  In this paper, we present a method and a tool for deriving a skeleton of an
ontology from XML schema files. We first recall what an is ontology and its
relationships with XML schemas. Next, we focus on ontology building methodology
and associated tool requirements. Then, we introduce Janus, a tool for building
an ontology from various XML schemas in a given domain. We summarize the main
features of Janus and illustrate its functionalities through a simple example.
Finally, we compare our approach to other existing ontology building tools.
