Social contexts of the study included eight county jails in both rural and urban areas of Iowa and Illinois (891 inmates), matched pair design samples from a Chicago public high school (87 gang and 87 nongang students) and an inner-city program (36 gang and nongang members), and 58 gang members in a private suburban probation program. The jail study showed that gang problems in the midwest had a large ripple effect; that gang membership significantly differentiated many variables about firearms, violence, behavior, and beliefs; that gang membership could be predicted with 81 percent accuracy using discriminant analysis; and that gang density was higher than levels previously estimated in a national assessment of gangs in corrections. Gang member profiles in the high school and in the inner-city program were similar to those found in other social contexts. The probation study found that 69 gang members in the suburban-based probation program had the same gang profile as in other settings, although suburban gang members joined the gang primarily for social rather than economic reasons. In general, gang members in all settings studied exhibited high-risk profiles with respect to guns and violence. A gang risk continuum was observed that showed a consistent violence escalation effect from the lowest risk level (nongang member with no gang friends) to the highest risk level (active gang member). Implications of the findings for understanding the relationship between gangs and guns and their relevance to the correctional environment are discussed. 21 references, 25 tables, and 6 figures