The authors examined the relationship among psychosocial vulnerability (stress) and resilience (adaptive potential) factors and three outcome measures, self-reported physical symptoms, positive and negative affect, and natural killer cell activity in 39 male and female older adults residing in a retirement community (mean age = 73.5). Although life events were directly related to physical health symptoms, both perceived stress and adaptive potential were significantly associated with positive and negative affect. There was a tendency for adaptive potential to buffer the effect of perceived stress on negative affect. However, natural killer cell activity was not significantly related to any psychosocial vulnerability and resilience factors in this small sample. Implications for studying the effects of stress on health in older adults are discussed.