In this presentation, we will review the diagnostic criteria for gender dysphoria (DSM-5-TR) and gender incongruence (ICD-11) in children and adolescents/adults, including a review of differential diagnoses and prognostic factors in DSM-5-TR. We will then consider language, culturally competent practice, and gender-affirming care for individuals with gender dysphoria and people who identify as transgender and gender-diverse (TGD) clients. The presenter will emphasize the need to differentiate between clients with gender dysphoria and individuals who identify as TGD and review the prevalence of gender dysphoria and TGD identity in the U.S. population. To effectively consider aspects of what is now named gender dysphoria across the life course, we will examine the history of the nomenclature and diagnostic issues since the diagnoses of gender identity of childhood and transsexualism were first introduced into DSM-III in 1980. Importantly, we will look at the association between gender dysphoria and self-harm, suicidality, and mental illness for adolescents and adults separately. Finally, we will review the 2022 Standards of Care of the World Professional Association for Transgender Health for children, adolescents, and adults by age category.