The management of twenty-one children with a defect of the tibial shaft due to acute haematogenous osteomyelitis is described. Half the defects were due to removal of the sequestrum before the involucrum had formed. Only four patients, all under ten years of age, had spontaneous regeneration of the shaft. Eleven children had a posterior tibiofibular graft and six had a transfer of the ipsilateral fibular diaphysis. The results of operation were superior to those of spontaneous regeneration. All the grafts united and the children returned home to lead normal lives. Shortening was only a problem when growth plates or adjacent joints had been damaged. We now leave the sequestrum for up to one year after the onset of infection. If the involucrum fails to form we reconstruct the tibia as soon as possible after sequestrectomy.