Prof Samaranayake played a major role in the development of IT and IT related education in Sri Lanka.

He was at the time of his death the chairman of the Information and Communication Technology Agency (ICTA) of Sri Lanka and was the founding and former director of the University of Colombo School of Computing (UCSC).

Samaranayake served the Council for Information Technology (CINTEC), the apex National agency for IT in Sri Lanka as its chairman for a period of 12 years.

In the field of IT he has pioneered work on IT Policy, Legal Infrastructure, EDI/E-Commerce, Security, Internet Technology, Computer Awareness and IT Education.

Samaranayake was actively involved in the formulation of the WASO 10646 standard for Sinhalese Characters and in the development of multilingual web sites and has been instrumental in helping to apply computers in many areas of governance, including in national elections.

More recently he initiated the External Degree of Bachelor of Information Technology (BIT) of the University of Colombo, which in its very first year of operation has attracted 5000 registrations.