Marilyn A. Masson, professor of anthropology at the University at Albany, State University of New York, is coauthor of Kukulcan's Realm: Urban Life at Ancient Mayapán. David A. Freidel, professor of anthropology at Washington University in St. Louis, is coeditor of Maya E Groups: Calendars, Astronomy, and Urbanism in the Early Lowlands. Arthur A. Demarest is Ingram Professor of Anthropology at Vanderbilt University and director of the Vanderbilt Institute of Mesoamerican Archaeology and Development. He is the author of Ancient Maya: The Rise and Fall of a Rainforest Civilization.