This paper presents a Web-based data integration methodology and tool framework, called X-TIME, for the development of Business-to-Business (B2B) design environments and applications. X-TIME provides a data model translator toolkit based on an extensible meta model and XML. It allows the creation of adaptable semantic-oriented meta models to support the design of wrappers or reconciliators (mediators), taking into account characteristics of interoperable information systems, such as extensibility and composability. X-TIME defines a set of meta types which correspond to g meta level semantic descriptors of data models found in the Web. The meta types are organized in a generalization hierarchy to capture semantic similarities among modeling concepts of interoperable systems. We show how to use the X-TIME methodology to build cooperative environments for B2B platforms involving the integration of Web data and services.