This chapter outlines the genesis, scope, and methods of the Gender Matters research into the current policy and practice gap in secondary schools around gender and gender-based issues. It articulates our key concepts, including how we understand gender and gender justice and the parameters and implications of other terminology. We situate our research within historical trajectories of gender-equity policies in education, highlighting a contemporary sociopolitical climate marked by increased misogyny, transphobia, sexual violence, and conservative interventions targeting gender-inclusive practices in schools. The chapter introduces our participants—recent school leavers, current school students, teachers, and school leaders—in two Australian jurisdictions with divergent policy approaches to gender issues in education. Through qualitative methods entailing interviews, focus groups, and innovative arts-based methodologies such as affective filmmaking, our research captured complex, affective, and nuanced dimensions of gendered experiences. This chapter introduces our central argument that new forms of gender oppression have emerged, particularly affecting trans and non-binary identities, while long-standing forms of exclusion and oppression persist due to stereotypical assumptions about gender that detrimentally impact young people’s futures. Emphasising the transformative potential of gender justice—an activist-oriented, inclusive approach—we argue for the urgent need for systemic policy interventions that amplify student and teacher voices, critically address contemporary challenges, and foster equitable, inclusive educational environments.