This is the third edition of the book which was first published in 1985. There has been tremendous progress in the last 10 years since the second edition, especially in the electrocardiography of acute myocardial infarction. With the advent of the thrombolytic era, many new insights into the electrocardiography of acute myocardial infarction have emerged.In this new edition, the sections on posterior myocardial infarction, supraventricular tachycardia, ventricular tachycardia and anti-arrhythmic drug therapy have all been updated or revised. One of the strengths of the previous two editions has been the quality of the illustrations. In keeping with this tradition, the illustrations in this third edition have been improved further, with 57 (40%) of the 142 illustrations being new.Books, monographs and scientific papers on electrocardiography abound and it would appear that there is little justification for yet another book on this subject. However, despite the voluminous publications, it is difficult to find books on electrocardiography which are simple, concise, accurate and relevant to patient care.This book is the culmination of about 30 years of experience in the teaching of electrocardiography to coronary-care-unit nurses, medical undergraduates, interns, residents and cardiology registrars. As the title of the book implies, the approach to the subject has been entirely from the viewpoint of a clinician. Hence, theoretical considerations have been kept to a mimimum and clinical-electrocardiographic correlations have been emphasized throughout the text.