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 information on the molecular biology of the androgen receptor and its disorders. The key role of testosterone in spermatogenesis is now better de fined. We have a more complete understanding of the psychotro pic effects of testosterone and know so much about the different target organs and functions that individual chapters deal with testosterone and the prostate, lipids and the cardiovascular sys tem, hair, bones and muscles. The general chapter on pharmacol ogy and clinical uses of testosterone, in particular in male hypo gonadism, is extended by pharmacokinetic studies on testoster one preparations and individual substitution modalities using testosterone esters as well as implants and advanced trans dermal applications. The physiologic basis and possible clinical applica tions of testosterone in non-gonadal diseases, in male senes cence, in hormonal male contraception and in transsexuals are discussed. The last chapter describes the role of "investigative" steroid biochemistry applied to tracking anabolic steroid abuse.

1. Testosterone: An overview of biosynthesis, transport, metabolism and nongenomic actions

2. The androgen receptor: Physiology and pathophysiology
3. Behavioural correlates of testosterone
4. The role of testosterone in spermatogenesis
5. Androgens and hair
6. Androgens and bone metabolism
7. Androgens and muscles
8. Androgens, cardiovascular risk factors and atherosclerosis
9. Androgens and the prostate
10. Pharmacology and clinical uses of testosterone
11. Comparative pharmacokinetics of testosterone esters
12. Clinical pharmacology of testosterone pellet implants
13. Long-term experience with testosterone replacement through scrotal skin
14. A permeation-enhanced non-scrotal testosterone transdermal system for the treatment of male hypogonadism
15. Percutaneous dihydrotestosterone treatment
16. Androgens in male senescence
17. Androgen therapy in non-gonadal disease
18. Testosterone in male contraception
19. Androgen treatment of female-to-male transsexuals
20. Abuse of androgens and detection of illegal use.