Lesbian, gay, bisexual, transgender, queer, and other sexual and/or gender minority (LGBTQ+) populations experience significant mental and behavioral health disparities. Social workers are uniquely positioned to address these vulnerabilities. However, clinical graduate education has not effectively promoted or taught competent practice with LGBTQ+ populations. This qualitative study details the foundational competencies required for affirmative practice in group therapy with LGBTQ+ populations and describes a simulation-based learning activity designed to develop these competencies in graduate students. The following themes were identified as critical to affirmative practice, as identified through student reflections on their simulation-based learning experiences: deeply engaging in a strengths-based stance, keeping the group in group therapy, avoiding the expert trap, and managing identity assumptions. Implications for clinical social work education and practice are discussed.