Most of the discussion about degradation in the development literature focuses on biological and climatic factors, but there is also a resurgent awareness of the pertinence of socioeconomic and political processes. Specialists from both natural and social sciences are contributing to the discussion, although as yet an ecological perspective drawing on both has rarely informed the policies and actions of governments and aid agencies. Historical materialists illuminated for anthropology the critical relationship between technologies and the social organization of production, and the ways in which local organizations were articulated with larger regional, national, and world political economies. The editors of this volume have their major field experiences in research on pastoral production systems in semiarid rangelands of East and West Africa. In selecting conference participants, emphasis was given to persons who had conducted long-term fieldwork in an area identified as experiencing or risking environmental degradation. The chapter also presents an overview of the key concepts discussed in this book.