Paul Douglas Hillier OBE (born 9 February 1949) is an English conductor, music director and baritone. He specializes in both early and contemporary classical music, especially that by composers Steve Reich and Arvo Pärt. He was a co-founder of the Hilliard Ensemble as well Theatre of Voices, and directed the Estonian Philharmonic Chamber Choir for many years. He has been Chief Conductor of Ars Nova (Copenhagen) (2003-2023), and Artistic Director and Chief Conductor of Chamber Choir Ireland (formerly known as the National Chamber Choir of Ireland) since 2008.