Transsexualism is a constant feeling of discomfort and inappropriateness in the gender in which a person is born with a tendency to live and be accepted as a person of the opposite sex. Transsexualism has a biological etiology, but the outcome of the disorder is crucial interaction of social and psychological factors. Transsexualism or Gender Identity Disorder is present in all societies and civilizations. It also occurs in children and adult. Much higher incidence of transsexualism is in childhood and male. Treatment of transsexuals includes: psychotherapy, psychopharmacotherapy, hormonal and surgical treatment. During psychotherapy patient determines actual life goals for relations with a partner, family, friends and their job. Conducted training and inclusion in the group to make it through other people's experiences gained more realistic insight into the difficulties brought by the change of gender. If a person meets the criteria for a sex change, and after psychotherapy still has a strong desire to change sex, then it is subjected to a wide range of medical interventions. During this period is introduced in hormonal therapy. The procedure requires that the person before submitting to surgery has to be subjected to so-called "real-life experience". For a period of 1-2 years, a person needs to "live" in the desired gender. If the person is still determined to change gender, then they approach to a surgical sex change. In Croatia, a small number of experts are dealing with transsexuality. Transsexuality is considered just as a psychiatric disorder which contributes to the stigmatization of transsexual people. These people really suffer and often face rejection by family, friends, do not have the financial resources needed to treat, often suffer from depression.