The shootings at Virginia Tech University in April 2007 have again brought home the tragic consequences of violence. As yet another instance of senseless aggression unfolded, the nation watched as details emerged about the perpetrator and the deaths of 32 students and professors. The shooter, Seung-Hui Cho, lived a troubled life characterized by social isolation, alienation, and depression. Furthermore, professors at Virginia Tech had recognized erratic behavior in Mr. Cho and had referred him for counseling and mental health treatment on several different occasions. On the other hand, Mr. Cho's victims were, by all accounts, normal students going about their daily routines. Sadly, we could easily substitute the name of any U.S. university for Virginia Tech. Images of what happened on April 16 in Blacksburg have filled the thoughts and minds of university students, faculty, and staff across the nation. Reports of frantic parents trying to reach their loved ones and of cell phones ringing in the pockets of dead students affected the psyche of an entire country. The Virginia Tech shootings were preceded by deadly violence on at least 12 other college campuses dating to the well-known Kent State shootings of 1970. It is disturbing that seven of these 12 incidents have occurred since 1991; four have happened since 2000 (Smith, 2007). The shootings at Virginia Tech remind us that violent behavior often occurs in unexpected places under hard-to-predict circumstances. It is interesting that recent shootings on U.S. campuses have occurred when rates for most types of aggression and violence have achieved their lowest levels in years. TRENDS IN AGGRESSION AND VIOLENCE Trends in aggression and violence generally mirror a host of individual, social, and economic patterns. For example, the well-documented increase in youth violence between the late 1980s and mid-1990s was linked to increases in gang involvement and crack cocaine use. Conversely, reductions in youth violence in the past decade have been associated with the implementation of innovative law enforcement strategies, improvements in economic opportunities, and efficacious prevention approaches in communities and schools (Blumstein & Wallman, 2006). Disentangling and interpreting trends in violent conduct, however, is a daunting task for policy officials and practitioners. Offender and victimization data compiled by the U.S. Department of Justice reveal a decrease in violence between the mid-1990s and 2004. For example, the rate of violent crime for the offenses of murder, forcible rape, robbery, and aggravated assault decreased 26% between 1996 and 2004 (Crime in the United States 2004, 2005). Similarly, data from the National Crime Victimization Survey, an annual household survey of crime victimization in the United States, indicate that the victimization rate for violent crime fell to an all-time low of 21 incidents per 1,000 residents in 2005 (Bureau of Justice Statistics, 2007). Finally, a decline in juvenile violence has also been reported widely in recent years; for example, the arrest rate for violent crimes by youths under the age of 18 decreased by 49% between 1994 and 2004 (Snyder, 2006). However, an increase in violent crime rates among adults in the past few years may signal an end to the downward turn in violent crime in the United States. Notably, overall violent crime increased by a little more than 2% between 2004 and 2005 (Crime in the United States 2005, 2006), and data released in 2007 by the Federal Bureau of Investigation indicate that violent crime increased 1% between 2005 and 2006 (http://www.fbi.gov/ucr/ucr.htm). Data published later this year will show whether similar increases are occurring among persons under age 18. In sum, trends of violent conduct in the United States reveal both optimism and concern. On the one hand, a decade-long decline in violence has led to a greater sense of security among many citizens and to more opportunities for people at greatest risk of criminal involvement. …