The obligation to prevent human rights violations has received little attention in the international human rights community, including in academic commentary. This article considers the sources of the obligation to prevent violations in international human rights law and explores some of the content of the obligation. This leads to a recognition that this obligation may challenge the way we often approach human rights violations and what States need to do to comply. While much of the attention to human rights violations tend to be retrospective--after they have occurred, the obligation to prevent violations requires that action be taken before individuals and groups of individuals become victims.