He received the Diploma in Electrical Engineering and the PhD degree in Computer Science from the Aristotle University of Thessaloniki, Greece, in 1996 and 2000, respectively. From 1997 to 1999, he was with Intracom, Greece, as a telecommunications software designer. Since 2007, he is also a member of the teaching staff of Hellenic Open University. His research interests include object-oriented design, software maintenance, and software evolution analysis. He has published more than 80 papers in international refereed journals and conferences while his research work has received more than 1000 citations. In 2010 he was ranked by the Journal of Systems and Software among the 15 top scholars in the field of Systems and Software Engineering.