Twenty children with acute type III open fractures of the tibial metaphyses or diaphysis were retrospectively studied. The average age was 9 years, 1 month (range, 2 years, 11 months to 16 years, 2 months). There were seven type IIIA fractures, 10 type IIIB fractures, and 3 type IIIC fractures. All fractures were irrigated and debrided, and prophylactic antibiotics were given for a minimum of 48 h. Fifteen fractures were initially treated with external fixation, three with casts, one with internal fixation, and one with a combination of external fixation and limited internal fixation. Free muscle flaps were used for soft-tissue coverage in six patients, and a local muscle flap in one patient. The average time to fracture healing was 29 weeks, and the median time to fracture healing was 20 weeks (range, 8-104). Four patients had delayed union, and two additional patients had nonunion. Both patients with nonunion were successfully treated with autologous bone grafting. The time to fracture union was related to the severity of soft-tissue injury, fracture configuration, segmental bone loss, and infection. Osteomyelitis developed in three patients. All were successfully treated. Two patients treated with external fixation had leg-length discrepancies of > 1 cm, with the injured extremity longer in both cases. There were no late amputations. Children with severe open fractures of the tibia have a good prognosis for limb salvage with aggressive wound care and fracture management.