Dr. Nandika Sanath Kumanayake joined the government service as an Assistant Superintendent of Sri Lanka Customs in 1997. He studied at Rahula College, Matara, and obtained his BSc degree with first-class honors from the University of Kelaniya.

After receiving a scholarship from the World Customs Organization (WCO), he pursued a Master of Public Finance at the National Graduate Institute for Policy Studies (GRIPS) in Tokyo, Japan. He was further awarded a university scholarship to complete an MA in Public Economics and a Ph.D. in Development Economics at the GRIPS-Japan. His research focused on the issue of customs corruption, and he has published several papers in international journals.

He is now accredited by the World Customs Organization as a Customs Modernization Advisor, specializing in Integrity Development. He has participated in several WCO international delegations to conduct programs in foreign countries aimed at enhancing the integrity of customs systems.