1. The results of posterior spinal fusion for paralytic scoliosis in 118 patients have been reviewed after growth had finished. The criteria for skeletal maturity were both clinical and radiological, with emphasis on ossification of the iliac apophyses. 2. The age of onset of anterior poliomyelitis and the age at which scoliosis was first noticed, as well as the extent of the muscle weakness and the curve patterns, all have a bearing on the severity of the deformity and the indication for operative treatment. 3. The method of treatment including operation is described and the complications detailed. The use of a tibial strut has now been abandoned and Harrington instrumentation has become routine. 4. There were five deaths in the series, three early and two late. 5. The difference in height, changes in respiratory function and eventual functional capacity have been analysed.