Radiofrequency catheter ablation techniques allow for safe and highly effective curative therapy of a variety of cardiac dysrhythmias. The technique involves the delivery of a high-frequency, alternating electrical current through an intravascular catheter to sites of arrhythmogenic myocardium. This current induces resistive electrical heating of the tissue, resulting in discrete areas of myocardial destruction through coagulation and desiccation. Dysrhythmias most commonly treated with these techniques are atrioventricular nodal reentry and tachycardias related to accessory atrioventricular bypass tracts. For these dysrhythmias, success rates of 90% to 95% are achievable with a low (2% to 4%) risk of complications. Radiofrequency catheter ablation techniques also have been used to treat ventricular tachycardias, atrial flutter, ectopic atrial tachycardia, and sinus node reentry, albeit with lower success rates. These techniques are still evolving, alternate energy sources (such as microwave and laser) and improved catheter technology should enhance the technique's safety and efficacy for a wider range of dysrhythmias.