Timos Sellis received his diploma degree in Electrical Engineering in 1982 from the National Technical University of Athens (NTUA), Greece. In 1983 he received the M.Sc. degree from Harvard University and in 1986 the Ph.D. degree from the University of California at Berkeley, both in Computer Science. In 1986, he joined the Department of Computer Science of the University of Maryland, College Park as an Assistant Professor, and became an Associate Professor in 1992. Between 1992 and 1996 he was an Associate Professor at NTUA, where he served as a Professor till January 2013. He is currently a Professor at the School of Computer Science and Information Technology of RMIT University in Australia. Timos was also the Director of a new research institute he founded in Greece, the Institute for the Management of Information Systems (IMIS) of the "Athena" Research Center (www.imis.athena-innovation.gr) between 2007 and 2012. His research interests include data streams, peer-to-peer database systems, personalization, the integration of Web and databases, and spatio- temporal database systems. He has published over 200 articles in refereed journals and international conferences in the above areas and has been invited speaker in major international events. He has also participated and co-ordinated several national and european research projects. Prof. Sellis is a recipient of the prestigious Presidential Young Investigator (PYI) award given by the President of USA to the most talented new researchers (1990), and of the VLDB 1997 10 Year Paper Award in 1997 (awarded to the paper published in the proceedings of the VLDB 1987 conference that had the biggest impact in the field of database systems in the decade 1987-97). He was the president of the National Council for Research and Technology of Greece (2001-2003), and in November 2009, he was awarded the status of IEEE Fellow, for his contributions to database query optimization, and spatial data management.