His theological research and writing focuses on moral theology, Catholic social teaching, virtue ethics, impairment and disability, and the theology of Thomas Aquinas. Romero's published writing has appeared in journals like The Thomist, Nova et Vetera, the Journal of Moral Theology, and the Journal of Disability & Religion. He is on the Board of Directors for the National Catholic Partnership on Disability. Romero completed his doctoral studies and postdoctoral training, respectively, at Duke University and the University of Notre Dame.