Twenty-seven children, surviving disease-free for more than 1 year after allogeneic bone marrow transplantation (BMT) for hematological malignancy were evaluated for the long-term effects on endocrine function, sexual development, physical growth, appearance of ocular cataract and psychological sequelae. The growth rate was not decelerated in the prepubertal period in children not affected by chronic graft-versus-host (GVH) disease and without previous cranial irradiation. Development of sexual characteristics was delayed in 4 relevant cases. Thyroid function was not adversely affected, gonadal function was impaired in girls, transplanted after menarche, ocular cataract developed in all cases, irradiated without shielding of the eyes after 4 years. Psychologically, children after BMT had an advantageous social development.