This page lists classical pieces in the trombone repertoire, including solo works, concertenti and chamber music of which trombone plays a significant part.
Howard J. Buss, Odyssey for 4 Trombones (1987), Levi's Dream for 4 Trombones (2011), Brom Bones for 8 Trombones (2010), Showdown for 10 Trombones (1987), Prayer for 12 Trombones (2015), Trombone Graffiti for 4 Trombones (2016),