His research focuses on the emergence of complexity in the Maya region. He is author of The First Maya Civilization: Ritual and Power before the Classic period. (Routledge 2011). Most recently, he and his collaborators have published studies on long-term human-environment interaction and on the rise of regional states in the Late Classic period. He directs the Holmul Archaeological Project and is co-founder of the Maya Archaeology Initiative, a non-profit that supports heritage education in Guatemala.