We compared the health of 593 adult survivors of childhood and adolescent ALL treated on CCG protocols to that of 409 of their siblings. Survivors had been diagnosed between 1970 and 1987 at an average age of 10.2 years (range, 0.1-20), had survived at least 2 years, were off therapy, in remission, and were at least 18 years of age. Survivors had an average age of 23 years(range, 18-33), and controls had an average age of 25 years (range, 18-42). Overall, 442 survivors (91.5%) and 379 controls (92.7%) described their health as either good or excellent (p, ns). Survivors reported significantly more diabetes (6%), seizures (6%), paralysis (2%), stroke (1%), hypothyroidism(3%), thyroid nodules (3%), other endocrine problems (3%) and osteoporosis(3%) during their lifetime. 7 survivors reported second cancers. At follow-up, survivors reported significantly more hypertension (2.9% vs 1.0%, p=0.04) and liver problems (1.7% vs 0.3%, p=0.03). The majority of young adult survivors of ALL have good health overall, but longer follow-up is required to document whether good health continues into middle age.