The system acknowledges that youth join gangs for reasons related to peer pressure, status, respect, power, intimidation, low self-esteem, dysfunctional families, economics, lack of realistic alternatives, lack of cultural pride, and lack of gang awareness education. Gang members commit such crimes as robbery, drive-by shootings, rape, extortion, murder, assault, battery, arson, intimidation, and kidnaping because they feel hopeless and experience self-contempt, frustration, and anger. Crime and antisocial behavior represent the common bonds of all gangs. Territory is also important, and graffiti is frequently used to identify the geographic area or turf that a gang considers its own. Gang members dress according to gang characteristics, commonly have tattoos, and use hand signs and other forms of language as a way of bonding. Levels of gang involvement in Los Angeles are examined, and stages of gang development are reviewed. A gang control assessment guide is provided that is designed to increase community awareness of the gang phenomenon. Ways of mobilizing community resources to prevent gang involvement are described, including the Target Area Coordinating Committee concept and associated action campaigns. Worksheets to assist in the conduct of action campaigns are included. Figures