Thermal ablation strategies, including the use of radiofrequency, microwaves, lasers, and high-intensity focused ultrasound, are gaining increasing attention as an alternative to standard surgical therapies in the treatment of primary hepatocellular carcinoma. Benefits over surgical resection include the anticipated reduction in morbidity and mortality, low cost, suitability for real-time imaging guidance, ability to perform ablative procedures on an outpatient basis, and the potential application in a wider spectrum of patients-including those who are not surgical candidates. In this review, the authors examine the reported clinical success of each of these four therapies, potential complications, current limitations, and future directions of development.