Following changes in business processes and technology enterprises often need to interoperate protocols of heterogeneous middleware. This paper presents an automated, data-driven approach to protocol-level middleware interoperation, based on declarative descriptions of these protocols. The run-time engine of TUBE (The Ubiquitous Broker Environment), provides a layer between application-level components and middleware that allows a degree of independence from particular middleware implementations by taking protocol descriptions and performing the necessary translations. The TUBE framework is designed to try alternatives if the searched protocol is unavailable, making it easy to deploy different types of middleware and special protocol extensions.  TUBE has been implemented and successfully tested across a range of commonly used middleware, including synchronous, asynchronous, object-based, binary and text-based protocols. Key components of the system are currently in operation in a large Australian corporation.