Aplastic anemia (AA), a potentially fatal disease, may be cured with marrow transplantation. Survival in pediatric patients has been excellent early after transplantation, but only limited data are available regarding late effects. This study evaluates late effects among 152 patients followed 1-38 years (median, 21.8 years). Transplantation-preparative regimes were mostly cyclophosphamide with or without antithymocyte globulin. Survival at 30 years for the acquired AA patients is 82%, and for the Fanconi anemia patients it is 58% (P = .01). Multivariate analysis demonstrated that chronic GVHD (P = .02) and Fanconi anemia (P = .03) negatively impacted survival. Two Fanconi patients and 18 acquired AA patients developed a malignancy that was fatal for 4. There was an increased incidence of thyroid function test abnormalities among those who received total body irradiation. Cyclophosphamide recipients demonstrated normal growth, basically normal development, and pregnancies with mostly normal offspring. Quality-of-life studies in adult survivors of this pediatric transplantation cohort indicated that patients were comparable with control patients except for difficulty with health and life insurance. These data indicate that the majority of long-term survivors after transplantation for AA during childhood can have a normal productive life.