands as a model of how varied approaches in a number of research areas contribute to an understanding of this complex hybrid zone in a fashion that far exceeds that achievable by a single perspective alone.