The CGI asserts that as an unincorporated association, a gang has engaged in criminal and other activities that constitute a public nuisance. Specific gang members are liable for civil actions as a consequence of their membership in the association. CGI's are spatially based, neighborhood-level interventions intended to disrupt a gang's routine activities. The injunction targets specific individuals, and often other unnamed gang members, who adversely affect the daily lives of neighborhood residents through intimidation and public nuisances, while restricting residents' activities within the boundaries of a defined geographic space. Southern California has gangs of all types, with the region encompassing both chronic and emergent gang cities, an array of ethnic and national origins among its gang participants, drug gangs, skinheads, and prison gangs. Southern California has been a laboratory for injunction implementation. This chapter uses several case studies to illustrate some important dimensions of CGI's, such as their flexibility and emphasis on partnerships. It then reviews the available evidence pertinent to the impact of CGI's and the legal issues that have been raised. The chapter concludes with a discussion of how this new intervention strategy might be placed in several categories of the Spergel and Curry (1993) gang intervention typology. The analysis shows that CGI's do not fit neatly within any one category of the Spergel/Curry typology. The flexible nature of the CGI as a gang intervention strategy defies simple categorization. The authors argue that the paucity of independent, scholarly evaluation of the effect of CGI's should raise some concerns about their accelerated use. Each of the 32 injunctions issued in southern California in the 1990's offers an opportunity for a field test of some of the issues raised in this chapter. 2 figures, 9 notes, and 52 references