"Conversion therapy" or "reparative therapy" is a pseudoscientific practice of attempting to "convert" or "repair" an individual's sexual orientation or gender identity. The concept is founded on the assumption that sexual orientation can be changed and that anything other than heterosexual and cisgender is "abnormal."

Conversion therapy is often conducted by religious groups with the use of prayer and other religious efforts and teachings. While some individuals may undergo this therapy voluntarily, many children are forced into it by their parents. Many medical and psychologist groups have officially condemned this type of harmful "therapy." Some studies have shown that the process can sometimes lead to depression, self-harm, and even suicide.

The practice of attempting to "cure" homosexuality dates back at least to 1888 when a German psychiatrist Richard von Krafft-Ebing used hypnotic suggestion therapy to turn a gay man straight. In the past few decades, countries, provinces, and states have begun outlawing conversion therapy.