Since 2010, Costa Mariakis has been a member of the Board of Directors of the Association of Health-Research and Biotechnology Industry (SEIV) and for the last four years he has been the Treasurer of the Association.
He is a graduate pharmacist and has a career beyond 40 years in the field of diagnostic products. He was been the first in charge of Abbott Diagnostic Division in Greece in 1978 till 1985. After working in Bakakos SA and the National Drugs Distribution Company  SA as Diagnostic Manager, he founded the company New Diagnostic Dimension Ltd in 1992 and continues its management with an ascending course.
He speaks four languages ​​and is married.