Atrial fibrillation, the most common of all sustained cardiac arrhythmias, can be cured using extensive surgical atriotomies. Experimental studies using linear radiofrequency catheter ablation lesions suggest the relative safety and high efficacy of these procedures. However animal models may not be relevant to human pathology because of the small size of atria, different pathophysiologic substrates, and the lack of data pertaining to spontaneous initiation of atrial fibrillation. Preliminary human studies show a higher success rate when linear ablations are performed in the left atrium than in the right atrium and that arrhythmogenic foci play a significant role in atrial fibrillation. However the procedures are prolonged, and it is difficult with current technology to achieve a linear conduction block consistently. The challenge remains to optimize this as yet investigational technique and transform it into a routine procedure.