We report on two patients with spastic quadriplegia and three patients with spastic diplegia who underwent selective posterior rhizotomy. The mean period of follow-up was 15 months (range, 12-21 months). The patients were assessed preoperatively and at 2 weeks, 3 months, 6 months, and 1 year after surgery. Tests included those for muscle tone (using a modified Ashworth scale), range of passive movement, functional status, and gait pattern. Muscle tone was reduced substantially after the procedure, and the range of passive movement was increased. Both the dependent and independent ambulators showed an increment in their walking velocity and stride length. There were no postoperative complications apart from mild fever and the treatment was well tolerated by both patients and parents. There was no return of spasticity in any of the patients during follow-up. The reduced spasticity resulted in better motor performance, and patients felt more comfortable with their daily activities. We conclude that selective posterior rhizotomy should be considered for those patients who have cerebral palsy and are disabled by spasticity.