Atrial fibrillation is driven by spontaneous electrical activation emerging from the pulmonary veins. Catheter ablation using either radiofrequency or cryothermal energy electrically isolates these veins from the left atrium, both reducing the burden of atrial fibrillation episodes and improving the patient’s symptoms. Catheter ablation is superior to antiarryhthmic drugs when patients are carefully selected. Underlying medical problems – including obesity, hypertension and obstructive sleep apnoea – should be optimally treated before considering ablation. Although this treatment has the potential to cure patients of their symptoms, they should be aware of the important associated procedural complications.