Consideration of socioemotional skills in admissions potentially can increase representation of racial and ethnic minorities and women in graduate and professional education as well as identify candidates more likely to succeed in graduate and professional school. Research on one such assessment, the ETS Personal Potential Index (PPI), showed that the PPI produced much smaller racial/ethnic-gender group mean score differences than undergraduate grade point average (UGPA) and the Graduate Record Examinations (GRE) did. Across levels of institutional selectivity, the PPI can promote racial/ethnic and gender diversity in graduate and professional school in ways that UGPA and GRE scores do not. Predictive validity analyses showed that for doctoral STEM programs the PPI dimensions of (1) Planning and Organization and (2) Communication Skills positively predict school grade point average as well as a lower risk of academic probation, a determinant of degree progress, both alone and incrementally over UGPA and GRE scores.