The physician is often plagued by his inability to follow discussions relative to the metabolism of the steroid hormones. Discussants glibly toss about terms such as 3α-ol-17-one, or other terminology dashed with the pregnane nucleus plus side chains of varying lengths, to the utter discomfiture of the uninitiated. The present text contains a clear indoctrination into the mystic realms of steroid structure, physiology, and metabolism, suitable for reading by physicians. The reader is wafted lucidly through steroid nomenclature and structure into the formerly bewildering maze of biosynthesis, microbiological reactions, and enzymatic influences with a sense of comfortable understanding not usual in biochemical textbooks. The book should be of value to the beginner as well as to the research worker in the field of endocrinology.