Homicide-followed-by-suicide (referred to as "homicide-suicide") incidents are rare events but can have a profound impact on families and communities. A better understanding of perpetrator characteristics and how they compare with those of other homicide suspects and suicide decedents might provide insight into the nature of these violent acts. This report is based on 2003-2005 data from 17 US states participating in the National Violent Death Reporting System, a unique, incident-based, active surveillance system that integrates data on violent deaths from multiple sources. Of the 408 homicide-suicide incidents identified, most incidents were committed with a firearm (88.2%) and perpetrated by males (91.4%), those over 19 years of age (97.6%), and those of white race (77.0%); however, just over half of filicide (killing of children)-suicides (51.5%) were perpetrated by females. Over 55% of male homicide-suicide perpetrators versus 26.4% of other male suicide decedents had prior intimate partner conflicts (P < 0.001). In fact, having a history of intimate partner conflicts was even common among homicide-suicide perpetrators who did not victimize their intimate partners. Recognition of the link between intimate partner conflicts and homicide-suicide incidents and strategies involving collaboration among the court/legal and mental health systems might prevent these incidents.