Although evidence suggests that adolescents with chronic illness are at a greater risk for psychosocial disability, little is known about the adolescent's perception of the impact of the disease on his or her day-to-day life. Standardized measures of coping strategies, mastery, self-efficacy, social support, depression, and a semistructured interview on everyday difficulties were administered to matched groups (sex and age) of 31 adolescents with cystic fibrosis, 31 adolescents with diabetes, and 31 healthy controls. No differences were found between control and adolescents with a chronic disease responses on the standardized measures. The semistructured interview, however, revealed that the adolescent's perception of his or her physical health and the reaction of other family members to the illness were important sources of stress. These findings suggest that, in general, adolescents with a chronic illness cope effectively with their disability but that parents and clinicians must be sensitive to the adolescents' feelings and concerns regarding their health and its impact on the family.