Nicolosi described his ideas in Reparative Therapy of Male Homosexuality: A New Clinical Approach (1991) and three other books. Medical institutions warn that conversion therapy is ineffective and may be harmful, and that there is no evidence that sexual orientation can be changed by such treatments. Nicolosi was a founder and president of the National Association for Research and Therapy of Homosexuality (NARTH). Joseph Nicolosi (Janu– March 8, 2017) was an American clinical psychologist who advocated and practised 'reparative therapy', a form of the pseudoscientific treatment of conversion therapy that he claimed could help people overcome or mitigate their homosexual desires and replace them with heterosexual ones.
