It is interesting that a condition for which the treatment is purely surgical should have fascinated one of the world's greatest clinicians, who contributed much to the history and to the present scientific knowledge of arteriovenous aneurysm. No physician or surgeon can fail to be thrilled by reading the contributions of Sir William Osler on this subject. Immediately one is impressed with the true catholicity of the pure scientific mind which he possessed. He himself stated: "Better than any other disease, aneurysm illustrates how borderless are the boundaries of medicine and surgery." There is a wealth of meaning to be gleaned in this one sentence in this day of necessary specialization which frequently leads, unfortunately, to a contracted point of view of disease as a whole. A study of medical history reveals that the aneurysm has had a particular fascination for many of the greatest masters in medicine. The names