This article examines the relationship between incarceration and health functioning. Using data from the National Longitudinal Survey of Youth, the relationship between incarceration and more than 20 different measures of health are tested. Using multiple analytic procedures, a distinctive pattern of association emerges. Individuals with a history of incarceration appear consistently more likely to be afflicted with infectious disease and other illnesses associated with stress. In contrast, no consistent relationships were observed between incarceration status and ailments unrelated to stress or infectious disease. The results suggest that exposure to infectious disease and stress are important to understanding the lasting impact of incarceration on health.