A total of 39 fractures of the diaphyses of long bones in 31 children were subjected to operative fixation. Indications for surgery included concomitant severe head injury, multiple injuries, patients nearing skeletal maturity, inability to obtain a satisfactory reduction by conservative means, severe soft-tissue injury with or without vascular trauma, long-standing neurological disorder with incapacity and contractures, malunion, and delayed union. Although long-bone diaphyseal fractures in children are generally managed non-operatively, the use of fixation may be indicated in certain cases.