The right of sexual autonomy now occupies a central place in the scheme of constitutional liberties. Consensual sexual relations, including fornication, adultery, and sodomy, are understood to lie beyond the reach of law’s regulatory power. Yet as described in this Article, some sexual encounters by their very nature are likely to engage unconscious psychological processes that involve troubling levels of vulnerability and coercion. Drawing on psychoanalysis, this Article proceeds by examining three relationships that raise heightened concerns about unconscious impairments in sexual choice. Part I investigates the way in which adult incest may trigger unconscious feelings of submission on the part of the adult child, thus potentially (although not necessarily) justifying legal intervention. Part II examines therapist–patient sexual relations, where transference feelings can raise similar concerns about unconscious impairments in choice and the possibility (although, again, not the inevitability) of legal intervention. Part III addresses the ideal of sexual autonomy as it applies to sadomasochistic relationships, and concludes that these relationships may surprisingly provide a template for the role of conscious reasoned thinking in facilitating sexual desire. Each of these three relationships shows us a different perspective on the right of sexual autonomy and the uneasy balance between choice and desire that underlies every sexual encounter. Exploring the unconscious dynamics in the relationships studied here—adult incest, therapist–patient sex, and sadomasochistic sex—leads us to a deeper understanding of the right of sexual autonomy, and its limits.