In this review, the authors examine the earliest states in Mesoamerica and how they developed. They present a definition of the state and explain why first-generation or primary states have special significance in anthropology and archaeology; they also discuss how anthropological archaeologists can detect the emergence of state organization in the archaeological record. The authors review the archaeological data bearing on early state formation in Oaxaca, the Southern Gulf Coast, the Southeastern Lowlands, and the Basin of Mexico. Although it is acknowledged that more data are needed from all regions, the authors conclude that Oaxaca currently provides the most compelling evidence of primary state formation in Mesoamerica.