This special issue of the Information-Interaction-Intelligence (I3) Journal presents a collection of papers on the topic of ”Complex Object Matching and Discovery”. Applications such as digital libraries, mediation systems and web services-based architectures produce masses of data and describe complex objects such as documents, business processes, services and onto¬logies for different knowledge domains. They are therefore heterogeneous and rich in terms of semantics. Giving the richness of these models and the huge number of stored objects, new techniques and tools are required to help user to retrieve the object satisfying his needs and preferences. This special issue highlights and explores some of the more recent theoretical and practi¬cal advances in complex object matching and discovery.We received 9 submissions from France, China, Tunisia, Brazil from which 4 papers were accepted. The four selected papers deal with matching and of web services, complex image objects, XML documents and ontology align¬ment.REVIEWERSFabio Casati (University of Trento, Italy)Daniela Grigori (PRiSM, University of Versailles St-Quentin en Yvelines, France)Mohand-Saïd Hacid (LIRIS, University of Lyon 1, France)Hamamache Kheddouci (LIESP, University of Lyon 1, France)Geetika T. Lakshmanan (IBM T. J. Watson Research Center, Hawthorne, NY)Ludovic Lietard (IRISA, University of Rennes 1, France)Stéphane Lopes (PRiSM, University of Versailles St-Quentin en Yvelines , France)Hamid Reza Motahari Nezhad, (Hewlett Packard Laboratories, Palo Alto, California)Amedeo Napoli (LORIA, Nancy, France)Andreas Nürnberger (University of Magdeburg, Germany)Olivier Perrin (LORIA, Université Nancy 2, France)Karen Pinel-Sauvagnat, (IRIT, University Paul Sabatier, Toulouse, France)Editorial Daniela Grigori, Ludovic LietardA Semantic Framework for Web service Annotation, Matching and Classification in Bioinformatics Nadia Yacoubi Ayadi, Malika Charrad, Maria-Esther Vidal, Mohamed Ben Ahmed, Soumaya Amdouni An Infrastructure for Searching and Harvesting Complex Image ObjectsNadia P. Kozievitch, Ricardo da S. Torres, André Santanchè, Daniel C. G. Pedronette, Rodrigo T. Calumby, Edward A. FoxA semantic approach for discovering complex alignmentsMyriam Lamolle, Chan Le Duc, Rim TouhamiTwigStack++ : A New Efficient Holistic Twig Join AlgorithmMohammed Amin Tahraoui and Hamamache Kheddouci
