Chronological changes in the neurological manifestations of spina bifida are well recognized in the early developmental periods: fetal, neonatal, infantile, pre-school and school life. However, little has been written about the medical and medico-social problems of spina bifida patients in adulthood. Patients now in this age group had the condition diagnosed and managed in an era when modern neurosurgical concepts were only just beginning to be established with the aid of invasive methodology. In our series of 141 cases of spina bifida, 18 patients (13.5%) were over 16 years of age. These included 9 cases each of spina bifida aperta (myeloschisis) and spina bifida occulta (spinal lipoma). The ages ranged from 16 to 47 years (mean: 23.5 years) in the former and from 16 to 57 years (mean: 29.2 years) in the latter group. During the long-term follow-up with quantitative analysis of the spinal neurological changes using the spina bifida neurological scale (SBNS), the final outcomes appeared very grave. Except for 1 case in each group-1 grade III in the spina bifida aperta group and 1 grade II in the spina bifida occulta group-all patients over the age of 27 years were classed as having grade IV disease. There were 2 patients with spina bifida aperta in whom postoperative paraplegia appeared after delayed radical repair (at the ages of 3 years and 18 years) and 3 patients with spina bifida occulta in whom obvious neurological deterioration was observed as the natural history with ongoing paraparesis at the spinal level or late onset of sexual problems. The other group included 2 patients with spinal lipoma in whom late neurological deterioration was observed and who were obliged to undergo a second operation in spite of aggressive early procedures performed during infancy. Among the patients with spina bifida aperta, 2 had marked ventriculomegaly as a form of long-standing overt ventriculomegaly in the adult (LOVA). After the CSF shunt procedure both these patients had problems with delicate shunt dependence and requested fine shunt flow regulation. Two patients in this group also suffered from severe depression. This study involves a limited number of patients, but it may be useful for reference on various points: (1) future prospects for the management of pediatric cases of spina bifida as practiced in the majority of hospitals; (2) natural histories of untreated cases and surgical indications for preventive procedure in spinal lipoma in early infancy; and (3) internationally differing levels of management of spina bifida and the historical development of individual countries' approaches to the problems.