A system and method of identifying a driver of a source associated with a heart rhythm disorder are disclosed. Data is accessed from a plurality of sensors representing biological activity in the heart. A local first region of the heart that has repeating activation and that controls a second distant region of the heart for at least a predetermined number of beats is identified. The first local region is assigned as a driver of a source of the heart rhythm disorder, the source including the first local region and the second distant region.