In light of possible emulation of the German Transsexuals' Act (TSG) in discussions taking place on future legislation in other states, on the 10th anniversary of the German TSG, we review the application of this law, as well as epidemiological data arising from its use. From 1981 to 1990, 1422 judicial decisions were rendered in Germany on this basis: 683 of them related to the so-called "small solution" (change of first name), and 733 involved what is termed the "major solution" (legal change of sex status). The frequency of transsexual applications over these 10 years lay between 2.1 and 2.4 per 100,000 German adult population. The average age was 33. Only 3.6% and 10.9% of the small and major applications, respectively, were rejected by courts. The sex ratio was 2.3:1 in favor of male-to-female transsexuals. Data revealed no significant trend over the years among the prevailing practices of adjudication, but evidence does exist that the German courts apply the law differently on a regional basis. Over the 10-year period, only six persons requested to have their names changed back again and only one to be reassigned to the former legal sex classification. Those who change their first names in the sense of a tentative accustomizing process waited an average of 2 years before changing their gender. Between 20 and 30% apparently went no further than the so-called "small solution."