Norman Yoffee is Professor of Mesopotamian Studies and Anthropology at the Centre for Middle Eastern and North African Studies at the University of Michigan, Ann Arbor. His various publications and edited works include Archaeological Theory: Who Sets the Agenda? (0521440149 HB; 0521449588 PB) and The Collapse of Ancient States and Civilizations (co-editor with George L. Cowgill) (University of Arizona Press, 1988).