He studied early music and recorder with Barthold Kuijken, Koen Dieltiens, Jos Van Immerseel and Balderick Deerenberg in Antwerp and jazz piano, composition and free improvisation with Dennis Luxion, Frederic Rzewsky, Garrett List and Philippe Boesmans in Liège. Defoort is a major figure in the European jazz scene. His music is characterised by the encounter between classic and jazz music, and between written compositions and improvisation.
After masterclasses in New York at the end of the 1980s, Defoort worked in Belgium as a composer, pianist and improviser and led various jazz ensembles. He wrote for dance and theatre, composed two operas, ‘The Woman Who Walked into Doors’ and ‘House of the Sleeping Beauties’ and wrote work for orchestras. Recently, he collaborated with baroque orchestra B'Rock en composed a circus opera. In 2018 a new opera premiered at La Monnaie, based on the novel ‘The Time of Our Singing’ by Richard Powers, directed by Ivo van Hove.