Lung cancer is the most common cause of cancer-related mortality in the USA. Surgical resection is the standard treatment for resectable disease; however, a significant percentage of patients with otherwise resectable lung cancer may have other comorbidities, precluding surgical resection. In patients with Stage I non-small-cell lung cancer, conventional external-beam radiotherapy is typically offered as treatment in medically inoperable, high-risk patients with reported 5-year survival rates of 10-30%. An emerging technology in the treatment of lung tumors is radiofrequency ablation, which is a thermal ablative technique and may be applicable in high-risk patients with lung cancer. In this article we will review the principles of radiofrequency ablation, the common devices in use, the experimental background, the results of 'ablate and resect' studies and the clinical experience with radiofrequency ablation in the treatment of lung neoplasm.