Stefanos was born in 1962 in Athens. He went to high school in the Hellenic American Educational Foundation (Athens College) and subsequently studied Civil Engineering in the National Technical University of Athens on a state scholarship. After his graduation, he continued his education in Yale University (1986-1988), where he obtained a Master’s in Business Administration.
During 1988-1990, he worked for Citicorp in New York and Athens, participating in the planning and financing of energy projects in the Middle East.
During 1991-2007, he was active in the public works sector as a shareholder and CEO of a construction company, specialized in state buildings, as well as in infrastructure and energy projects.
Since 2000, he has also acted as a shareholder and CEO of a real estate development company, constructing several housing and office buildings, primarily in the Athens metropolitan area.
During 2019-2022, he served as the General Director of the Hellenic Cadastre.