Sociality, Hierarchy, Health: Comparative Biodemography is a collection of papers that examine cross-species comparisons of social environments with a focus on social behaviors along with social hierarchies and connections, to examine their effects on health, longevity, and life histories. This report covers a broad spectrum of nonhuman animals, exploring a variety of measures of position in social hierarchies and social networks, drawing links among these factors to health outcomes and trajectories, and comparing them to those in humans. Sociality, Hierarchy, Health revisits both the theoretical underpinnings of biodemography and the empirical findings that have emerged over the past two decades.