We examined the effects of brief psychological stressors on cardiovascular, neuroendocrine, and cellular immune response in 22 older women to investigate the common effects of stress across systems. Results revealed that psychological stressors heightened cardiac sympathetic activation, elevated plasma catecholamine concentrations, and affected the cellular immune response (ps < 0.05). In a replication and extension, 27 women caring for a spouse with a progressive dementia (high chronic stress) and 37 controls category matched for age and family income (low chronic stress) performed the 12-min laboratory stressor. Measures were taken before (low acute stress) and immediately following (high acute stress) exposure to the laboratory stressors as well as 30 min after termination of the stressor (recovery period). Acute stress again heightened cardiac sympathetic activation, elevated plasma catecholamine concentrations, and affected cellular immune responses (ps < 0.05), whereas chronic stress was associated with higher reports of negative affect, enhanced cardiac sympathetic activation, elevated blood pressure and plasma levels of ACTH, and diminished production of interleukin-1 beta (ps < 0.05). Correlational analyses in both studies further suggested that individuals who showed the greatest stress-related changes in HPA activation also exhibited the greatest diminution in cellular immune response.