For the past 25 years, the author has studied the problem of violence in the lives of children, youth, and families in homes, schools, communities, and war zones around the world. Recently, he interviewed boys incarcerated for committing crimes of lethal violence. His current work focuses on boys who commit more than 90 percent of all lethal assaults and who are the predominant perpetrators of nonlethal assaults as well. He has drawn five basic conclusions from his work. First, easy access to lethal weapons can lead to violence; second, difficult relationships, a difficult temperament, and negative experiences can foster violent behavior; third, maltreatment at an early age can spawn violent behavior; fourth, "toxins" in the social environment can contribute to violent behavior; and fifth, a spiritual void is fertile ground for the development of violent behavior. Over the past 25 years, the percentage of children and youth who have mental health and developmental adjustment problems severe and chronic enough to warrant professional intervention has doubled, according to the research of psychologist Tom Achenbach (Achenbach and McConaughy, 1997). The spreading problem of youth violence is related to this larger development. Dealing with youth violence will require both a broadly based prevention perspective on community life and attention to dealing humanely and effectively with troubled, aggressive children early in their lives. 8 references