Delayed union of the tibia represents a diverse group of clinical problems that can at times be challenging for even the most experienced surgeon to treat. Early recognition and treatment can help patients avoid prolonged periods of pain and disability. Many factors have been associated with delayed union or nonunion; most of these factors are dictated by the injury and patient factors but others are within the surgeon's control. Although high rates of union are obtained in many series of tibial fractures using simple treatment methods, nonunion is seen by all practitioners treating tibial fractures. Early intervention to prevent nonunion seems to be in the best interest of patients and surgeons. Treatment must take into account the biologic and mechanical factors contributing to delay in fracture union.