The decade that has passed since publication of the second edition of this textbook has not only witnessed a tremendous increase in knowledge within the ? eld of and- logy, but also seen the ? eld itself achieve a newfound status within the medical p- fession. Knowledge and status have been of mutual bene? t to the ? eld and the growing critical mass of diagnostic and therapeutic possibilities have caused andrology to be recognized as a medical subspecialty in some countries such as Germany, Poland, and Estonia. The European Academy of Andrology (EAA) served as a pacemaker for this...

The first edition of "Testosterone: Action, Deficiency, Substitu tion" was published in 1990. Since then our understanding of the hormone that turns males into men has tremendously increased. Therefore, the editors felt that a second extended edition of the book is warranted in order to summarize established and recent findings in the field and to present the reader with an up-to-date is reflected by the textbook. The increased mass of knowledge growth of the volume from 14 to 20 chapters. In the updated edition the biochemistry and metabolism of androgens have been complemented by extensive...