%K oeg %X Ontology-based applications play an increasingly important role in the public and corporate Semantic Web. While today there exist a range of tools and technologies to support specific ontology engineering and management activities, architectural design guidelines for building ontology-based applications are missing. In this paper, we present an architecture for ontology-based applications—covering the complete ontology-lifecycle—that is intended to support software engineers in designing and developing ontology based-applications. We illustrate the use of the architecture in a concrete case study using the NeOn toolkit as one implementation of the architecture. %L upm4923 %B Proceedings of the ISWC 2007 + ASWC 2007. The 6th International Semantic Web Conference and the 2nd Asian Semantic Web Conference 2007 %C Busan, South Korea %A T. Tran %A Peter Haase %A Holger Lewen %A O. Muñoz-García %A A. Gómez-Pérez %A R. Studer %O Ontology Engineering Group – OEG %D 2007 %I Informatica %T Lifecycle-Support in Architectures for Ontology-Based Information Systems