After university Kunaratnam worked at the University of Ceylon, Colombo and
University of Ceylon, Peradeniya. He remained head of the department until October 1980. He then served as Head of the Department of Physics from March 1994 and April 1994. He served as vice-chancellor of the university between April 1994 and February 1997. Kunaratnam retired in April 2000. Kunaratnam was elected fellow of the
Royal Astronomical Society in 1998 and fellow and chartered Physicist of the
Institute of Physics in 1999. Kunaratnam died on 9 September 2015 in
Colombo. ==References==