Constitutes the refereed proceedings of the First International Conference on Web Reasoning and Rule Systems, RR 2007, held in Innsbruck, Austria. This book addresses various topics in Web reasoning and rule systems, including acquisition of rules and ontologies by knowledge extraction, design and analysis of reasoning languages.

I FullPapers.- Well-Founded Semantics for Hybrid Rules.- Rule-Based Composite Event Queries: The Language XChangeEQ and Its Semantics.- On the Semantics of Service Compositions.- Expressive Reasoning with Horn Rules and Fuzzy Description Logics.- Quantified Equilibrium Logic and Hybrid Rules.- Web Services Discovery and Constraints Composition.- Ontological Reasoning to Configure Emotional Voice Synthesis.- A Semantic Framework for Language Layering in WSML.- Merging Model Driven Architecture and Semantic Web for Business Rules Generation.- A Framework for Combining Rules and Geo-ontologies.- Domain Ontology Learning and Consistency Checking Based on TSC Approach and Racer.- : An Integration of Description Logic and General Rules.- Evaluating Formalisms for Modular Ontologies in Distributed Information Systems.- Consistent Query Answering over Description Logic Ontologies.- II Short Papers.- A Context-Based Architecture for RDF Knowledge Bases: Approach, Implementation and Preliminary Results.- Towards a Hybrid System Using an Ontology Enriched by Rules for the Semantic Annotation of Brain MRI Images.- A Framework for Ontology Based Rule Acquisition from Web Documents.- A Fast Algebraic Web Verification Service.- Proof Explanation in the DR-DEVICE System.- Rule-Based Active Domain Brokering for the Semantic Web.- Decidability Under the Well-Founded Semantics.- A Rule-Based Approach for Reasoning About Collaboration Between Smart Web Services.- Tightly Integrated Fuzzy Description Logic Programs Under the Answer Set Semantics for the Semantic Web.- AceRules: Executing Rules in Controlled Natural Language.- Bridging Concrete and Abstract Syntax of Web Rule Languages.- Completing Queries: Rewriting of Incomplete Web Queries Under Schema Constraints.- Attaining Higher Quality for Density Based Algorithms.- Correlation Rules and Ontologies Acquisition in Knowledge Extraction of Image.- Hybrid Reasoning with Rules and Constraints under Well-Founded Semantics.- III Selected Posters.- Extending SWRL to Enhance Mathematical Support.- Efficiently Querying Relational Databases Using OWL and SWRL.- Top-Down Computation of the Semantics of Weighted Fuzzy Logic Programs.- A Visualization Algorithm for Defeasible Logic Rule Bases over RDF Data.- Efficient OWL Reasoning with Logic Programs – Evaluations.- Reasoning About XML Schema Mappings in the Presence of Key Constraints and Value Dependencies.- Context in Rules Used in P2P Semantic Data Integration System.