Each of the main approaches to catheter ablation of atrial fibrillation (AF, segmental and circumferential) is associated with limited efficacy in patients with permanent AF. The objective is to report outcomes of circumferential ablation with pulmonary vein (PV) isolation, determined using a circular mapping catheter, in patients with permanent AF and determine relations between the duration of permanent AF and efficacy. The patient population was composed of 41 consecutive patients (34 men; age 58 ± 11 years) with permanent AF who underwent radiofrequency catheter ablation through circumferential ablation with PV isolation. They were in permanent AF for 2.3 ± 3.6 years, and 3.4 ± 2.2 cardioversion procedures and 1.9 ± 0.8 class I/III antiarrhythmic drugs had failed. After a follow-up of 11 ± 2 months, the single-procedure success rate was 36% (n = 15) with an additional 12% (n = 5) showing improvement. With repeat procedures in 19%, the success rate was 54% (n = 22) with an additional 12% (n = 5) showing improvement. All patients who underwent repeat ablations had recovered PV conduction. Single-procedure success was higher in patients who were in permanent AF for ≤1 year compared with those in permanent AF for >1 year (50% vs 20%, respectively, p = 0.05). A major complication occurred in 4 patients (8%), including 3 patients with vascular complications and 1 with stroke. In conclusion, study results suggest that circumferential ablation with PV isolation has moderate efficacy in patients with permanent AF. Efficacy is limited in those in continuous AF for >12 months.