This volume presents the analyses and interpretation of a wide range of human osteological and burial data. The Petexbatun bioarchaeology subproject included a complete assessment of burial practices and human osteology in the Petexbatun sites and in the Pasion region at large. The chapters on paleopathology explore the human skeletal evidence for childhood nutrition and ill health throughout the various sites and the inter-site areas of the Petexbatun region, as well as from Seibal and Altar de Sacrificios. Wright's innovative study goes on to apply the most recent chemical techniques, particularly isotopic and elemental analyses of human bones, to assess the ancient diet of the populations of the Pasion region. Variability between sites, across social status groups, and over time is evaluated and conservatively interpreted in the light of contemporary issues and problems of bioarchaeological methodology and interpretation. Wright uses the new Petexbatun and Pasion region osteological results in order to re-examine past and current work on skeletal remains from other regions of the ancient Maya lowlands. In the final chapters of this work, Wright's osteological analyses inform a critique of the role that bioarchaeological data have played in the development of current ideas regarding the role of ecology, diet, nutrition, disease, invasion, and other factors in the demise of Classic Period Lowland Maya society. For bioarchaeologists, this work sets a new standard in the breadth and depth of osteological study, and its integration with problem-oriented archaeological research. For Pre-Columbian scholars in general, it provides new insights into the environmental and biological issues central to the debate on the end of the Classic period of Maya civilization.