We describe 11 patients with congenital pseudarthrosis of the tibia treated by a free vascularised fibular graft (FVFG) and followed up from 10 to 64 months (mean 38). Bony union was achieved in nine of the 11 cases: two failures required amputation. The mean time for union in the successful cases was five months. Nine of the 11 patients had had an average of four surgical procedures before the FVFG, so the graft was a salvage procedure for which the only alternative was amputation. FVFG is recommended as a primary procedure for the treatment of congenital pseudarthrosis of the tibia if there is a large tibial defect (over 3 cm) or shortening of more than 5 cm. The primary use of this operation is not advised for cases in which standard orthopaedic procedures are expected to succeed. For a small defect with a favourable prognosis (Boyd and Sage 1958), we recommend conventional bone grafting, intramedullary nailing and electrical stimulation.