Gender dysphoria is a term used by psychologists and physicians. It describes people who strongly feel they are not the gender they were born with. It used to be called "gender identity disorder." But it is not a mental illness. It is a condition accompanied by stress, anxiety, and depression. To be diagnosed with gender dysphoria now, patients must exhibit strong cross-gender feelings that persist over time. It is not just a desire to change sex for some advantage they might think exists.