It is estimated that between 3.3 million and 10 million children in the U.S. witness physical violence between their parents each year. This type of violence ranges from overhearing some form of violent behavior from their bedrooms, to seeing severe acts of violence such as beatings or assaults with guns and knives. In many cases, these youth observe repeated acts of violence perpetrated by multiple partners throughout their childhood. The little that is known about the effects of interparental violence on adolescents indicates that when compared to youth from non-violent homes, adolescent witnesses of domestic violence have higher rates of aggression, more fatalistic views of the future, and an increased risk for delinquency, school truancy and other risky behaviors. This article discusses common reactions by adolescents who witness interparental violence, and some of the ways in which exposure to this violence may impede adolescent development.