For decades clinical electrophysiology has been considered a discipline for adepts, able to interpret not so obvious intracardiac signals. With the advent of new technologies, offering a three-dimensional reconstruction of cardiac anatomy and generating colour-coded maps, the approach to the complex world of electrophysiology is changing: A three-dimensional colour-coded electroanatomic map of a left atrium could be a precise and self-explanatory representation based on intracavitary signals, on which correct diagnosis is made and successful ablation is performed. As expected, this makes the difference especially in cases exhibiting complex arrhythmias (atypical atrial flutters, postsurgical arrhythmias), in which the task could be really tough. The book is based on a multicentre experience and describes the most difficult cases of each centre, as far as arrhythmia is concerned. For each case, the crucial role of electroanatomic mapping in providing unique information and new insights in a field still in evolution is very evident. The book will prove to be very a useful tool for all the operators working in this field.