The text is intended for use by police officers, parents, religious and other community groups, and community college students and as a resource for gang studies and university courses. The introduction explains that gangs as currently identified and classified did not exist until the early 1800’s, when the influx of European immigrants resulted in the formation of groups of young, poor, undereducated, and generally unskilled people of similar ethnic origins; the reasons were social and economic. However, historically, every previous society has displayed evidence of the presence of gangs. Street gangs have existed in the United States since the beginning of the 20th century. The two categories of gangs are social gangs and criminal gangs. Reasons for joining street gangs include family values and poverty, protection, intimidation, financial gain, lack of punishment for gang activity. Gangs are associated with an inherent violence that poses a serious threat to society. Many promising approaches currently exist to address gangs. A small investment today, based on a plan and community support, will save vast amounts of future resources and encourage a generation of youths to become active, constructive participants in society. Figures and lists of names and slang terms