|Born||Colombo, Sri Lanka|
|Alma mater||Royal College Colombo
University of Ceylon, Peradeniya
Educated at the Royal College, Colombo and graduated with a LLB degree in law from the University of Ceylon, Peradeniya. He was the brother of Professor K. N. Seneviratne, Professor of Medicine and founder director of Sri Lanka's Postgraduate Institute of Medicine.
Upon graduation he joined the office of the clerk of House of Representatives, and went on to become the Secretary General of Parliament. He was Secretary General and present at the parliament during the 1987 grenade attack in the Sri Lankan Parliament.