"Sex reassignment therapy" (SRT) is an umbrella term for all medical treatments related to sex reassignment of both transgender and intersex people.

Individuals make different choices regarding sex reassignment therapy, which may include female-to-male or male-to-female hormone replacement therapy (HRT) to modify secondary sex characteristics, sex reassignment surgery (such as orchiectomy) to alter primary sex characteristics, chest surgery such as top surgery or breast augmentation, or, in the case of trans women, a trachea shave, facial feminization surgery or permanent hair removal.

To obtain sex reassignment therapy, transsexual people are generally required to undergo a psychological evaluation and receive a diagnosis of gender identity disorder in accordance with the Standards of Care (SOC) as published by the World Professional Association for Transgender Health. This assessment is usually accompanied by counseling on issues of adjustment to the desired gender role, effects and risks of medical treatments, and sometimes also by psychological therapy. The SOC are intended as guidelines, not inflexible rules, and are intended to ensure that clients are properly informed and in sound psychological health, and to discourage people from transitioning based on unrealistic expectations.

Transsexual people experience a gender identity that is inconsistent with, or not culturally associated with, their assigned sex, and desire to permanently transition to the gender with which they identify, usually seeking medical assistance (including hormone replacement therapy and other sex reassignment therapies) to help them align their body with their identified sex or gender.

"Transsexual" is generally considered a subset of "transgender", but some transsexual people reject the label of "transgender". A medical diagnosis of gender dysphoria can be made if a person expresses a desire to live and be accepted as a member of their identified sex, and if a person experiences impaired functioning or distress as a result of their gender identity.

Treatment for a person diagnosed with GID may include psychotherapy or to support the individual's preferred gender through hormone therapy, gender expression and role, or surgery. This may include psychological counseling, resulting in lifestyle changes, or physical changes, resulting from medical interventions such as hormonal treatment, genital surgery, electrolysis or laser hair removal, chest/breast surgery, or other reconstructive surgeries. The goal of treatment may simply be to reduce problems resulting from the person's transgender status, for example, counseling the patient in order to reduce guilt associated with cross-dressing, or counseling a spouse to help them adjust to the patient's situation.

Hormone treatment or surgery for gender dysphoria is somewhat controversial because of the irreversibility of physical changes. Guidelines have been established to aid clinicians. The World Professional Association for Transgender Health (WPATH) Standards of Care are used by some clinicians as treatment guidelines. Others use guidelines outlined in Gianna Israel and Donald Tarver's "Transgender Care". Guidelines for treatment generally follow a "harm reduction" model.

The question of whether to counsel young children to be happy with their assigned sex, or to encourage them to continue to exhibit behaviors that do not match their assigned sex—or to explore a transsexual transition—is controversial. Some clinicians report that a significant proportion of young children diagnosed with gender dysphoria later do not exhibit any dysphoria.

Professionals who treat gender identity disorder in children have begun to refer and prescribe hormones, known as a puberty blocker, to delay the onset of puberty until a child is believed to be old enough to make an informed decision on whether hormonal gender reassignment leading to surgical gender reassignment will be in that person's best interest.

Transphobia is a range of negative attitudes, feelings or actions toward transgender or transsexual people, or toward transsexuality. Transphobia can be emotional disgust, fear, violence, anger or discomfort felt or expressed towards people who do not conform to society's gender expectations. It is often expressed alongside homophobic views and hence is often considered an aspect of homophobia. Transphobia is a type of prejudice and discrimination similar to racism and sexism, and transgender people of color are often subjected to all three forms of discrimination at once.

Child victims of transphobia experience harassment, school bullying, and violence in school, foster care, and social programs. Adult victims experience public ridicule, harassment including misgendering, taunts, threats of violence, robbery, and false arrest; many feel unsafe in public. A high percentage report being victims of sexual violence. Some are refused healthcare or suffer workplace discrimination, including being fired for being transgender, or feel under siege by conservative political or religious groups who oppose laws to protect them. There is even discrimination from some people within the movement for the rights of gender and sexual minorities.

Besides the increased risk of violence and other threats, the stress created by transphobia can cause negative emotional consequences which may lead to substance abuse, running away from home (in minors), and a higher rate of suicide.

In the Western world, there have been gradual changes towards the establishment of policies of non-discrimination and equal opportunity. The trend is also taking shape in developing nations. In addition, campaigns regarding the LGBT community are being spread around the world to improve acceptance; the "Stop the Stigma" campaign by the UN is one such development.

Therapeutic approaches for GIDC differ from those used on adults and have included behavior therapy, psychodynamic therapy, group therapy, and parent counseling. Proponents of this intervention seek to reduce gender dysphoria, make children more comfortable with their bodies, lessen ostracism, and reduce the child's psychiatric comorbidity. The majority of therapists currently employ these techniques. "Two short term goals have been discussed in the literature: the reduction or elimination of social ostracism and conflict, and the alleviation of underlying or associated psychopathology. Longer term goals have focused on the prevention of transsexualism and/or homosexuality."

