Risk factors are variables increase the likelihood of the outcome in question—in this case, gang membership. Gang research scholars have discovered a multitude of risk factors that are statistically linked to gang joining. These individual risk factors span the many dimensions in a youth’s life and are typically grouped into five categories (called “domains”): individual, family, school, peer, and neighborhood/community. Importantly, however, these extensive research studies have demonstrated that there is no one risk factor (or even domain) responsible for gang joining; rather, it is the accumulation of multiple risk factors across multiple domains that greatly increases gang joining. Thus, put another way, gang joining is not reducible to a single risk factor (e.g., single-parent household), since some youth with the risk factor may not join a gang, and some youth without the risk factor may join. It is far more profitable, then, to assess (and ultimately address) the collection of risk factors across the five social domains to prevent gang joining.