In 1951 WOLFGANG MAUERMAYER was one of the first young German urologists to visit the United States, after the war. He brought a very personal enthusiasm, and joy in learning, to many well known clinics in both the eastern and western United States. It was then that I first had the pleasure of meeting him; and, since then, we have enjoyed each other's company on a number of occasions. From California (and during a half year sabbatical in Berlin) I have followed the course of his exceptional career. He has transformed his Munich Clinic into one of the leading European centers for transurethral surgery. His first book on transurethral operations, published in 1962, appeared only in German. Consequently, it is little known in the United States and England. The present book, now in its first English edition, is the result of more than 30 years experience in transurethral surgery. During this time more than 10,000 patients were treated in Mauermayer's clinic by various endoscopic oper ations. His unusual reservoir of experience forms the basis for this book. It seems of particular importance that surgical techniques are described in a number of steps, since this enables even a novice to understand the various procedures.