Twenty-four children with spastic equinovarus deformity due to cerebral palsy were treated by anterior transfer of the posterior tibial tendon and Achilles tendon lengthening. In five patients, the operation was performed on both sides, making a total of 29 feet available for evaluation after an average follow-up of five years. Only 38 per cent of the results were graded "good" or "satisfactory." Sixty-two per cent were rated as "poor" because of valgus, calcaneus or equinus deformity severe enough to require re-operation. The post-operative deformity was generally evident one or more years after surgery, often progressive, and more disabling as well as more difficult to correct than the original condition. Although the percentage of acceptable results was considerably higher for hemiplegic patients than for others in the study, we conclude that in this group and in all other categories of spastic patients anterior transfer of the posterior tibial tendon should not be performed.