In 1984, an initial report was published on the use of BMT for inborn errors of metabolism. Our first BMT patient had a diagnosis of Maroteaux-Lamy syndrome. She had end-stage cardiopulmonary disease at the time of the transplant and was considered likely to die within months. (69) She is still alive 2 decades later, albeit with limited pulmonary function. In 1992, experimental data demonstrated the prevention of CNS deterioration in fucosidase-deficient dogs after BMT.70 These findings have been noted in many other similar studies. (46) Ample data indicate that BMT can reconstitute the CNS in several of these diseases. Progress is continuing in reducing the morbidity and mortality. In the near future, additional advances may allow for no loss of life and no illness during the bone marrow transplantation process. There is hope that by using neonatal screening techniques, infants at risk can have metabolic storage diseases diagnosed before the diseases progress so that effective treatment can be provided. The combination of all of these advances should result in a logarithmic improvement within the next 2 decades. The plan will be to avoid any mortality or morbidity and to always provide complete engraftment that is permanent and enters all tissues completely.