More PhD programmes in science and engineering should adopt the mentoring model developed by Casey Miller and Keivan Stassun to boost numbers of female and minorities students (see Nature 510, 303–304; 2014). They should also use more-inclusive admissions criteria.

Efforts to democratize and diversify US higher education are placing a growing emphasis on applicants' social and economic origins (see, for example, W. G. Bowen et al. Equity and Excellence in American Higher Education Univ. Virginia Press, 2005). I suggest that admissions measures be expanded to include applicants who are first-generation college students, for example, or who were raised in poverty or in deprived single-parent families.

This broadened approach would fit with Miller and Stassun's recommendation that admissions practices be augmented with “proven markers of achievement, such as grit and diligence”.