Introduction: The objective of this work is to compare the cases of transsexuality studied in the Forensic Medical Clinic of Madrid with those published in other series. Material and methods: A retrospective, descriptive, cross-sectional, and observational study was carried out by collecting a series of data from the reports issued by forensic doctors attached to the Forensic Medical Clinic of Madrid, from 11 January 1995 to 4 May 2007. Results: A total of 52 reports were obtained in relation to transsexuality, of which 29 were from male to female (55.76%), and 23 from female to male (44.23%). It was noted that the majority lacked psycho-pathological disorders (72.4/65.2% male/female, respectively), the early onset of transsexual sentiment (86.2/100%), the age of re-assignment surgery (male between 18 and 41 years of age; female, between 22 and 43 years old), and its proximity to the application for change of registration. Conclusions: The study emphasises the high incidence of absence of psycho-pathological prob- lems (observed in approximately one-third of the cases), the precociousness in the appearance of the transsexual feeling and the proximity between the surgery and the application for reg- istration, conditioned by the current legal requirements. The results obtained in the present study are compared with other series, taking into account the difference in the procedures used.