Interventions to foster inclusive learning environments may benefit college STEMM instructors (NASEM, 2019). We investigated the impact of a social inclusion intervention (SII) on scientific self-efficacy, identity, community values, and persistence intentions in a large and diverse sample of biomedical college instructors (n = 116) in the USA. The results indicated that the SII group developed stronger scientific community values than the control group, and the effect was the strongest for instructors who had initially expressed lower values. From a mentoring perspective, the intervention helps boost feelings of community values, which is linked to increased persistence in STEMM careers.