The National Profile of Children Exposed to Family Violence: Police Response, Family Response and Individual Impact study provides the first nationally representative data on youth contact with law enforcement and victim services - including best practices and help-seeking obstacles - for cases of family violence involving exposure to children. These data come from a nationally representative sample of 517 family violence incidents drawn from the 4,503 respondents to the Second National Survey of Children's Exposure to Violence (NatSCEV II). The NatSCEV study, conducted in 2011, involved telephone interviews with parents of children age 0-9 and with youths age 10-17. Between 13%-58% of law enforcement contacts, and between 34%-97% of advocate contacts, following domestic violence incidents involving a child witness included actions from one or more of 10 best practices. Most law enforcement best practices were associated with increased likelihood of arrest. Almost half of children witnessed an arrest when one occurred, though only 1 in 4 youth were spoken to by police responding to the scene. Youth exposed to domestic violence, as a group, have higher rates of other victimizations and adversities. Although this group reports elevated trauma symptoms, the characteristics of a specific domestic violence incident and the response to that incident by police were generally unrelated to youth's current trauma symptoms after controlling for history of victimization and other adversities. However, child current trauma symptoms were lowest when perpetrators left the house after the incident, followed by when no one moved out, and were highest when the victim moved out. Child witnesses to family violence are a highly victimized group, and it is recommended that they systematically receive assessment and services when any member of their family enters the system due to family violence.