Background: Gender-based stigma contributes to increased HIV prevalence, but little is known about psychosocial mechanisms linking stigma and HIV risk among young transgender women (YTW).Setting: This study uses data from Project LifeSkills, a randomized controlled efficacy trial of an empowerment-based HIV prevention intervention for YTW (N = 233). YTW were recruited in Boston, MA, and Chicago, IL, between 2012 and 2015 and completed study assessment visits at baseline and months 4 and 12.