An Investigation of Mental, Physical, and Sleep Health: The Role of Social Determinants Summary Sleep deficiency is an important public health concern and is known to significantly impact mental and physical health. Sleep deficiency is an essential risk factor and marker for chronic conditions that disproportionately affect racial/ethnic minority populations and further contribute to health disparities. Social determinants of health are considered a system of schemes providing an understanding of how health is socially patterned, investigating causal pathways between social conditions and human health and disease. Noticeably, sleep deficiencies seem to share similar determinants and causal pathways observed for health outcomes with well-known health disparities. Limited studies have investigated whether social-environmental mechanisms and pathways that result in health disparities for mental and physical health outcomes can explain sleep deficiencies. This study will investigate the relative contribution of social-environmental factors at the individual (e.g., biological vulnerability to elevated blood pressure), interpersonal (e.g., city stress), community (e.g., neighborhood characteristics), and societal (e.g., societal structure, discrimination) levels and their influence as mechanisms to understand sleep deficiencies impact on mental and physical health, thus enabling us to substantiate key drivers of health disparities for racial/ethnic minorities. An understanding of the critical role of sleep deficiencies at the interplay of upstream social-environmental influences and downstream mental and physical health outcomes will be instrumental in moving the field toward a more useful integration of behavioral, biological, physiological, and socio-environmental understanding, which may lead to culturally tailored interventions to reduce the societal burden of health disparities.