With the rise of the #MeToo movement, there has been a groundswell of attention to sex-based harassment. Organizations have pressured high-level personnel accused of harassment to resign, or fired them outright, and they have created or revised their anti-harassment policies, complaint procedures, and training programs. This article reviews social science and legal scholarship on sex-based harassment, focusing on definitions and understandings of sexual (and sex-based) harassment, statistics on its prevalence, the consequences of harassment both for those who are subjected to it and for organizations, and explanations for why sex-based harassment persists. We then discuss the various steps that organizations have taken to reduce sex-based harassment and the social science literature on the effectiveness of those steps. We conclude that many organizational policies prevent liability more than they prevent harassment, in part because courts often fail to distinguish between meaningful compliance and the merely symbolic policies and procedures that do little to protect employees from harassment.