The technique for treating nonunion of the tibia by means of electricity delivered to the site by percutaneously inserted electrodes is described. Of 131 tibial nonunions so treated with constant direct current for 12 weeks, 107 (81.7%) achieved solid bony union. Analysis of the 24 failures in the series indicated that eight of the patients did not receive adequate electricity. Of the 123 patients who did receive adequate electrical treatment (four cathodes each delivering 20 microamperes continuously for 12 weeks), 107 (87%) achieved bony union. The presence of previous osteomyelitis at the fracture site or the presence of previously inserted metallic fixation devices did not effect the end result heal rate. Comparison of the rate of union reported in this study to rates of union reported in the literature for bone graft surgery reveal no statistically significant differences in the results achieved by the two methods. Since the risk/benefit ratio is lower for direct current treatment of nonunion than that associated with conventional bone graft surgery, it is concluded that the electrical treatment of nonunion promises to become the preferred method of treatment for that condition.