A field biologist since 1972, Packer began his work studying primates at Gombe and then the lions of the Serengeti and the Ngorongoro Crater with his wife and colleague Anne Pusey. In this work he introduces the reader to the real world of fieldwork - initiating assistants to lion research in the Serengeti, helping a doctoral student collect data, collaborating with Jane Goodall on primate research. The study also explores the social lives of the animals and the threats to their survival. Packer grapples with questions he has tried to answer for more than two decades. Why do female lions raise their young in creches? Why do male baboons move from troop to troop while male chimps band together? How can humans and animals continue to coexist in a world of diminishing resources? Immediate demands - logistical nightmares, political upheavals, physical exhaustion - yield to the larger inescapable issues of the interdependence of the land, the animals, and the people who inhabit it.