Research has consistently demonstrated strong relationships between high levels of adherence to traditional masculinity ideology and poor health and behavior outcomes (e.g., Levant & Richmond, 2007; O'Neil, 2008). Though recent studies have demonstrated support for theories of multiple masculinities or the idea that one's masculinity ideology is developed, maintained, and restructured according to one's social and environmental contexts (e.g., Smiler, 2004), understanding how male gender contributes to social problems within diverse communities, social groups, and contexts is not well established (Mankowski & Maton, 2010). The current study examined how individual and contextual variables predict change in level of adherence to traditional masculinity ideology among a diverse sample of incarcerated adolescent males convicted of felony crimes in the state of Ohio. In particular, while literature has described prison settings as an environment that ignores gender (e.g., Lutze & Murphy, 1999; Messerschmidt, 1993), the current study assessed the effectiveness of a strength-based program at successfully decreasing adherence to traditional masculinity within two of the four participating juvenile justice facilities in ODYS. Using hierarchical linear modeling informed by a qualitative follow-up sequence design, study found younger adolescents and African American youth with low levels of ethnic pride to have higher levels of adherence to traditional masculinity at the beginning of the study compared to older adolescents and White youth or African American youth with high levels of ethnic pride. Interestingly, age did not predict changes in levels of adherence to traditional masculinity ideology over time, however, White youth's level of adherence increased over time and African American youth's level of adherence remained relatively stable. Moreover, youth with good attendance in the program experienced less dramatic increases in adherence to traditional masculinity compared to those with poor attendance. Thematic analysis of qualitative data supports the study's finding that program participation predicts changes in levels of adherence to traditional masculinity ideology over time. In addition to providing support for quantitative findings, the thematic analysis highlights some potential gaps in the quantitative assessment of masculinity ideology that must be considered in future research. For example, youth describe an alternative ideal form of masculinity, sometimes characterized by the youth as "man up," that provides a level of flexibility that is counter to that of traditional masculinity. Moreover, the qualitative findings also raise questions about the validity of the survey measure of masculinity (AMIRS; Chu, 2005) for use with African American and incarcerated youth. Finally, the study supports theories of multiple masculinities and offers preliminary evidence that gender specific, strengths-based programming can influence adherence to traditional masculinity ideology among youth in juvenile justice facilities.