Illnesses were found to be primarily noncontagious and involved verifiable complaints. There was also evidence of elevated catecholamine levels in dormitory residents, possibly an indicator of increased stress. Background factors associated with greater inmate sensitivity to dormitory living were somewhat higher socioeconomic and educational levels, coming from a town of greater than 30,000 population, growing up in a home with 5 or fewer residents, extensive prison experience, and high intelligence. These results suggest that some inmates are able to tolerate crowding while others are not, and that the degree of tolerance may be dependent on prior experiences. Results further provide strong support for previous conclusions that prison dormitory housing is stressful and has a negative impact on health. Theoretical implications are developed, and it is suggested that the conventional model of crowding or environmental stress be broadened to account for the complexity of the environmental and social stressors experienced in prison.