Business-to-business (B2B) data exchange and integration is a common daily operation in today’s organizations. These operations are crucial since they affect organizations’ capability to compete in today’s marketplace. Data exchange and integration has been proven to be a challenge due to the heterogeneity of the information systems involved."This paper described a Syntactic-to-Semantic (S2S) middleware which, when based on a single query, integrates data residing in different data sources possibly with different formats, structures, schema, and semantics. The middleware uses an ontology-based multi-source data extractor/wrapper approach to transform syntactic data into semantic knowledge.