American teenagers have grown up surrounded by gun violence and guns have played a significant role in the development and behavior of many inner-city youth. This article reviewed the lessons of the epidemic of youth gun violence. It begins with a review of what is currently known about adolescents and guns, pulling various research findings together to offer an overall picture of adolescent gun attitudes and behaviors. It then summarized recent trends in youth violence in relation to guns. New findings were presented from in-depth interviews with 377 active gun offenders from 2 socially isolated inner-city neighborhoods. The article continued with descriptive counts on a sample of several previously measured variables relating to gun acquisition and use. An attempt was made to close the knowledge gap by presenting a summary of a detailed analysis of gun and non-gun use in violent acts. In closing, a social autopsy of 10 recent multi-victim school shootings in rural and suburban communities was presented. The crisis of youth gun violence reflected both broader trends in youth violence and significant changes in the material conditions and social controls in the communities where gun violence was most common. Tables and references