The document discusses gender dysphoria and related concepts. It provides information on the prevalence of gender dysphoria, biological and psychosocial theories of causation, and diagnostic criteria according to the DSM-5 which includes a strong and persistent cross-gender identification and discomfort with one's sexual characteristics. The document also outlines various treatment approaches and covers related conditions such as transsexualism, dual-role transvestism, and gender identity disorder of childhood.