Radiofrequency thermal ablation has been accepted as a promising technique to treat unresectable liver tumors. However, any interventional procedure should be performed only if the procedure is safe, with minimal morbidity and mortality rates. Recently, three separate multicenter surveys have reported acceptable morbidity and mortality rates for a minimally invasive technique. The mortality rate ranged from 0.1% to 0.5%, the major complication rate ranged from 2.2% to 3.1%, and the minor complication rate ranged from 5% to 8.9%. The most common causes of death were sepsis and hepatic failure, and the most common complications were intraperitoneal bleeding, hepatic abscess, bile duct injury, hepatic decompensation, and grounding pad burns. Minor complications and side effects are more common than major complications, but most of them are transient and self-limiting. Several strategies for avoiding or limiting the impact of complications after radiofrequency ablation are recommended: (a) careful patient selection, (b) combined treatment with other techniques when appropriate, (c) selection of the most appropriate guiding modality and approach, and (d) early detection and appropriate management of any major complications. Knowledge of the broad spectrum of complications and relevant management enables the operator to minimize the incidence and effect of any complications that occur after radiofrequency ablation.