This article provides an overview of current psychological research on mental health and sexual orientation, as well as clinical practice with sexual minorities. The historical context for current research questions and controversies is described, and the findings of recent empirical research on psychological well-being and distress among nonheterosexuals are summarized. The minority stress model is used to frame a discussion of stressors unique to sexual minorities and to consider their possible effects on psychological well-being. The possible ameliorative effects of adopting a sexual orientation identity are examined, followed by a discussion of how these ideas translate into contemporary clinical work with sexual minority clients. The review concludes with a brief discussion of priority areas for empirical research and clinical practice.