 Chang was Professor/Chairman of the Department of Biomedical Engineering at the University of Southern California (USC) from 1985 to 1990.He was a founding Dean of the School of Engineering at the Hong Kong University of Science and Technology in 1990, and the Dean of the School of Engineering of the University of Pittsburgh in 1994.He was appointed to be the President of the City University of Hong Kong in 1996; he retired in 2007.