Radiofrequency (RF) ablation is one of several local treatment strategies that can be used for the destruction of a variety of primary and secondary liver tumors. As experience with RF ablation grows, it becomes increasingly evident that successful ablation requires meticulous technique. In addition, knowledge of potential complications is critical for both the interventionalist and the radiologist, whose postablation interpretation can facilitate identification of complications and treatment failures. Hepatic RF ablation offers significant advantages in that it is less invasive than surgery and carries a low risk of major complications. Successful prevention of complications and treatment failures begins at initial consultation and continues with preablation evaluation of specific patient factors such as coagulation profiles, use of medications, and risk factors for infection. Other predisposing factors include background liver cirrhosis, prior hepatectomy, and portal hypertension. During ablation, careful attention must be given to tumor size, number, and location. For large or multiple ablations, separate ablation sessions can help reduce the prevalence of postablation syndrome, and clustered electrodes and multiple overlapping treatment zones may be used to reduce the risk of treatment failure. It is critical to reevaluate tumors during ablation to determine the best approach and to compensate for changes in size and relative location due to patient positioning. With use of these strategies, hepatic RF ablation can be performed with greater safety, better patient tolerance, and a reduced risk of complications and treatment failures.