Otumba is one of a few Late Aztec-period city-states in the Basin of Mexico whose central city or town is not obscured by post-Conquest occupation. Long-term research there began in the early 1960s, with more recent fieldwork between 1987 and 1989, and has been complemented by intensive laboratory and technical analyses that are still underway. Traditional typological analyses have been aided by neutron activation analyses providing strong evidence of economic linkages between the Otumba city-state and raw material sources, as well as evidence of tribute and market distribution channels for finished products within and outside the Otumba city-state.