Southwestern archaeologists have long recognized that platform mounds required a considerable amount of labor and organizational skill to build. Attempts to specify these behavioral dimensions have generally met with failure, however, either due to a lack of data or because researchers have been unable to place mound construction within a larger social context. Recent excavations at the Meddler Point site in central Arizona provide important new data for addressing these issues. In this article, the material and labor costs involved in building the Meddler Point platform mound are considered. The implications of these figures for understanding Classic period social organization at the site are then examined.