Behavioral medicine research from across the globe has been catalyzed by the quest to understand the interactions between psychological, social, and physiological factors underlying disparities in human health. A more complete biopsychosocial model increasingly integrates advanced clinical and laboratory assessments of relevant environmental chemicals, biological mediators of inflammation, cardiometabolic and endocrine markers, infectious disease exposure, and genetic polymorphisms determined from saliva specimens. The overarching aims are to identify mechanisms, decode moderating processes that translate adversity into risk, and verify the impact of clinical intervention. This special issue of the International Journal of Behavioral Medicine highlights novel contributions of salivary bioscience with emphasis on research utilizing varied research designs (i.e., experimental, longitudinal, dyadic), incorporating a broad array of salivary analytes, and investigating the influence of psychological and social factors on human health.