This document describes the technique of radiofrequency ablation for atrioventricular nodal reentrant tachycardia (AVNRT). It discusses catheter positioning between the coronary sinus os and tricuspid valve for ablation. The areas targeted for slow and fast pathway ablation are shown. Progression of ablation sites from the coronary sinus os inferiorly and superiorly on the septum are presented. Acceptable ablation areas between the His catheter and roof of the coronary sinus are outlined to minimize heart block risks. A case of successful AVNRT ablation in a 73-year old woman is then presented, demonstrating induction of the arrhythmia and pace mapping to identify the slow pathway for ablation.