Former President of the Sri Lanka Institute of Marketing (SLIM) he holds a Post Graduate Diploma in marketing from Chartered Institute of Marketing of UK. He is also a fellow of the same and Honoured by SLIM as a Practicing Marketer.

Mr. Seneviratne was the Director/Chief Executive Officer Mackwoods Healthcare (Pvt) Ltd. (From November 2006), a company dealing with Pharmaceuticals imported from leading manufacturers and retired in Dec 09.

He also held various positions in Marketing including that of Director sales& Marketing and Director Corporate Affairs & Medical Marketing at GlaxoSmithKline. For a short period, he functioned as Acting Chairman & Managing Director. During the 27 year period at GSK, he participated in numerous training programmes in several countries in the fields of Marketing, Sales, Leadership and Management.

Before the tenure at GSK, worked at Ceylon Tobacco Co, Suzuki Engineering Works and Hulugalle Samarasinghe & Co In the field of Accounting

Currently he is the Executive Marketing Consultant to ID Lanka Ltd.