Based on recent archaeological surveys and excavations, the chapters in this volume provide current, comprehensive, area-by-area summaries of the region's Precolumbian past. Research in the last two decades has indicated that the evolution and adaptations of the indigenous cultures of the region parallel those found elsewhere in Mesoamerica, from the simple Formative groups to the complex states of the North. The topics discussed in the book--areal and cultural syntheses and specific problems such as chronology, social organization, and economic systems--present much new information crucial to the understanding of cultural variations in Mesoamerica. Michael Foster is a senior archaeologist and senior project director for the cultural resources division at Logan Simpson Design in Tempe, Arizona. He lives in Phoenix, Arizona. Shirley Gorenstein is a professor emerita of anthropology, Rensselaer Polytechnic Institute. She lives in New York City. Phil C. Weigand, Department of Anthropology State University of New York at Stony Brook.