This volume presents a comprehensive review of the current research in the field of primate thinking, learning and behavioural development. Recent theories of the ways in which primates perceive their world are integrated with the ways that they behave and communicate about each other and their environment. Many different species in both the wild and in captivity are discussed with coverage from the social development of neonates to the behaviour of adults. The common theme to the contributions is an attempt to understand how primates perceive, learn about and manipulate their social and physical environment.