Int. J. of Information Technology and Web Engineering, 2(4), 21-40, October-December 2007 21 Copyright © 2007, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. ABSTrACT The Web services paradigm has enabled an increasing number of providers to host remotely accessible services. However, the true potential of such a distributed infrastructure can only be reached when such autonomic services can be combined together as parts of a workfow, in order to collectively achieve combined functionality. In this article, we present our work in the area of automatic workfow composition among Web services with semantically described functionality capabilities. For this purpose, we use a set of heuristics derived from the connectivity structure of the service repository in order to effectively guide the composition process. The methodologies presented in this article have been inspired by research in areas such as graph network analysis, social network analysis, and bibliometrics. In addition, we present comparative experimentation results in order to evaluate the presented techniques. Keywords: heuristics; information network; semantic data model; semantic matching; Web applications; Web technologies Employing Graph Network Analysis for Web Service Composition John Gekas, University of Essex, UK Maria Fasli, University of Essex, UK INTrODUCTION The increasing popularity the Web Service paradigm and the Semantic Web have gained recently shows clearly the overall need for unifed access to semantically meaningful Web-based resources, whether these resources are data sources (such as Web sites) or functionality providers (in the form of Web applications and Web services). Numerous and valuable efforts have been presented in these research areas, coming both from industrial and academic colleagues. Furthermore, the notion of Service-Oriented Architecture (SOA) has arisen, referring to any decentralised software platform that allows the develop- ment, deployment, and integrated access to Web service applications. It has also been strongly argued that the full potential of such a service-oriented infrastructure can IGI PUBLISHING This paper appears in the publication, International Journal of Information Technology and Web Engineering , Volume 2, Issue 4 edited by Ghazi I. Alkhatib © 2007, IGI Global 701 E. Chocolate Avenue, Suite 200, Hershey PA 17033-1240, USA Tel: 717/533-8845; Fax 717/533-8661; URL-http://www.igi-pub.com ITJ3926