A consecutive series of 53 children with myelomeningocele (mean age 7.6, range 3.2 to 11.4 years) was assessed in order to see if the children with motor paresis of the lower limbs achieved the expected level of ambulation, and if not, to identify possible causative factors. Methods used were clinical examination of orthopaedic and neurological status, information from medical reports, and documentation of orthoses use. Functional skills were documented and energy expenditure was examined. Thirty-one of 53 children had reached the expected ambulation considered possible according to their motor paresis, whereas 22 of the 53 performed worse than expected. Balance disturbances, occurrence of spasticity in knee and hip joints, and number of shunt revisions made differed significantly between the groups that achieved and did not achieve expected ambulation. Functional skills of mobility differed significantly between two muscle-function levels in children who had walking ability. Energy expenditure was higher in the non-achieving group than in the group who achieved expected ambulation in each of the muscle-function levels. Results show that children with similar muscle paresis exhibit different ambulatory function. This indicates the importance of a close analysis of other factors which may cause ambulation to deteriorate in order to predict future ambulation in children with myelomeningocele.