In this volume, Nick Chapin presents his investigation of the sites investigated by Cynthia Irwin-Williams between 1966 and 1973 and again in the early 1980s as part of the Anasazi Origins Project in northwestern New Mexico. Her primary goal was to determine the cultural and temporal history of use in that region by Archaic hunter-gatherers, with a focus on subsistence, technology, and demography. She defined this as the Oshara Tradition, but regrettably, she never completed a final report on her research. Nick devoted several years of research into the collections and archival records she amassed. This monograph presents an up-to-date synthesis of that research, framed in contemporary theoretical and methodological terms. He describes the present and past environmental setting of the project area, reviews the investigated sites, provides a statistically-based typology of the various dart point styles recovered from these and other Archaic sites, and offers a detailed treatment of one of the most important sites, Collier Dune. He concludes by situating the Oshara Tradition in a region-wide context, underscoring its importance and continuing relevance for contemporary Archaic period research in the Southwest.