Introduction Youth Violence Developmental Pathways and Prevention Challenges Linda L. Dahlberg, PhD, Lloyd B. Potter, PhD, MPH Abstract Youth violence is an important public health problem. During the latter half of the 1980s and early 1990s, the United States witnessed unprecedented levels of violence among the nation’s youths. Homicide remains one of the leading causes of death for young people aged 10 to 24 years. This paper reviews the major trends in homicide victimization and perpetration among youths during the past decade, the developmental pathways of delinquent and violent behavior and the context in which these behaviors occur, and some of the challenges associated with disrupting these pathways and preventing violence. Previous research reveals that multiple pathways lead toward violence and delinquency. Predicting which pathway a youth will follow, or if one will be followed at all, depends to some extent on a host of other biological, psychosocial, and environmental factors present as young people transition from early childhood to adolescence to early adulthood. Preventing violence requires a comprehensive approach that takes into account develop- mental needs, tasks, and supports. Medical Subject Headings (MeSH): adolescence, aggression, behavior, child development, crime, homicide, primary prevention, risk factors, violence (Am J Prev Med 2001;20(1S):3–14) Introduction S everal school shootings during the past few years, most notably the mass murder–suicide at Colum- bine High School in Littleton, Colorado, have cast the spotlight on youth violence. School-associated vio- lent deaths, however, are relatively rare events 1 and more symptomatic of the much larger problem of youth violence in the United States. Homicide is the third leading cause of death for persons aged 5 to 14 years, the second leading cause of death for persons aged 15 to 24 years, 2 and has been the leading cause of death for African Americans in these age groups for more than a decade. Rates of homicide among chil- dren, adolescents, and young adults in the United States exceed those of their counterparts in other developed nations by several-fold. 3,4 Unlike the thousands of homicides that occur each year among young people, violent deaths that occur in schools make parents, school officials, and policymak- ers pause and ask a number of important questions. Researchers and practitioners who work in the area of violence prevention know that the answers to the problem of youth violence are not simple. Violence is a complex phenomenon. The first step toward prevent- ing violence, according to the public health approach, is to identify and understand the factors that place young people at risk for violent victimization and perpetration. This involves understanding the many precursors of violence, including the role of early childhood environments on later violent behavior, as well as understanding how other biological, psychoso- cial, and environmental factors relate to youth violence. The purpose of this paper is threefold: (1) to provide an overview of homicide victimization and perpetration among youths during the past decade, (2) to describe the developmental pathways of delinquent and violent behavior and the context in which these behaviors occur, and (3) to describe some of the challenges associated with disrupting these pathways and prevent- ing violence. Definition of Violence Public health researchers define violence as the “threat- ened or actual use of physical force against a person or a group that either results or is likely to result in injury or death.” 5 In recent years, researchers have expanded the definition to include other possible outcomes, such as psychological harm, maldevelopment, and depriva- tion. Fatal (e.g., homicide) and nonfatal (e.g., assaul- tive behavior) outcomes are of particular interest as are the specific mechanisms and intent of injury. The inclusion of other outcomes reflects a growing interest among public health researchers to capture violence that does not necessarily result in injury or death, but From the Division of Violence Prevention, National Center for Injury Prevention and Control, Centers for Disease Control and Prevention, Atlanta, Georgia Address correspondence and reprint requests to: Linda L. Dahl- berg, PhD, NCIPC, Division of Violence Prevention, Mailstop K60, Centers for Disease Control and Prevention, 4770 Buford Highway NE, Atlanta, GA 30341. E-mail: ldahlberg@cdc.gov. 3 Am J Prev Med 2001;20(1S) 0749-3797/01/$–see front matter Published by Elsevier Science Inc. PII S0479-3797(00)00268-3