Relational trauma can be understood as a psychological injury that occurs in the context of abusive interpersonal relationships and appears to be correlated with a wide array of mental illnesses. However, one potential harm of trauma that has not received much attention from philosophers is the threat it poses to authenticity. To understand why relational trauma potentially creates impediments to authentic agency, we need to consider two other phenomena that are commonly associated with it: (i) dissociation, and (ii) diminished habitual trust. Whereas trauma-related dissociation commonly involves bodily alienation and detachment from the self, diminished habitual trust often leads to alienation from others. I maintain that dissociative detachment and diminished habitual trust often are mutually reinforcing and that, together, they can cause agents to become disconnected from themselves, others, and the reality of what has happened to them. What implications does this have for authentic agency among traumatized individuals? After outlining existing conceptions, I emphasize the important sense in which authenticity is relational and scaffolded by social connections. I also discuss several competencies that undergird authenticity and argue that the interplay between dissociative detachment and attenuated habitual trust can make it difficult for traumatized individuals to develop and sustain these competencies. Thus, the trauma they have experienced impedes their ability to conduct their lives in accordance with their genuine cares and desires.