He teaches across the range of art history, and his scholarly specialization is Byzantine and medieval art, with a focus on how such images inform contemporary visual culture. Dr. Milliner has published widely in both academic and popular venues, and has given scholarly presentations at University of Chicago, American University, Indiana University, and Duke University. In 2014 he organized a scholarly symposium at the Art Institute of Chicago entitled Envisioning the Eucharist, which explored how art functions as visual theology. He is a National Humanities Center Summer Institute for Advanced Study Fellow for 2013 and 2014, and serves as a member of the Curatorial Advisory Board of the United States Senate.