Over the past 5 years, catheter ablation of atrial fibrillation (AF) has evolved from an experimental procedure to one that is now performed throughout the world. The rapid and widespread acceptance of this procedure reflects encouraging reports of the safety and efficacy of catheter ablation of AF. The improved outcomes of catheter ablation of AF have resulted from a combination of increasing clinical experience, but also several important technological advances. One of the most important of these has been the development and widespread utilization of three dimensional mapping systems during AF ablation The purpose of this article is to briefly review the current status and clinical role of three dimensional mapping systems in catheter ablation of AF.