Youth gangs pose a significant challenge for communities across the United States, in urban, suburban, and rural areas alike. Nationwide, 23% of students report the presence of gangs at their schools (Dinkes, Kemp, & Baum, 2009), and approximately 35% of law enforcement agencies indicate gang problems (such as gang-related crime) in their jurisdictions (Egley & O’Donnell, 2009).(see footnote 1) Self-reported youth surveys show varying estimates of gang membership, from single digits among a national sample of students to about 30% among high-risk youth in large cities (Howell & Egley, 2009).For this Focus, NCCD analyzed data from national, state, and local youth surveys and drew on the results of previous gang research to provide a snapshot of youth gangs. This includes a summary of risk factors for gang membership and selected characteristics of gang-involved youth. California, which has faced significant and disproportionate levels of gang membership for decades, serves as a state case study. The local data highlight the San Francisco Bay Area cities of Oakland and Richmond; both Oakland and Richmond have entrenched gang problems and very high homicide rates.(see footnote 2)