Hilary Jeffery, born 1971 in Surbiton, United Kingdom, is a British improvisational musician known for his work in trombone, electronics, and compositions. After studying at Dartington College of Arts, the University of York, the Institute of Sonology, and with James Fulkerson at the European Dance Development Centre in Arnhem, he began collaborating with choreographers such as Aurora Corsano and Vania Gala. Jeffery released solo projects such as Solo Trombone & Electronics (2003) and Solo Trombone & Electronics 2 (2006) on FMR Records. He later joined the ensemble Zeitkratzer. He also worked with Robin Hayward and Elena Margarita Kakaliagou in Zinc & Copper, which led to a 2017 performance at Berlin Jazz Festival.
