Rehding spent many years at the other Cambridge (BA, MA, MPhil, PhD) and held research fellowships at Emmanuel College Cambridge, the Penn Humanities Forum and the Princeton Society of Fellows before joining the Harvard Department in 2003, initially as Assistant Professor. Rehding was co-editor of Acta musicologica 2006-2011, and is Editor-in-chief of the Oxford Handbook Online series in Music (now Oxford Research Reviews).
As a music theorist, Rehding is interested in the question of how music has been understood at different times in history. This has taken his work in a number of different directions — from Ancient Greek music to the Eurovision Song Contest. He is interested in the history of music theory, paleo- and neo-Riemannian theory, music-aesthetic questions, and issues of sound and media.
Thanks to a generous grant from the Andrew W Mellon Foundation, he is the convener of the 2013/14 John E. Sawyer Seminar in the Comparative Study of Culture, Hearing Modernity.