This study examined daily stressors in adults ages 18 to 89 years (M = 49.6 years) over 30 days. We examined the role of individual factors (i.e., age, self-concept differentiation [SCD], perceived control) in physical and psychological reactivity to interpersonal, network, home, and health stressors. Findings were consistent with the perspective that adults were less reactive to stress on days during which they felt in control and that younger adults and adults with high SCD were more vulnerable to stress. Age, SCD, and daily perceived control, however, interacted with one another, and findings varied by stressor type. For example, age differences in reactivity were moderated by SCD whereby older adults with low SCD were particularly resilient to home stressors. In addition, whether perceived control buffered adults' reactivity to daily stress varied by age and SCD. For example, only adults with high SCD were psychologically reactive to network stressors and this was the case only on days during which they reported experiencing low control. The findings emphasize the importance of considering the varying ways in which individual characteristics interact to influence stress reactivity to different types of stressors.