This booklet is dedicated to the memory of Alan E. Lindsay, MD (1923-1987) master teacher of electrocardiography, friend, mentor, and colleague. Many of the excellent ECG tracings illustrated in this learning program are from Dr. Lindsay's personal collection of ECG treasures. For many years these ECG's have been used in the training of medical students, nurses, housestaff physicians, cardiology fellows, and practicing physicians in Salt Lake City, Utah as well as at many regional and national medical meetings. .