Transsexuality is a disorder of gender identity in which physical appearance does not align with emotional experience. The Transsexual Law of 1980 established a legal framework that addresses the specific situation of transgender individuals. However, there is still a significant need for improvement in the acceptance afforded to transgender people. The first edition of this therapy guide quickly sold out. The entire content has been thoroughly revised and updated to the latest standards. Historical and epidemiological aspects are presented, along with an overview of the development of normal and disturbed gender identity, as well as the nosology, symptoms, and course of transsexual gender identity disorders. Important legal considerations are addressed in as much detail as the topic itself.