 Currently (since 1987) he is Professor for violin and chamber music at the "" (ZHdK) known as Zurich University of the Arts in Switzerland where he also leads the ZHdK Strings chamber orchestra.He is frequently invited as a jury member at international violin competitions and gives masterclasses all around Europe, Asia and Australia.Koelman plays a violin made by Giovanni Francesco Pressenda in 1829 and the "Woolhouse" Stradivarius made in 1720.