MRI scans of the brain and spinal cord, together with neurological and urological assessments, were carried out on 20 young people (aged between eight and 22 years) who had had surgical treatment of spina bifida in early life and in whom there had been no deterioration of spinal cord function. 19 were imaged successfully. The cord was tethered in all and it was low-lying in 18. Five had cavities within the cord; other abnormalities included cord thinning, lipomas and diastematomyelia. The relationship of these findings to subsequent deterioration and the use of MRI in these patients are discussed. These abnormalities, found in the absence of clinical deterioration, throw fresh light on the natural history of this condition.