This volume contains revised papers from the Rough Set and Knowledge Technology Conference (RSKT 2008), together with five papers introducing advances in rough set theory and its applications. It is part of the LNCS Transactions on Rough Sets series.

Granular Rough Mereological Logics with Applications to Dependencies in Information and Decision Systems.- On Topological Dominance-based Rough Set Approach.- A Study of Multiple-Source Approximation Systems.- A New Knowledge Reduction Algorithm Based on Decision Power in Rough Set.- Comparison of Some Classification Algorithms Based on Deterministic and Nondeterministic Decision Rules.- Gene Selection and Cancer Classification: A Rough Sets Based Approach.- Evolutionary-Rough Feature Selection for Face Recognition.- Spatial Reasoning Based on Rough Mereology: A Notion of a Robot Formation and Path Planning Problem for Formations of Mobile Autonomous Robots.- Perceptually Near Pawlak Partitions.- A Novel Split and Merge Technique for Hypertext Classification.- A Non-boolean Lattice Derived by Double Indiscernibility.- Rough Set Approximations in Formal Concept Analysis.- On the Relation between Jumping Emerging Patterns and Rough Set Theory with Application to Data Classification.