Her teaching and research center on the history of women and American religion and the study of U.S. Catholicism. Her first book, New Women of the Old Faith: Gender and American Catholicism in the Progressive Era, was published in 2009 with the University of North Carolina Press. At present Cummings is working on a new book, Citizen Saints: Catholics and Canonization in American Culture. Cummings received an NEH Fellowship to support work on this project during the academic year 2010-11. Her most recent publication is "American Saints: Gender and the Re-Imaging of American Catholicism in the Early Twentieth Century," which appears in the summer 2012 issue of Religion and American Culture.