The essays in this volume were first published in 1979 and were written by specialists in different aspects of the study of pastoralism, covering all major groups of nomadic pastoralists. They show how the study of nomadic pastoralism can contribute to the understanding of the forms of human existence. The essays examine the relationships between the economic and social organization of pastoral societies and the ecological constraints to which they are subjected, discuss the factors which contribute to the emergence of social and economic inequalities within nomadic societies and analyse whether the evolution of pastoral society is a function of the contact which nomadic groups have with settled agricultural and urban societies or of the contradictions internal to pastoral societies themselves.