The increase in the aggregate homicide rate was due to escalating rates among juveniles and youths, predominantly, although not exclusively, by and against Black males, particularly in larger cities and exclusively involving handguns. By 1999, the rate of homicides perpetrated by youths finally returned to the stable rate that existed from 1970 through 1985. Although the causes of the increase in violence are fairly clear -- homicides by youths with handguns, mostly as a result of diffusion out of drug markets -- the factors that contributed to the decline are more complex. They include efforts by local police, communities, and Federal agencies to separate youths from their guns. These efforts have been aided significantly by the waning of crack markets, especially the diminished participation of youth in these markets. As an alternative, the robust economy has provided legitimate job opportunities for youth, which has provided incentives and alternatives to illegal activities. For older offenders, the increase in incarceration has been an important component in reducing violent crimes, although other factors have also been involved in the decline of adult violence. These include the widespread availability of domestic violence services, which apparently have contributed significantly to the reduction in male victimization in homicides. The Uniform Crime Reports for the first half of 2000 were released by the FBI in mid-December 2000; they indicated that both crime and homicide declined by a mere 0.3 percent. This could be an indication that the crime decrease has finally flattened out. Regardless, policymakers should take advantage of the current relatively low crime rate to better understand the factors in crime trends and pursue criminal justice and community-based policies to forestall the next crime increase as long as possible. Of particular concern should be the resurgence of active drug markets and associated violence and a downturn in the economy, which has been associated with an increase in violence. 9 exhibits, a question-and-answer session, and 16 notes