Excavations at Cerro de Trincheras (2 volumes) reports the work of a collaborative bi-national effort to study the important trincheras site of Cerro de Trincheras in Sonora, Mexico. The chapters summarize and discuss artifacts and other data collected from eight months of excavation in 1995-96. The volumes evaluate the structure, organization, and role of this particular site in relation to the Hohokam and other trincheras sites. This report constitutes a significant and important contribution to the understanding of this site and the general archaeology of Sonora.