Extended Abstracts of Invited Lectures -- Philosophical Aspects of Computerized Verification of Mathematics -- A Science of Reasoning (Extended Abstract) -- Model Checking: Historical Perspective and Example (Extended Abstract) -- Comparison -- Comparison of Theorem Provers for Modal Logics — Introduction and Summary -- FaCT and DLP -- Prover KT4 -- leanK 2.0 -- Logics Workbench 1.0 -- Optimised Functional Translation and Resolution -- Benchmark Evaluation of ?KE -- Abstracts of the Tutorials -- Implementation of Propositional Temporal Logics Using BDDs -- Computer Programming as Mathematics in a Programming Language and Proof System CL -- Contributed Research Papers -- A Tableau Calculus for Multimodal Logics and Some (Un)Decidability Results -- Hyper Tableau — The Next Generation -- Fibring Semantic Tableaux -- A Tableau Calculus for Quantifier-Free Set Theoretic Formulae -- A Tableau Method for Interval Temporal Logic with Projection -- Bounded Model Search in Linear Temporal Logic and Its Application to Planning -- On Proof Complexity of Circumscription -- Tableaux for Finite-Valued Logics with Arbitrary Distribution Modalities -- Some Remarks on Completeness, Connection Graph Resolution, and Link Deletion -- Simplification and Backjumping in Modal Tableau -- Free Variable Tableaux for a Logic with Term Declarations -- Simplification A General Constraint Propagation Technique for Propositional and Modal Tableaux -- A Tableaux Calculus for Ambiguous Quantifiation -- From Kripke Models to Algebraic Counter-Valuations -- Deleting Redundancy in Proof Reconstruction -- A New One-Pass Tableau Calculus for PLTL -- Decision Procedures for Intuitionistic Propositional Logic by Program Extraction -- Contributed System Descriptions -- The FaCT System -- Implementation of Proof Search in the Imperative Programming Language Pizza -- p-SETHEO: Strategy Parallelism in Automated Theorem Proving.