Events in 2020, including the killings of George Floyd, Breonna Taylor, and others, ignited a global conversation across all sectors of society about racism, white supremacy, and other systems of oppression experienced by marginalized groups. The geoscience community has responded with statements, reading groups, and committees addressing the overall lack of diversity, equity, and inclusion within our field. The sad truth is that our community has discussed its lack of diversity, particularly related to race and gender, for decades with few measurable improvements (Bernard & Cooperdock, 2018; Bromery, 1972). This lack of diversity, which spans race, gender, disability, sexuality and other social categories, contributes directly to the lack of inclusion and equity experienced by people from marginalized groups (Dutt, 2020). Recent efforts have focused on systemic bias-the ways in which institutional culture, norms, and procedures exclude people based on their social identity and/or background, in both intentional and unintentional ways. Several calls have been made to address this at the institutional and federal agency level (e.g., notimeforsilence.org), and many professional societies responded by updating codes of conduct and retooling other functions with a diversity lens. At the same time, faculty, principal investigators (PIs), and other scientists that manage labs, lead fieldwork, or teach students also have an important role to play. As authoritative figures of environments that people navigate on a near-daily basis, these individuals have outsized influence over the spaces where students and trainees most keenly feel the adverse impacts of systemic bias. This power to alter career trajectories is most apparent with reference letters, grades, and providing access to resources and opportunities ("gatekeeping"), but it also manifests subtly in day-today interactions and norms that can either support or undermine people's sense of belonging, fulfillment, and confidence. Here, we highlight actions for scientists supervising labs, fieldwork, and classrooms to address systemic biases that impact students and trainees, our next generation of geoscientists. While faculty and PIs are the target of this article, these ideas are relevant to any individual in a position of authority (e.g., lab managers, teaching assistants, fieldwork organizers). We focus on tractable actions that can have immediate positive impacts for marginalized community members, mitigating harm while critical but protracted progress continues at higher organizational levels (Keisling et al., 2020; Ovienmhada et al., 2020). We call on all scientists in leadership roles to personally reflect and engage with research on anti-oppressive practices published by historians, social scientists, and education scholars, and to translate this learning into sustained, lifelong action.