This small monograph, a doctoral thesis, is a presentation of clinical, physiological, and radiological observations of a group of 67 individuals with aortic stenosis, either pure or with some aortic regurgitation. The cases have been well studied and the reader has the opportunity from the extensive and detailed tables to glean a great deal regarding the attributes of this particular group. The author was not impressed by paradoxical splitting of the second heart sound, the murmur was far more often transmitted up the left side of the neck than up the right side, and when the murmur was maximal in the first half of systole, the gradient across the valve tended to be low. He stresses that the essential angiographic finding was one of decreased mobility of the cusps. The observation of others that the resting cardiac output is usually normal until the patient has significant symptoms was confirmed.