Some researchers and theorists are convinced that graphic scenes of violence on television and in movies are inextricably linked to human aggression. Others insist that a link has not been conclusively established. This paper summarizes scientific studies that have informed these two perspectives. Although many instances of children and adults imitating video violence have been documented, no court has imposed liability for harm allegedly resulting from a video program, an indication that considerable doubt still exists about the role of video violence in stimulating human aggression. The author suggests that a small group of vulnerable viewers are probably more impressionable and therefore more likely to suffer deleterious effects from violent programming. He proposes that research on video violence be narrowed to identifying and describing the vulnerable viewer.