Cultural behavior exhibits many of the features of complex adaptive systems, but is in some ways distinctive. Cultural complexity is enigmatic, improbable, and difficult to maintain. It constrains behavior, limits understanding of processes, and imposes economic burdens. The advantages of complexity are modified by human cognition and limited by economic and environmental costs. This book explores in detail how and why prehistoric Southwestern societies changed in complexity, and thus offers important new perspectives on the evolution of culture.The papers discuss the factors that made prehistoric Southwesterners vulnerable to an arid environment, and their strategies to lessen risk and stress. The topics of the book link Southwestern data to fields such as economics, climatology, and evolutionary theory. In addition to a readership of archaeologists and anthropologists, this volume will be of interest to specialists in these related fields and to those concerned with complex adaptive systems and the work of the Santa Fe Institute.