The development of radiofrequency catheter ablation has dramatically changed the therapeutic approach of cardiac arrhythmias. All atrial rhythm disturbances are now amenable to ablative strategy. Ablation has become the first-line therapy for atrial flutter. Atrial fibrillation, a major factor of morbidity and mortality, is now a target for this radical treatment. Ablation of pulmonary vein foci, eventually associated to atrial linear lesions, raises the possibility of suppressing atrial fibrillation. The success rate is now as high as 70 to 85%, depending on the form of atrial fibrillation. For atrioventricular reentrant tachycardia either nodal or over an accessory pathway, ablation is the reference treatment with success rates of 99%. All symptomatic Wolff-Parkinson-White syndromes can be definitely cured by this technique. At the ventricular level, the procedures are often more complexes, due to advanced cardiomyopathy. However, most of sustained ventricular tachycardias can be cured by ablation. The success rates are somewhat lower (about 80%). The challenge for the next years is ablation of premature ventricular beats initiating ventricular fibrillation. The technique is also improving from day-to-day (88% success rate) and makes rise the hope of curing sudden death.