Summary The study of stress and aging are closely aligned. Exposure and reactivity to stressors to these stress hormones leads to accumulated wear and tear on the body, referred to as “allostatic load,” which in turn contributes to an increased risk of cognitive impairment, illness, and mortality. In this chapter we provide a broad framework for incorporating the role of stress into the study of health and aging by describing: (1) concepts and measurement of stress processes, (2) life-span and life course perspectives on stressors and their consequences, (3) biomarkers that provide a link between stressors and health, and (4) emerging research documenting the effects of stress on cognitive health. Suggestions for future research include taking multidimensional assessments of change in life events, chronic stressors, and daily hassles in combination of subjective and biological indicators of health and well-being.