Reports of complete change were uncommon. The majority of participants gave reports of change from a predominantly or exclusively homosexual orientation before therapy to a predominantly or exclusively heterosexual orientation in the past year. On all measures, the year prior to the therapy was compared to the year before the interview. They were interviewed by telephone, using a structured interview that assessed same sex attraction, fantasy, yearning, and overt homosexual behavior. The participants were 200 self-selected individuals (143 males, 57 females) who reported at least some minimal change from homosexual to heterosexual orientation that lasted at least 5 years. Position statements of the major mental health organizations in the United States state that there is no scientific evidence that a homosexual sexual orientation can be changed by psychotherapy, often referred to as 'reparative therapy.' This study tested the hypothesis that some individuals whose sexual orientation is predominantly homosexual can, with some form of reparative therapy, become predominantly heterosexual.