This issue's Special Section features a group of articles on the recent research of the Proyecto Arqueológico Tlajinga Teotihuacan (PATT), codirected by David Carballo, to whom we extend our thanks for organizing and coordinating the Section. As the papers presented here clearly indicate, this multidisciplinary, international project, which began in 2012, has brought a wealth of new information to light on this most intriguing, non-elite district of the great city of Teotihuacan.

Until the results of the PATT began circulating in recent years, any mention of Tlajinga referred to “Tlajinga 33” or apartment compound 33:S3W1, investigated by a project of the Pennsylvania State University in the 1980s under the direction of the late William T. Sanders, with excavations and analyses directed by Deborah Nichols, James Sheehy, Rebecca Storey, and Randolph Widmer. Through their efforts, we gained new and different perspectives on irrigation, craft specialization, economic production and consumption, diet, nutrition, and disease, and how these activities and factors affected residential compound organization, status, and social stratification.

The PATT research builds on and extends this earlier work, and it has now added four additional excavation loci in the Tlajinga barrio. As Carballo states in his introduction to the Section, the primary focus of all the Tlajinga archaeology is on the working-class occupants of the compounds and their relationships to the elites who resided in the palaces and high-status residential compounds closer to the city center. Unlike the residential compounds of La Ventilla, Teopancazco, Tepantitla, Xolalpan, Yayahuala, and Zacuala—located a short distance from the epicenter of the urban core—Tlajinga was a peripheral district, presumably inhabited by relatively impoverished people, and therein lies its fascination.

The poor-quality architecture of Tlajinga apartment compounds appears to conform to expectations, but urban planning here was clearly linked to the uniform, orthogonal plan of the city as a whole. In the realm of portable material culture, Tlajinga residents apparently were not living on the edge. The domestic economy featured large-scale production of obsidian implements and a lapidary industry that depended on the acquisition of exotic raw materials such as greenstone, mica, and shell. Several high-value ritual objects, such as a stone mask and a stucco-painted tripod bowl, defy expectations of a marginalized population. Although they lived in the far southern sector of the city, more than two kilometers from the Pyramid of the Sun, the residents of the Tlajinga district appear to have been closely integrated into the Teotihuacan city-state and its region in economic, social, political, and religious practice. This is only one of many important conclusions drawn by Carballo and colleagues in these valuable contributions.