This is a valuable addition to the physiological and clinical literature on cerebral circulation. After a brief description of the arterial and venous cerebral system, in which the results of cerebral angiography are emphasized, the physiology and pharmacology of cerebral circulation are discussed. These investigations are largely based on the measurement of the diameter of the pial vessels and temperature changes in various parts of the brain. Since definite species differences exist in the reactivity of the cerebral vessels to physiological factors and to drugs, the development by Kety and Schmidt of a quantitative method for the determination of cerebral circulation which is applicable to man was of greatest importance. The results obtained with this method in several clinical conditions are described. This little book is highly recommended to physiologists and clinicians. The bibliography is rather incomplete.