Atrial fibrillation (AF) is the most common heart rhythm disorder in humans, and a rapidly growing epidemic in Australia. AF occurs because electrical circuits called rotors take over the top chambers of the heart. Until now, ablation procedures to target AF have not been able to specifically target rotors, which has meant operations are often long and arduous. This project uses new mathematical techniques we have developed to localise rotors driving AF, aiming to develop a faster safer and more effective AF ablation.