Sex and gender are often conflated, but there are important distinctions between the two. This is true also with terms related to gender identity, including masculinities and femininities or the performance of gender. In addition, the terms gang and gang member are contested, so it is important to establish a basis for understanding these terms in order to discuss the relationships between gender and gang involvement. Historically, gang-involved young women and men were described in terms of gender extremes, with scholarship and journalistic accounts focusing on the perceived aggressive masculinity of lower class males—and the deviant sexuality of females, who were rarely seen as legitimate full-fledged members of those groups. By the 1980s and 1990s, young women were recognized in scholarship as “real” gang members, and qualitative researchers sought to provide voice to them and examine issues of gender and gender dynamics in gangs, while quantitative researchers sought to explore similarities and differences between girls and boys in gangs, often through large scale studies using self-report surveys of adolescents. Feminist criminology and burgeoning queer criminology have pushed and blurred the boundaries of gender and gang involvement, asserting the importance of taking into account multiple, intersecting identities that differentially structure the experiences of young people, and of the troubling heteronormative, heterosexist, and cisgendered assumptions that have permeated criminology. Moving away from these assumptions means accounting, for example, not only for gender but also for the multiplicative effects of race, ethnicity, class, sexuality, ability, etc.; it means considering what the presence of young women in stereotypically hypermasculine environments signifies for gender performance, moving away from assumptions of opposite sex attraction that cast females in supportive and dependent roles with males, and accounting for the experiences of gang members who identify outside gender and sexual orientation binaries. These issues provide fruitful avenues for sensitive and productive future scholarship on gender and gang involvement.