Canadian composer, saxophonist and sound collage artist, best known for his plunderphonics, which involves using samples of existing recordings to create a new work. Examples include the Grayfolded releases, a plunderphonics-like treatment of recordings of the Grateful Dead's Dark Star. His improvisational work includes leading an (improvising) orchestra weekly for most of the 1980s and performing as an alto saxophonist in a variety of lineups as well as solo. He has composed numerous scores for dance and has conducted an improvised dance workshop for over a decade.

Oswald is the research director for Toronto's Mystery Laboratory experimental studio, and NorthAmerican Experience's music director. He has produced a number of recordings, and has his own releases on the Swell and Musicworks labels, among others.