Wojciech Ziarko received the M.Sc. degree in Applied Mathematics from the Faculty of Fundamental Problems of Technology of the Warsaw University of Technology, Warsaw, Poland, in 1975. In 1980, he received the Ph.D. degree in Computer Science specializing in databases from the Institute of Computer Science of Polish Academy of Sciences, Warsaw, Poland. His supervisor in both M.Sc. and Ph.D. theses was Professor Zdzis?aw Pawlak. In 1982, he joined the University of Regina, Canada where he is now a Professor in the Computer Science Department. He is also a co-director of the Rough Set Research Technology Laboratory at the University of Regina. His research interests are rough sets, knowledge discovery in databases, machine learning, pattern classification and control algorithm acquisition from data. The theory of rough sets, in particular its probabilistic extensions, serve as a basic mathematical framework in much of his research work. His best known contribution is the variable precision model of rough sets, which is the basis of many real-life applications of rough sets. He authored or co-authored over one hundred and forty papers and edited or co-edited three books on the above subjects. He also taught several graduate-level classes on rough sets and applications. He is currently involved in the development of applications of his research in data mining, pattern classification and control applications. He organized the International Workshop on Rough Sets and Knowledge Discovery (Banff, Canada, 1993), chaired the International Workshop on Rough Sets and Soft Computing (San Jose, 1994), co-chaired the International Workshop on Rough Sets, Fuzzy Sets and Knowledge Discovery (Tokyo, Japan, 1996), co-organized and chaired the International Conference on Rough Sets and Current Trends in Computing (Banff, Canada, 2000) and co-organized and co-chaired the International Conference on Rough Sets, Fuzzy Sets, Data Mining, and Granular Computing (Regina, Canada 2005).