Twenty-three children had proportionate growth of bone and soft tissue between two and eleven years after a Syme ankle disarticulation. All walked with permanent prostheses within three months after operation. Ischemic necrosis occurred twice after inadvertent ligation of the posterior tibial artery. Suture of the extensor tendons into the heel pad eliminated its posterior migration. Prosthetic realignment compensated for progressive genu valgum in ten of fourteen amputees with fibular hemimelia. On the basis of these gratifying results, the Syme ankle disarticulation is suggested as early treatment for certain congenital anomalies of the lower extremity.