In their Policy Forum “Achieving STEM diversity: Fix the classrooms” (3 June, p. 1057), J. Handelsman et al. explain that past interventions have not resulted in equitable representation for students from historically excluded communities in science, technology, engineering, and mathematics (STEM). We agree that implementation of their suggested classroom changes would likely contribute to greater persistence and retention in STEM throughout college. However, fixing the classroom alone will not be sufficient. If we are to achieve a fully inclusive workforce (1, 2), we need a comprehensive approach that simultaneously and collaboratively addresses factors both within and outside the classroom (3).