Ontologies are consensual representations of a domain of discourse and the backbone of the future Semantic Web. Currently, however, only a fraction of Web users can take part in the process of building ontologies. In this paper, we show that standard Wiki technology can be easily used as an ontology development environment, reducing entry barriers for the participation of users in the creation and maintenance of ontologies, and describe our first OntoWiki prototype. Categories and Subject Descriptors H.5.3 [Information Interfaces and Presentation]: Group and Organization Interfaces – collaborative computing, computersupported cooperative work, Web-based interaction; I.2.4 [Artificial Intelligence]: Knowledge Representation Formalisms and Methods – Representation languages, Representations, Semantic networks; E.2 [Data]: Data Storage Representations. General Terms Management, Documentation, Human Factors, Languages Keywords Ontologies, Wiki, Semantic Web, Community-driven Ontology ...