Individual therapy with the child seeks to identify and resolve underlying factors, including familial factors; encourage identification by sex assigned at birth; and encourage same-sex friendships. Parent counseling involves setting limits on the child's cross-gender behavior; encouraging gender-neutral or sex-typical activities; examining familial factors; and examining parental factors such as psychopathology. Longtime researchers of gender identity disorder, Kenneth Zucker and Susan Bradley, state that it has been found that boys with gender identity disorder often have mothers who to an extent reinforced behavior more stereotypical of young girls. They also note that children with gender identity disorder tend to come from families where cross-gender role behavior was not explicitly discouraged. However, they also acknowledge that one could view these findings as merely indicative of the fact that parents who were more accepting of their child's cross-gender role behavior are also more likely to bring their children to a clinical psychiatrist as opposed to parents who are less accepting of cross-gender role behavior in their children (Bradley, Zucker, 1997). " Proponents acknowledge limited data on GIDC: "apart from a series of intrasubject behaviour therapy case reports from the 1970s, one will find not a single randomized controlled treatment trial in the literature" (Zucker 2001). Psychiatrist Domenico Di Ceglie opines that for therapeutic intervention, "efficacy is unclear," and psychologist Bernadette Wren says, "There is little evidence, however, that any psychological treatments have much effect in changing gender identity although some treatment centres continue to promote this as an aim (e.g. Zucker, & Bradley, 1995)." Zucker has stated that "the therapist must rely on the 'clinical wisdom' that has accumulated and to utilize largely untested case formulation conceptual models to inform treatment approaches and decisions."

Gender dysphoria in children or gender identity disorder in children (GIDC) is a formal diagnosis used by psychologists and physicians to describe children who experience significant discontent (gender dysphoria) with their biological sex, assigned gender, or both.

GIDC was formalized in the third revision of the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-III) in 1980 and primarily referenced gender non-conforming behaviors. GIDC remained in the DSM from 1980 to 2013, when it was replaced with the diagnosis of "gender dysphoria" in the fifth revision (DSM-5), in an effort to diminish the stigma attached to gender variance while maintaining a diagnostic route to gender affirming medical interventions such as hormone therapy and surgery.

Controversy surrounding the pathologization and treatment of cross-gender identity and behaviors, particularly in children, has been evident in the literature since the 1980s. Proponents of more widespread GIDC diagnoses argue that therapeutic intervention helps children be more comfortable in their bodies and can prevent adult gender identity disorder. Opponents say that the equivalent therapeutic interventions with gays and lesbians (titled conversion or reparative therapy) have been strongly questioned or declared unethical by the American Psychological Association, American Psychiatric Association, American Association of Social Workers and American Academy of Pediatrics. The World Professional Association for Transgender Health (WPATH) states that treatment aimed at trying to change a person's gender identity and expression to become more congruent with sex assigned at birth "is no longer considered ethical." Critics also argue that the GIDC diagnosis and associated therapeutic interventions rely on the assumption that an adult transsexual identity is undesirable, challenging this assumption along with the lack of clinical data to support outcomes and efficacy.

Gender identity disorder in children is more heavily linked with adult homosexuality than adult transsexualism. According to limited studies, the majority of children diagnosed with GID cease to desire to be the other sex by puberty, with most growing up to identify as gay or lesbian with or without therapeutic intervention.

During the year prior to the 2015 U.S. survey, 59 percent of respondents reported avoiding using a public restroom out of fear of violence or harassment. 32 percent limited the amount they ate or drink in order to avoid using a public restroom. Eight percent reported suffering a urinary tract infection, kidney infection, or other kidney problem as a result of avoiding public restrooms.

Thirty-three percent reported having negative experiences with a healthcare professional related to being transgender, such as verbal harassment or denial of treatment. 23 percent reported that they did not seek treatment for a condition out of fear of being mistreated, while 33 percent did not seek treatment because they were unable to afford it.

During the month prior to the survey, 39 percent of American transgender people experienced major psychological distress, compared to 5 percent of the general population of the United States. 40 percent had attempted suicide at some point in their life, compared to 4.6 percent of the American population. Family and community support were correlated with far lower rates of suicide attempts and of major psychological distress.

A study conducted on transgender women of color in San Francisco has shown a higher correlation between transphobia and risk of transgender women engaging in HIV risk behavior. The study shows that the transgender youth face social discrimination, and they may not have a social role model. The young adults in this group have shown a higher risk of engaging in unprotected receptive anal intercourse when the exposure to transphobia is high. Therefore, as per the study shows a correlation between transphobia and high risk of HIV.