Most pediatric tibia shaft fractures are amenable to nonoperative treatment with satisfying results, yet surgical stabilization is necessary in certain cases. The purpose of our study was to determine the effectiveness and the complications associated with elastic stable intramedullary nailing in severe pediatric tibial fractures. We retrospectively reviewed 24 tibia shaft fractures in 24 patients that were treated operatively by elastic stable intramedullary nailing between 1997 and 2005 at our institution. Extensive review of all charts and radiographic data was completed at Cincinnati Children's Hospital Medical Center. There were 8 closed and 16 open fractures. The average union time for all tibia fractures was 20.4 weeks. The average union time for closed and open fractures was 21.5 and 20.2 weeks, respectively. Complications include 2 (8%) neurovascular, 2 (8%) infections, 2 (8%) malunions, and 1 (4%) leg-length discrepancy. Although complications do exist, elastic stable intramedullary nailing of pediatric tibia shaft fractures using Nancy nails is an effective treatment option.