Commercial tools are heavily used, relatively cheap, well maintained, and provide powerful functionalities. However, composing these tools in order to build larger applications raises a lot of difficulties not found in component based system. Our work seeks at building a platform that makes entities of various types (component, COTS, tools, etc.) interoperate in order to build a new application. We call this new kind of application a federation. Our federations use workflow as a support for applications integration and interoperability. In this approach, the process is not defined in term of tools and their parameters; instead, the process is high d describes only abstract steps without knowledge on how these steps will be carried out. Therefore, the federation offers a mean to describe rol the synchronization between the abstract and executable process, and a set of concrete tools. The federation ensures that the execution of the level involves a compatible real execution at the conc...