This volume contains the tutorial papers of the Summer School "Reasoning Web," July 25–29, 2005 (http://reasoningweb.org). The School was hosted by the University of Malta and was organized by the Network of Excellence REWERSE "Reasoning on the Web with Rules and Semantics" (http://rewerse.net), funded by the EU Commission and by the Swiss Federal Office for Education and Science within the 6th Framework Programme under the project reference number 506779. The objective of the school was to provide an introduction into methods and issues of the Semantic Web, a major endeavor in current Web research, where the World Wide Web Consortium W3C plays an important role.