Aging is associated with a natural dysregulation in immune functioning which may be amplified when it occurs in the context of chronic stress. Family dementia caregiving provides an excellent model to study the impact of chronic stress on immune functioning among older individuals. Empirical data suggest that the stress of caregiving dysregulates multiple components of innate and adaptive immunity. Elderly caregivers have poorer responses to vaccines, impaired control of latent viruses, exaggerated production of inflammatory mediators and accelerated cellular aging, compared to noncaregiving older adults. The chronic stress-induced immune dysregulation observed among older caregivers appears to be of sufficient magnitude to impact health. Furthermore, evidence suggests that chronic stress leads to premature aging of the immune system.