This volume of the Transactions on Rough Sets commemorates the life and work of Zdzislaw Pawlak (1926-2006), whose legacy is rich and varied. It presents papers that reflect the profound influence of a number of research initiatives by Professor Pawlak, introducing a number of new advances in the foundations and applications of artificial intelligence, engineering, logic, mathematics, and science.

Contributed Papers.- Propositional Logics from Rough Set Theory.- Intuitionistic Rough Sets for Database Applications.- An Experimental Comparison of Three Rough Set Approaches to Missing Attribute Values.- Pawlak's Landscaping with Rough Sets.- A Comparison of Pawlak's and Skowron-Stepaniuk's Approximation of Concepts.- Data Preparation for Data Mining in Medical Data Sets.- A Wistech Paradigm for Intelligent Systems.- The Domain of Acoustics Seen from the Rough Sets Perspective.- Rule Evaluations, Attributes, and Rough Sets: Extension and a Case Study.- The Impact of Rough Set Research in China: In Commemoration of Professor Zdzis?aw Pawlak.- A Four-Valued Logic for Rough Set-Like Approximate Reasoning.- On Representation and Analysis of Crisp and Fuzzy Information Systems.- On Partial Covers, Reducts and Decision Rules with Weights.- A Personal View on AI, Rough Set Theory and Professor Pawlak.- Formal Topology and Information Systems.- On Conjugate Information Systems: A Proposition on How to Learn Concepts in Humane Sciences by Means of Rough Set Theory.- Discovering Association Rules in Incomplete Transactional Databases.- On Combined Classifiers, Rule Induction and Rough Sets.- Approximation Spaces in Multi Relational Knowledge Discovery.- Finding Relevant Attributes in High Dimensional Data: A Distributed Computing Hybrid Data Mining Strategy.- A Model PM for Preprocessing and Data Mining Proper Process.- Monographs.- Lattice Theory for Rough Sets.