There is a long history for Purkinje cells. In 1845, Purkinje first described Purkinje fibers strands on the endocardial surface of sheep hearts. In 1906, Tawara described these strands as a dense layer of connective tissue surrounding short cells (Purkinje cells) which have variable shapes and could from bundles that branched within the septum forming a network along the endocardial surface. Structural studies continued with various reports about the presence and absence of t-tubules, thus distinguishing Pcells from their ventricular cell neighbors. Recent data suggest that t-tubules occasionally are present in Purkinje fibers but their frequency depends on the size of the heart. During this presentation we will first review what is known about the differences in intrinsic ion channel function between Purkinje cells and ventricular cells that underlie their markedly different action potential phenotypes. Second we will discuss what is known about the differences in EC coupling that separate the Purkinje cell from the ventricular cell and their potential for reverse EC coupling. Finally we will discuss what is known about the remodeled Purkinje cell in terms of enhanced pacemaker function.