The problems in infected nonunion include multiple sinuses, osteomyelitis, bone and soft tissue loss, osteopenia, adjacent joint stiffness, complex deformities, limb-length inequalities, and multidrug-resistant polybacterial infection. Bone gap and active infection are the crucial factors relating to treatment and prognosis. Gaps larger than 4 cm likely cannot be effectively bridged by corticocancellous bone grafting. If the limb has intact distal circulation and sensation, limb salvage and reconstruction generally is preferable to amputation. The fracture generally unites if adequate debridement of the nonunion site is done with fracture stabilization and bone grafting. We reviewed 42 consecutive patients with infected nonunion of the long bones. These patients have been categorized into two groups. Type A is infected nonunion of long bones with nondraining (quiescent) infection, with or without implant in situ; Type B is infected nonunion of long bones with draining (active) infection. Both are classified further into two subtypes: 1) nonunion with a bone gap smaller than 4 cm or 2) nonunion with a bone gap larger than 4 cm. Single-stage debridement and bone grafting with fracture stabilization are the methods of choice for Type A1 infected nonunions. Adequate debridement, fracture stabilization, and second-stage bone grafting gives desirable results in Type B1 infected nonunions. Distraction histiogenesis is the preferred procedure for Type A2 and B2. The autogenous nonvascularized fibular graft, posterolateral bone grafting for the tibia, and centralization of the ulna over distal radial remnant (single bone forearm) may be good treatment options in selected cases.