This study examined sexual orientation change efforts (SOCE) by 1,612 individuals who are current or former members of the Church of Jesus Christ of Latter-day Saints (LDS). Data were obtained through a comprehensive online survey from both quantitative items and open-ended written responses. A minimum of 73% of men and 43% of women in this sample attempted sexual orientation change, usually through multiple methods and across many years (on average). Developmental factors associated with attempts at sexual orientation change included higher levels of early religious orthodoxy (for all) and less supportive families and communities (for men only). Among women, those who identified as lesbian and who reported higher Kinsey attraction scores were more likely to have sought change. Of the 9 different methods surveyed, private and religious change methods (compared with therapist-led or group-based efforts) were the most common, started earlier, exercised for longer periods, and reported to be the most damaging and least effective. When sexual orientation change was identified as a goal, reported effectiveness was lower for almost all of the methods. While some beneficial SOCE outcomes (such as acceptance of same-sex attractions and reduction in depression and anxiety) were reported, the overall results support the conclusion that sexual orientation is highly resistant to explicit attempts at change and that SOCE are overwhelmingly reported to be either ineffective or damaging by participants.