Fundamentals of Reasoning and Reasoning Languages.- Foundations of Rule-Based Query Answering.- Reasoning in Description Logics: Basics, Extensions, and Relatives.- Rules, Rule Languages, and Policies.- Reactive Rules on the Web.- Rule-Based Policy Representation and Reasoning for the Semantic Web.- Rule Interchange on the Web.- Applications of Semantic Web Reasoning.- Reasoning in Semantic Wikis.- Semantic Wiki Representations for Building an Enterprise Knowledge Base.- Semantic Descriptions in an Enterprise Search Solution.- Semantic Web Service Discovery and Selection in B2B Integration Scenarios.