During the past decade, catheter ablation of atrial fibrillation has been progressively used for the treatment of drug-refractory patients. As experience and technique have evolved, patient selection criteria have been modified to include a wider range of patients. Patients with paroxysmal, persistent, and longstanding persistent atrial fibrillation can be treated with catheter ablation. Catheter ablation is an option for many patients, including older patients (septuagenarians and octogenarians), those with enlarged left atrium, and those with cardiomyopathy. Results and safety are satisfactory and often superior to medical treatment. In patients with structural heart disease, multiple ablative procedures may be required to achieve cure. Ongoing clinical research will provide further insight into future criteria for patient selection.